ALBERT

Beschreibung:    We studied the effects of climatic factors on tree-ring width and vessel lumen area (VLA) in earlywood of English oak ( Quercus robur L.) in Latvia. Cores were obtained from healthy canopy oaks in 40 stands located across Latvia. Tree-ring widths and VLA were measured. Principal component analysis was used to arrange the sites along gradients of response of tree-ring width and earlywood to environmental factors. Significant relationships of tree-ring width and mean VLA with climatic factors (mean monthly temperature and precipitation sum) were determined by correlation analysis. Relationships between tree-ring, early- and latewood widths were tested in three sampled stands. The patterns of response of VLA and tree-ring width to environmental factors differed in relation to a west–east gradient of increasing continentality. Three regions of Latvia (western, central and eastern) were distinguished along this gradient. Responses to climate differed between tree-ring width and mean VLA. Occurrence of significant correlations between climatic factors and the proxies differed between regions, likely due to regional differences in temperature and precipitation. Tree-ring width correlated with climatic factors (most commonly with March, May and June temperature and August precipitation of the current growing season and July–August temperatures of the previous growing season); VLA was more strongly related to climatic factors, particularly with temperature in winter and spring months. The proportion of significant correlation coefficients with climatic factors differed between the regions. Among sites, significant correlation of tree-ring width with temperature in spring and summer was more frequent in the western region, while correlation with winter temperature of the previous growing season and precipitation in August was more frequent in the eastern region. For VLA, the frequency of significant correlation coefficients with temperature in winter and spring was higher in the eastern region. Content Type Journal Article Category Original Paper Pages 1-16 DOI 10.1007/s00468-012-0701-z Authors Roberts Matisons, Faculty of Biology, University of Latvia, Kronvalda bulv.4, Riga, LV-1010 Latvia Guntis Brūmelis, Faculty of Biology, University of Latvia, Kronvalda bulv.4, Riga, LV-1010 Latvia Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    Stem CO 2 efflux ( E S ) is an important component of forest ecosystem carbon budgets and net ecosystem CO 2 exchange, but little is known about E S in temperate forests in Northeastern China, an area with a large extent of forest. We measured E S along with stem temperature at 1 cm depth ( T s) over a 9 month period in 2007 on ten dominant tree species of secondary forests of the region. Other measurements included the autotrophic component of soil CO 2 efflux ( E A ) and stem diameter at breast height (DBH). Our objectives were to (1) examine the seasonal patterns and species differences in E S , and (2) determine the correlations between E S and T s, DBH and E A . Mean E S for the measurement period ranged from 1.09 to 1.74 μmol CO 2  m −2  s −1 among the ten species. The sensitivity of E S to T s ( Q 10 ) ranged from 1.87 to 2.61. Across the ten species 57–89% of variation in E S was explained by T S and DBH. There was also a linear relationship between mean E S and E A . E S was better predicted by T s in the dormant season than the growing season, indicating that additional factors such as growth respiration and internal transport of CO 2 in the xylem became more important contributors to E S during the growing season. Stem CO 2 efflux increased, and Q 10 decreased, with increasing DBH in all species. Although temperature exerts strong control on the rate of cellular respiration, we conclude that in tree stems in situ, T S , DBH and many other factors affect the relationship between CO 2 evolution by respiring cells and the diffusion of CO 2 to the stem surface. Content Type Journal Article Category Original Paper Pages 1-11 DOI 10.1007/s00468-012-0698-3 Authors J. Y. Yang, Center for Ecological Research, Northeast Forestry University, Harbin, 150040 China R. O. Teskey, Warnell School of Forestry and Natural Resources, University of Georgia, Athens, 30602 USA C. K. Wang, Center for Ecological Research, Northeast Forestry University, Harbin, 150040 China Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung: Context    Soluble organic nitrogen is considered to reflect the effect of forest types on soil nitrogen status. As a major process affecting the soil-soluble organic nitrogen pool, degradation of insoluble organic nitrogen in the production of soluble organic nitrogen is mediated by a suite of soil enzymes. Aims    This study aims to examine soil-soluble organic nitrogen pools and their relationships with the activities of soil enzymes in natural secondary forest stands and adjacent larch plantation stands. Methods    Four pairs of larch plantation stands and secondary forest stands were randomly selected from a mountainous area, and the top 15 cm of the mineral soils were sampled from each field. Results    The soil-soluble organic nitrogen concentrations were up to 2-fold greater in the secondary forest stands than in the larch plantation stands, whereas the ratio of soluble organic nitrogen/total nitrogen was comparable between the two forest types. The concentrations of soluble organic nitrogen were positively correlated with approximately 2-fold differences in urease and protease activities, a 1.2-fold difference in N -acetyl-β-glucosaminidase and a 1.7-fold difference in l -asparaginase between the two forest types. Conclusions    Our results suggest that relationships between soil-soluble organic nitrogen and enzyme activities are independent on sampling time, and that the soil enzyme activities can be used as potential indicators of soil soluble organic nitrogen pools in the temperate forest ecosystem. Content Type Journal Article Category Original Paper Pages 1-9 DOI 10.1007/s13595-012-0198-z Authors Kai Yang, Qingyuan Experimental Station of Forest Ecology, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, 110016 People’s Republic of China Jiaojun Zhu, Qingyuan Experimental Station of Forest Ecology, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, 110016 People’s Republic of China Qiaoling Yan, Qingyuan Experimental Station of Forest Ecology, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, 110016 People’s Republic of China Jinxin Zhang, Qingyuan Experimental Station of Forest Ecology, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, 110016 People’s Republic of China Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560

Beschreibung: Context   The scaling-up approach (which requires the use of individual tree biomass equations and data) is one of the most commonly used methods for estimating stand biomass at a local scale. However, biomass prediction over large management areas requires more efficient methods. Aims   Two methods of estimating aboveground stand biomass were developed and compared: stand biomass equations (SBE) including observed stand variables, and SBE including biomass expansion factors (BEF) and stand volume. Methods   Two types of systems of additive equations were fitted simultaneously for components and total aboveground stand biomass, to ensure additivity. Inherent correlations among biomass components were also taken into account in the fitting process. Results   The systems explained a high percentage of the observed variability. The SBE systems that included observed stand variables provided more accurate estimates than those that included BEF and stand volume. However, the latter were found to be more precise for stem wood and total aboveground biomass prediction. Conclusions   Both approaches provide a direct link between forest inventory data, outputs from whole-stand growth models, and biomass estimates at stand level. Taking into account that the inventory effort is similar for both alternatives, the choice of which to use will depend on the data available and on the relative importance of the biomass components for the end-users. Content Type Journal Article Category Original Paper Pages 1-12 DOI 10.1007/s13595-012-0191-6 Authors Fernando Castedo-Dorado, Departamento de Ingeniería y Ciencias Agrarias, Universidad de León. Escuela Superior y Técnica de Ingeniería Agraria, Avda. de Astorga s/n, 24400 Ponferrada, León, Spain Esteban Gómez-García, Departamento de Ingeniería Agroforestal, Universidad de Santiago de Compostela. Escuela Politécnica Superior, R/ Benigno Ledo, Campus Universitario, 27002 Lugo, Spain Ulises Diéguez-Aranda, Departamento de Ingeniería Agroforestal, Universidad de Santiago de Compostela. Escuela Politécnica Superior, R/ Benigno Ledo, Campus Universitario, 27002 Lugo, Spain Marcos Barrio-Anta, Departamento de Biología de Organismos y Sistemas, Universidad de Oviedo. Escuela Politécnica de Mieres, C/Gonzalo Gutiérrez Quirós, 33600 Mieres, Asturias, Spain Felipe Crecente-Campo, Departamento de Ingeniería Agroforestal, Universidad de Santiago de Compostela. Escuela Politécnica Superior, R/ Benigno Ledo, Campus Universitario, 27002 Lugo, Spain Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560

Beschreibung: • Context    There is little information about inter- and intra-specific variation in fuelwood properties of trees/shrubs in West Africa. • Aims    We studied variation in fuelwood properties of Balanites aegyptiaca , Combretum glutinosum , Guiera senegalensis , Piliostigma reticulatum , and Zizyphus mauritiana in the Sahelian and Sudanian ecozones of Mali. • Methods    Trees were sampled on different soil (sandy, sandy/loam, or rocky), land use (parkland agroforest or woodland), and terrain (flat, temporarily flooded, or hill slope) types in five regions extending from the drier eastern to the more humid western parts of Mali. Basic density, volatile matter, fixed carbon, ash content, moisture content, gross calorific value, and fuel value index were measured for each tree and adjusted for tree age. • Results    All fuelwood properties differed significantly among species, but there were significant species by region interactions. Most fuelwood properties of four species differed significantly among regions. Soil and/or land use type had significant effects on a few fuelwood properties of four species. • Conclusion    In general, fuelwood production is recommended in all regions for G. senegalensis , in drier regions for B. aegyptiaca and C. glutinosum , in more humid regions for Z. mauritiana , and on rocky soils for all species. Fuelwood production of P. reticulatum is not recommended. Content Type Journal Article Category Original Paper Pages 1-10 DOI 10.1007/s13595-012-0195-2 Authors Carmen Sotelo Montes, World Agroforestry Centre (ICRAF), Sahel Office, B. P. E 5118 Bamako, Mali John C. Weber, World Agroforestry Centre (ICRAF), Sahel Office, B. P. E 5118 Bamako, Mali Dimas A. Silva, Universidade Federal do Paraná, Av. Lothário Meissner, 900, CEP: 80270-170 Curitiba, Brazil Clarice Andrade, Universidade Federal do Paraná, Av. Lothário Meissner, 900, CEP: 80270-170 Curitiba, Brazil Graciela I. B. Muñiz, Universidade Federal do Paraná, Av. Lothário Meissner, 900, CEP: 80270-170 Curitiba, Brazil Rosilei A. Garcia, Instituto de Florestas, Departamento de Produtos Florestais, Universidade Federal Rural do Rio de Janeiro, BR 465, km 07, 23890-000, Seropédica, Rio de Janeiro, Brazil Antoine Kalinganire, World Agroforestry Centre (ICRAF), Sahel Office, B. P. E 5118 Bamako, Mali Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560

Beschreibung:    We analyzed the leaf phenology of European beech ( Fagus sylvatica ) and its variation due to spatial and temporal climatic variability, using a modified data set of the phenological network in Slovenia. We used first leaf unfolding (LU) and general leaf colouring (LC) time series of 47 sites (altitudes from 55 to 1,050 m a.s.l.) and corresponding climate series (52 of precipitation and 38 of temperature) for the period 1955–2007, collected by the Environmental Agency of the Republic of Slovenia. Across the network in average, LU occurred from 14 April until 13 May, and LC from 3 October until 29 October. LU was delayed by 2.6 days and LC was promoted by 1.9 days when the altitude increased by 100 m. Year-to-year variation of LU was significantly correlated with March and April temperatures. March temperatures had a greater effect at lower elevations and April ones at higher elevations. LC was related to August and September temperatures, and occurred later if the temperatures were higher. Recently, March and April temperatures showed an increasing trend and LU occurred 1.52 days earlier per decade at 1,000 m a.s.l. but no significant shifts were observed at lower altitudes. August temperatures were also increasing but the trends of LC were not significant and were not clearly related to altitude. Our detailed sub-regional data from a relatively small area with high geographic variability showed that changes in climate affect phenological response, mainly leaf unfolding, to a greater degree at higher altitudes than at lower ones. Content Type Journal Article Category Original Paper Pages 1-10 DOI 10.1007/s00468-012-0686-7 Authors Katarina Čufar, Department of Wood Science and Technology, Biotechnical Faculty, University of Ljubljana, Rožna Dolina, Cesta VIII/34, 1000 Ljubljana, Slovenia Martin De Luis, Department of Geography, University of Zaragoza, y O.T. C/Pedro Cerbuna 12, 50009 Zaragoza, Spain Miguel Angel Saz, Department of Geography, University of Zaragoza, y O.T. C/Pedro Cerbuna 12, 50009 Zaragoza, Spain Zalika Črepinšek, Agronomy Department, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000 Ljubljana, Slovenia Lučka Kajfež-Bogataj, Agronomy Department, Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, 1000 Ljubljana, Slovenia Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    Tsuga canadensis is often considered a foundation species because of its influence on the biological and ecological processes of upland forest systems. With hemlock woolly adelgid ( Adelges tsugae ; HWA)-induced mortality of T. canadensis in southern Appalachian upland forests, there is a crucial need to understand the regeneration dynamics of this tree species. This research was conducted within mature T. canadensis forests of Great Smoky Mountains National Park (GSMNP) prior to widespread HWA infestation. Tsuga canadensis regeneration abundance is lower than has been reported in more northern locales, but varies widely among sites in the southern Appalachian Mountains. Ordination results suggest landscape-scale patterns of regeneration abundance that are influenced by gradients in understory Rhododendron maximum cover, soil sand and nutrient content. Regression models reinforce the observed gradients in regeneration abundance. Sites with abundant T. canadensis regeneration have less R. maximum cover, soil sand and litter depth, but more soil nutrient availability. Tsuga canadensis seedlings and saplings tend to be spatially aggregated at the 14 × 21 m plot scale. Sites with spatially aggregated seedlings and saplings have greater canopy openness and more species with gap affinity. This research elucidates associations between successful T. canadensis regeneration and site factors such as soil nutrient availability and canopy dynamics. More forest surveys are required to understand the conditions necessary for successful T. canadensis regeneration. Land managers involved in forest restoration efforts may have to utilize appropriate silvicultural techniques conjoined with R. maximum removal operations to regenerate T. canadensis in southern Appalachian upland forests. Content Type Journal Article Category Original Paper Pages 1-12 DOI 10.1007/s00468-012-0681-z Authors Joshua A. Kincaid, Environmental Studies Department, Shenandoah University, 1460 University Drive, Winchester, VA 22601, USA Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    To contribute to a deeper understanding of interspecific relations between wood and tree size variables, 23 angiosperm tree species in two East African rain forests were investigated. The tree size variables were maximum tree height, maximum diameter, and maximum crown area. Wood was analyzed in regard of the physical variables specific gravity, water and gas fraction as well as the chemical variables carbon content and nitrogen content. All three tree size variables showed a significantly positive relation to each other. The wood physical variables showed negative correlations between the gas fraction and both specific gravity and the water fraction. Also positive relations were found between the water fraction and nitrogen content and between wood specific gravity and carbon content. Between tree size and wood physical variables, the gas fraction showed positive relations to both maximum tree height and diameter, while wood specific gravity was negatively related to maximum tree height and diameter. No significant correlations were found between the wood physical variables and the maximum crown area. Relationships among tree size variables can be explained by static constraints, while relations between the wood physical variables can be explained by a trade-off underlying structure and survival to support the species specific life strategy and tree architecture. Content Type Journal Article Category Original Paper Pages 1-12 DOI 10.1007/s00468-012-0687-6 Authors Gabriel Sebastian Becker, Institute of Botany, University of Hohenheim, Garbenstrasse 30, 70599 Stuttgart, Germany Désirée Braun, Institute of Botany, University of Hohenheim, Garbenstrasse 30, 70599 Stuttgart, Germany Robert Gliniars, Institute of Botany, University of Hohenheim, Garbenstrasse 30, 70599 Stuttgart, Germany Helmut Dalitz, Institute of Botany, University of Hohenheim, Garbenstrasse 30, 70599 Stuttgart, Germany Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    Afforestation and reforestation activities enjoy a prominent place on the policy agenda as potential tools to sequester carbon and for biomass production to mitigate climate change and restoring marginal lands. Two provenances (1 from Turkey and 1 from Lebanon) of the species Cedrus libani A. Rich. and two provenances (1 from Morocco and 1 from France) of the species Cedrus atlantica (Endl.) Carrier were studied to evaluate to what degree these trees were suitable for afforestation in arid regions of Italy. We measured, seasonal stomatal conductance ( g s ), foliar morphology, foliar carbon isotopic composition (δ 13 C), growth, and assessed bud phenology in a split plot trials. Bud phenology showed that the Turkish and Lebanon provenances of C. libani gave rise to earlier buds (earlier bud provenances) than the Moroccan and French provenances of C. atlantica (later bud provenances) with a mean difference of 23.2 days. Both provenances showed similar bud phenology and seasonal stomatal conductance ( g s ) especially in April–May (earlier bud provenances) and June (later bud provenances). The foliar δ 13 C was negatively correlated with g s in both the earlier bud provenances (i.e., an increase in g s was accompanied by decreasing foliar δ 13 C values) and the later bud provenances. The stomatal conductance values measured over a growth season showed significant correlations with daily means of both temperature and relative humidity. Hence g s in the earlier bud provenances was correlated with daily temperature in spring, whereas correlations with relative humidity were found in later bud provenances in both late spring and summer. We concluded that the earlier bud provenances ( C. libani ) are not suitable in areas affected by both summer drought and late spring frosts, whereas the later bud provenances ( C. atlantica ) are more suitable to be used in future afforestation plans due to their greater tolerance to summer drought. Content Type Journal Article Category Original Paper Pages 1-7 DOI 10.1007/s00468-012-0692-9 Authors Giovanni di Matteo, CRA-PLF, Agricultural Research Council, Research Unit for Wood Production Outside Forests, Via Valle della Quistione 27, 00166 Rome, Italy Marco Riccardi, CRA-PLF, Agricultural Research Council, Research Unit for Wood Production Outside Forests, Via Valle della Quistione 27, 00166 Rome, Italy Francesco Righi, CRA-PLF, Agricultural Research Council, Research Unit for Wood Production Outside Forests, Via Valle della Quistione 27, 00166 Rome, Italy Ernesto Fusaro, CRA-PLF, Agricultural Research Council, Research Unit for Wood Production Outside Forests, Via Valle della Quistione 27, 00166 Rome, Italy Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung: Context    Fir species are mainly distributed across the high latitudes, preferring cold climates. The phylogeographic origins of those subtropical fir species that occur in low latitudes in southern China remain elusive, as does the nature of any inter-lineage hybridization. Aims    In fir species, mitochondrial DNA (mtDNA) is maternally inherited and chloroplast DNA (cpDNA) is paternally inherited, and the genetic variations in the two make them particularly useful for examining species’ hybridizations and evolutionary histories. Materials and methods    We sequenced four DNA fragments: two of mtDNA and two of cpDNA for 161 individuals from four subtropical endangered fir species ( Abies beshanzuensis , Abies ziyuanensis , Abies yuanbaoshanensis , and Abies fanjingshanensis ) and two more northerly distributed ones ( Abies recurvata and Abies fargesii ) from central and southwest China. Results    Three mitotypes and four chlorotypes were recovered from the four southern species. In most populations, individuals share a single fixed mitotype and chlorotype. Three mitotypes clustered into two distinct clades, each associated with one of the northern species examined. For four chlorotypes, one occurred in A. ziyuanensis , A. beshanzuensis , A. fargesii , and A. recurvata , another in A. ziyuanensis and A. recurvata , the remaining two differed from others by two mutations exclusively in A. fanjingshanenis and A. yuanbaoshanensis. Conclusion    Phylogeographic origins of the subtropical fir species are complex, and genetic admixtures occurred during the evolutionary history of A. ziyuanensis . The genotyped populations further provide basic frames for genetic delimitation and effective conservation of these endangered species in the future. Content Type Journal Article Category Original Paper Pages 1-8 DOI 10.1007/s13595-011-0170-3 Authors Yanling Peng, Molecular Ecology Group, State Key Laboratory of Grassland Farming System, College of Earth and Environmental Sciences, Lanzhou University, Lanzhou, 730000 China Shuming Yin, Molecular Ecology Group, State Key Laboratory of Grassland Farming System, College of Earth and Environmental Sciences, Lanzhou University, Lanzhou, 730000 China Jing Wang, Molecular Ecology Group, State Key Laboratory of Grassland Farming System, College of Earth and Environmental Sciences, Lanzhou University, Lanzhou, 730000 China Bin Tian, Molecular Ecology Group, State Key Laboratory of Grassland Farming System, College of Earth and Environmental Sciences, Lanzhou University, Lanzhou, 730000 China Guangpeng Ren, Molecular Ecology Group, State Key Laboratory of Grassland Farming System, College of Earth and Environmental Sciences, Lanzhou University, Lanzhou, 730000 China Qiuhong Guo, Molecular Ecology Group, State Key Laboratory of Grassland Farming System, College of Earth and Environmental Sciences, Lanzhou University, Lanzhou, 730000 China Jianquan Liu, Molecular Ecology Group, State Key Laboratory of Grassland Farming System, College of Earth and Environmental Sciences, Lanzhou University, Lanzhou, 730000 China Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560

Beschreibung: Context and aim    This study aimed to examine the effect of the tension wood G‐layer on the viscoelastic properties of wood. Methods    Tension wood and opposite wood samples were obtained from six French Guianese tropical rainforest species ( Sextonia rubra , Ocotea guyanensis , Inga alba , Tachigali melinoni , Iyranthera sagotiana and Virola michelii ); the tension wood of the former three of these species had a G‐layer, whilst the tension wood from the latter three had no G‐layer. Tensile dynamic mechanical analysis (DMA) was performed on green never dried wood samples in the longitudinal direction with samples submerged in a water bath at a temperature (30°C) and frequency (1 Hz) representative of the conditions experienced by wood within a living tree. Then, DMA was repeated with samples conditioned to an air-dried state. Finally, samples were oven-dried to measure longitudinal shrinkage. Results    Tension wood did not always have a higher longitudinal storage (elastic) modulus than opposite wood from the same tree regardless of the presence or absence of a G‐layer. For the species containing a G‐layer, tension wood had a higher damping coefficient and experienced a greater longitudinal shrinkage upon drying than opposite wood from the same species. No difference was found in damping coefficients between tension wood and opposite wood for the species that had no G‐layer. Conclusion    It is proposed that the different molecular composition of the G-layer matrix has an influence on the viscoelasticity of wood, even if a biomechanical gain is not yet clear. This study shows that rheological properties and longitudinal shrinkage can be used to detect the presence of a G‐layer in tension wood. Content Type Journal Article Category Original Paper Pages 1-10 DOI 10.1007/s13595-011-0164-1 Authors J. Paul McLean, Laboratoire de Mécanique et Génie Civil (LMGC), Université Montpellier 2, CNRS, Montpellier, France Olivier Arnould, Laboratoire de Mécanique et Génie Civil (LMGC), Université Montpellier 2, CNRS, Montpellier, France Jacques Beauchêne, UMR Ecologie des Forêts de Guyane (ECOFOG), CIRAD, Kourou, French Guiana Bruno Clair, Laboratoire de Mécanique et Génie Civil (LMGC), Université Montpellier 2, CNRS, Montpellier, France Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560

Beschreibung: Context   The past management of Pinus brutia forests in Lebanon has led to diverse stand structures that cannot be easily classified as even-aged (EA) or uneven-aged (UA). Most stands are between these stand types, and they may be called as “semi-even-aged”. This is a very common characteristic throughout the Mediterranean conifer forests and makes the choice between the EA and UA approaches problematic, in both management and modelling. However, previous research has devoted little attention to the performance of growth and yield models when applied to transitional stand structures. Aims   The aim of this study was to find the best modelling approach and to recommend equations for simulating the dynamics of the semi-even-aged P. brutia stands of Lebanon on an individual-tree basis. Methods   Fifty sample plots were measured in Lebanon. Individual-tree growth models were fitted to the whole dataset using either UA or EA modelling approach. Models were also fitted using two sub-samples containing the most EA and the most UA plots. The performance and accuracy of the two modelling approaches were evaluated in all three datasets. Results   The article provides the first complete growth model for uneven-aged P. brutia stands. The EA sub-models presented better statistical fitting. However, the UA sub-models enabled more accurate predictions of wood production and were almost as good as the EA sub-models when predicting stand dynamics of the EA plots. The EA approach provided poor predictions, and the errors were high when it was applied to UA stands. Conclusions   In structurally complex stands, the UA modelling approach is to be preferred since it predicts the whole stand dynamics more accurately and enables simulations of a broader range of silvicultural treatments. Content Type Journal Article Category Original Paper Pages 1-11 DOI 10.1007/s13595-011-0171-2 Authors Sergio de-Miguel, Faculty of Science and Forestry, University of Eastern Finland, P.O. Box 111, 80101 Joensuu, Finland Timo Pukkala, Faculty of Science and Forestry, University of Eastern Finland, P.O. Box 111, 80101 Joensuu, Finland Nabil Assaf, Paris Sorbonne University (Paris IV), 1Rue Victor Cousin, 75005 Paris, France José Antonio Bonet, Centre Tecnològic Forestal de Catalunya (CTFC), Ctra. Sant Llorenç de Morunys, km 2, 25280 Solsona, Spain Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560

Beschreibung: Introduction   The logging of several spruce plantations is planned for the next years in the Eifel National Park (Western Germany). To understand the ecological mechanisms of spontaneous forest regeneration that follows these impacts, it is crucial to investigate the species composition and functional diversity of the buried germinable seeds in those stands. Methods   We analysed the soil seed bank by germination method and characterised germination dynamics and distribution of seedlings throughout the samples according to a sigmoid model and cumulative curves, respectively. To compare the proportions of functional and syntaxonomical groups between seed bank and aboveground vegetation, we applied the Fisher’s exact test. Additionally, we described the spatial distribution of the species in the seed bank according to semivariograms. Results   The studied seed bank reached a density of about 5,300 seed m −2 . Most of the species detected in the seed bank are related to open vegetation, forest fringes and early successional stages of forest regeneration. In spite of a low floristic similarity between seed bank and aboveground vegetation, the functional and syntaxonomical composition is very similar. Further studies considering the distribution of seeds in the soil and the changes of the seed bank composition during the regeneration process are required. Content Type Journal Article Category Original Paper Pages 1-11 DOI 10.1007/s13595-011-0174-z Authors Miguel Alvarez, INRES-Vegetation Ecology, Rheinische Friedrich-Wilhelms-Universität, Nußallee 9, 53115 Bonn, Germany Katja Seis, Institute of Silviculture, Albert-Ludwigs-Universität, Tennenbacherstr. 4, 79085 Freiburg, Germany Bodo Maria Möseler, INRES-Vegetation Ecology, Rheinische Friedrich-Wilhelms-Universität, Nußallee 9, 53115 Bonn, Germany Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560

Beschreibung: Context    Rotation length is known to affect timber quality in many plantation species, but its effect on the properties of Sitka spruce ( Picea sitchensis ) structural timber has not been quantified. Aim    Te purpose of this study was to compare selected wood properties and grade recovery of Sitka spruce structural timber cut from different radial positions within a log reflecting different cambial ages. Methods    Structural timber was sawn from 60 logs harvested from an 83-year-old stand in Great Britain. Five specimens were tested from each log: four from consecutive radial positions out from the pith and the fifth a random selection from outside the innermost 15 rings. Results    Mean modulus of elasticity and bending strength of timber from the outermost radial position were 51% and 41% greater, respectively, than for timber from adjacent to the pith. Wood density differed by 9% between these positions. The amount of distortion (spring, twist and bow), knot frequency and total knot area was significantly higher in timber cut from adjacent to the pith. Conclusion    Whilst longer rotations result in timber with improved mechanical properties and less distortion, economic and windthrow considerations may limit their implementation in Great Britain. Content Type Journal Article Category Original Paper Pages 1-10 DOI 10.1007/s13595-011-0168-x Authors John R. Moore, Forest Products Research Institute, Edinburgh Napier University, Edinburgh, EH10 5DT UK Andrew J. Lyon, Forest Products Research Institute, Edinburgh Napier University, Edinburgh, EH10 5DT UK Stefan Lehneke, Forest Products Research Institute, Edinburgh Napier University, Edinburgh, EH10 5DT UK Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560

Beschreibung: Context    Pinus radiata D. Don is the most widely planted conifer in the Inter-Andean Valleys of Bolivia. However, Bolivia lacks knowledge on stand dynamics and yield prediction of radiata pine, and the particular Bolivian conditions prevent a straightforward application of equations developed elsewhere. Aims    This study developed site index models, individual tree diameter increment models, individual tree height models, and self-thinning models for Bolivian P. radiata plantations. Methods    Dominant height was modeled using the algebraic difference approach. Diameter increment was modeled as a function of tree size, site index, and competition. Individual tree height was modeled as a function of tree diameter, dominant height, and dominant diameter. Self-thinning was modeled as a function of quadratic mean tree diameter. Results    By using the models, it can be calculated that the mean annual increment in volume with the optimal rotation length is less than 10 m 3 ha −1 on poor sites and 25 m 3 ha −1 on the best sites. Rotation lengths that maximize wood production are 25–30 years for very good sites and 35–40 years for poor sites. Conclusion    The models were assembled into a growth and yield simulator, allowing the simulation of stand development and making it possible to predict future yields and to compare alternative management schedules. Content Type Journal Article Category Original Paper Pages 1-9 DOI 10.1007/s13595-011-0162-3 Authors Gustavo Guzmán, Escuela de Ciencias Forestales, Universidad Mayor de San Simón, Final Av. Atahuallpa s/n, Temporal de Cala Cala, Barrio Prefectural, Cochabamba, Bolivia Timo Pukkala, Faculty of Science and Forestry, University of Eastern Finland, P.O. Box 111, 80101 Joensuu, Finland Marc Palahí, Mediterranean Regional Office, European Forest Institute, Sant Pau Historic Site, Santa Victoria Pavilion, St. Antoni M. Claret, 167, 08025 Barcelona, Spain Sergio de-Miguel, Faculty of Science and Forestry, University of Eastern Finland, P.O. Box 111, 80101 Joensuu, Finland Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560

Beschreibung: Context    Turkish red pine ( Pinus brutia Ten.) is widespread in the eastern Mediterranean Basin. In the late 1970s, four common gardens were established along steep altitudinal transects extending from the coast to about 1,200 m in the Taurus Mountains (Antalya, Turkey). Aims    The aim was to study the role of altitude in shaping Turkish red pine genetic diversity and population structure as well as to evaluate the existence of local adaptation along altitudinal gradients in this species. Methods    Genetic diversity and population structure were evaluated in replicated altitudinal gradients using chloroplast microsatellite (cpSSR) markers. Genetic differentiation for neutral markers was compared with quantitative differentiation for growth traits for the same populations evaluated at different altitudes. Results    Genetic differentiation among altitudinal groups was higher than among transects. A high portion of the genetic variance corresponded to families within populations (up to 10.75%). Overall quantitative genetic differentiation ( Q ST ) was higher than molecular differentiation in most test sites for all the traits and ages considered. Conclusion    Turkish red pine shows signatures of local adaptation to environmental gradients related to altitude. For forestry practices, such as selection of seed sources, both altitude and the family level of variation need to be considered. Content Type Journal Article Category Original Paper Pages 1-7 DOI 10.1007/s13595-011-0169-9 Authors Yusuf Kurt, Biology Department, Faculty of Sciences, Akdeniz University, 07058 Antalya, Turkey Santiago C. González-Martínez, Department of Forest Ecology and Genetics, CIFOR-INIA, P.O. Box 8111, 28080 Madrid, Spain Ricardo Alía, Department of Forest Ecology and Genetics, CIFOR-INIA, P.O. Box 8111, 28080 Madrid, Spain Kani Isik, Biology Department, Faculty of Sciences, Akdeniz University, 07058 Antalya, Turkey Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560

Beschreibung: Context   Forest scientists build models to simulate stand growth and forests dynamics. Dedicated computer tools are often developed to implement these models in order to run silvicultural scenarios and explore simulation results. Aims   Our objective was to encourage software reuse and simplify model implementation. Methods   The scheme was to develop a framework and methodology allowing to simplify the implementation, integration, simulation and comparison of forest models by providing a set of common and standard tools. Results   Capsis provides an open and modular software architecture based on various components, allowing to run forest growth simulations and display the results. The benefits of this framework are shown with the Samsara2 model, an individual-based and spatialised tree model. Capsis has been used successfully in many similar projects. In addition, the Capsis methodology defines how developers, modellers and end-users may interact. Conclusion   The Capsis framework facilitates collaborative and shared software development. Moreover, it is a powerful way to support scientific animation in the frame of forest science. Content Type Journal Article Category Original Paper Pages 1-13 DOI 10.1007/s13595-011-0140-9 Authors Samuel Dufour-Kowalski, INRA, UMR931 AMAP, Botany and Computational Plant Architecture, TA A-51/PS2, Boulevard de la Lironde, 34398 Montpellier Cedex 5, France Benoît Courbaud, CEMAGREF, Mountain Ecosystems Research Unit, 2 rue de la Papeterie, 38402 Saint Martin d’Hères, France Philippe Dreyfus, INRA, UR629 URFM, Écologie des Forêts Méditerranéennes, Site Agroparc, Domaine Saint Paul, 84914 Avignon Cedex 9, France Céline Meredieu, INRA, UMR1202 BIOGECO, 69 route d’Arcachon, 33612 Cestas Cedex, France François de Coligny, INRA, UMR931 AMAP, Botany and Computational Plant Architecture, TA A-51/PS2, Boulevard de la Lironde, 34398 Montpellier Cedex 5, France Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560

Beschreibung: Objectives    We examined canopy gap structure and regeneration patterns at the landscape scale using a combination of remote sensing and field-based surveys. Methods    The study was carried out in the forest reserve of Lom, an old-growth Fagus-Abies-Picea forest located within the Dinaric Alps in the north-western part of Bosnia and Herzegovina. A high-resolution (1-m panchromatic and 4-m multispectral) Kompsat-2 satellite image was orthorectified and classified through an unsupervised pixel-based classification using an artificial neural network method. Results    This approach allowed the identification of 650 canopy gaps, ranging in size from 32 to 1,776 m 2 . Only 20 intermediate to large gaps (〉250 m 2 ) were identified, and they were mainly present near the perimeter of the reserve. The origin of these large openings was associated with past human-caused disturbances or topographic conditions. The species composition of regeneration within large, human-caused gaps differed markedly from small gaps and non-gap sites in the core area of the reserve. Shade-intolerant species dominated the seedling and sapling layers in large openings. The landscape approach employed in this study confirmed the hypothesis that small gaps predominate at Lom, especially within the core area of the reserve. Content Type Journal Article Category Original Paper Pages 1-9 DOI 10.1007/s13595-011-0177-9 Authors Matteo Garbarino, Department of AGROSELVITER, University of Torino, Via L. da Vinci 44, 10095 Grugliasco, TO, Italy Enrico Borgogno Mondino, Department of DEIAFA, University of Torino, Via L. da Vinci 44, 10095 Grugliasco, TO, Italy Emanuele Lingua, Department of TESAF, University of Padova, Agripolis, Viale dell’Università 16, 35020 Legnaro, PD, Italy Thomas A. Nagel, Department of Forestry and Renewable Forest Resources, University of Ljubljana, Vecna Pot 83, 1000 Ljubljana, Slovenia Vojislav Dukić, Faculty of Forestry, University of Banja Luka, Vojvode Stepe Stepanovića 75a, 78000 Banja Luka, Republic of Bosnia and Herzegovina Zoran Govedar, Faculty of Forestry, University of Banja Luka, Vojvode Stepe Stepanovića 75a, 78000 Banja Luka, Republic of Bosnia and Herzegovina Renzo Motta, Department of AGROSELVITER, University of Torino, Via L. da Vinci 44, 10095 Grugliasco, TO, Italy Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560

Beschreibung:    Fingered citron ( Citrus medica L. var. sarcodactylis Swingle), a precious fruit ornamental plant, is sensitive to low temperature. Cold tolerance, evaluated by semi-lethal temperature, was lower in wild-type ‘Qingpi’ than in its mutant ‘Aihua’ trees obtained by γ-radiation. The full-length cDNAs of two genes encoding fatty acid desaturases involved in unsaturated fatty acid biosynthesis were isolated from the fingered citron leaves. The CmsFAD2 open reading frame (ORF) had 1,152 bp and was uninterrupted, encoding a polypeptide of 384 amino acids that showing 82% homology with the microsomal ω-6 desaturase CiFAD2 in Davidia involucrate . The CmsFAD8 ORF contained 1,373 bp and 7 introns, encoding a polypeptide of 458 amino acids showing 76% homology with the plastidial ω-3 desaturase BpFAD8 in Betula pendula . CmsFAD2 was expressed highly in leaves but low in roots and flowers, while CmsFAD8 was obviously expressed in three tissues. Compared with control group (28°C), the expression of CmsFAD2 and CmsFAD8 in leaves of two genotypes was significantly induced at 6°C. The increase of CmsFAD2 and CmsFAD8 was earlier and larger in cold-tolerant ‘Aihua’ than in cold-sensitive ‘Qingpi’. The linolenic acid content increased significantly in leaves of mutant ‘Aihua’ plants exposed to low temperature of 6°C. The results showed that a positive relationship between CmsFAD expression and genotype tolerance to cold may exist. Content Type Journal Article Category Original Paper Pages 1-9 DOI 10.1007/s00468-012-0695-6 Authors Ling Yang, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, 321004 Zhejiang, China Jin Ye, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, 321004 Zhejiang, China Wei-Dong Guo, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, 321004 Zhejiang, China Chang-Chun Wang, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, 321004 Zhejiang, China Hai-Tao Hu, College of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua, 321004 Zhejiang, China Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    Leaf gas-exchange, leaf and shoot anatomy, wood density and hydraulic conductivity were investigated in seedlings of Quercus suber L. grown for 15 months either at elevated (700 μmol mol −1 ) or normal (350 μmol mol −1 ) ambient atmospheric CO 2 concentrations. Plants were grown in greenhouses in a controlled environment: relative humidity 50% (±5), temperature similar to external temperature and natural light conditions. Plants were supplied with nutrients and two water regimes (WW, well watered; WS, water stress). After 6 months exposure to CO 2 enrichment an increase in photosynthetic rate, a decrease in stomatal conductance and a decrease in carbon isotope discrimination (Δ 13 C) were observed, along with enhanced growth and an increase in the number of branches and branch diameter. Over the same period, the shoot weight ratio increased, the root weight ratio decreased and the leaf weight ratio was unaffected. The specific leaf area increased due to an increase in total leaf thickness, mainly due to the palisade parenchyma and starch. However, after 9 and 15 months of elevated CO 2 exposure, the above-mentioned physiological and morphological parameters appeared to be unaffected. Elevated CO 2 did not promote changes in vessel lumen diameter, vessel frequency or wood density in stems grown in greenhouse conditions. As a consequence, xylem hydraulic efficiency remained unchanged. Likewise, xylem vulnerability to embolism was not modified by elevated CO 2 . In summary, elevated CO 2 had no positive effect on the ecophysiological parameters or growth of water stressed plants. Content Type Journal Article Category Original Paper Pages 1-13 DOI 10.1007/s00468-012-0691-x Authors M. Vaz, Departamento de Biologia, Instituto de Ciências Agrárias e Ambientais Mediterrânicas (ICAAM), Universidade de Évora, Apartado 94, 7002-554 Évora, Portugal H. Cochard, INRA, UMR 547 PIAF, 63100 Clermont-Ferrand, France L. Gazarini, Departamento de Biologia, Instituto de Ciências Agrárias e Ambientais Mediterrânicas (ICAAM), Universidade de Évora, Apartado 94, 7002-554 Évora, Portugal J. Graça, Instituto Superior de Agronomia, Universidade Técnica de Lisboa, Tapada da Ajuda, 1349-017 Lisbon, Portugal M. M. Chaves, Instituto Superior de Agronomia, Universidade Técnica de Lisboa, Tapada da Ajuda, 1349-017 Lisbon, Portugal J. S. Pereira, Instituto Superior de Agronomia, Universidade Técnica de Lisboa, Tapada da Ajuda, 1349-017 Lisbon, Portugal Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    The effect of stone dust deposition on the rate of transpiration in Shorea robusta was studied in three principal seasons in a polluted forest in comparison to an almost non-polluted forest. The extent of particulate pollution was determined by measuring suspended particulate matter in the air and dust fall on leaf surface. Macroscopic and microscopic leaf injury symptoms were studied. Scanning electron microscopic examination of leaf surfaces revealed a number of foliar anomalies. Qualitative determination of rate of transpiration in field condition was done by ‘cobalt chloride method’. It was found that transpiration was diminished as a result of foliar dust deposition which not only caused blockage of stomatal aperture but also physical damage to the leaf surface. Thus, particulate air pollution can be considered as one of the external factors regulating the rate of transpiration in plants. Content Type Journal Article Category Original Paper Pages 1-9 DOI 10.1007/s00468-012-0697-4 Authors Dulal C. Saha, Centre for Environmental Studies, Institute of Science, Visva-Bharati University, Santiniketan, 731235 India Pratap K. Padhy, Centre for Environmental Studies, Institute of Science, Visva-Bharati University, Santiniketan, 731235 India Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung: Context   Microfibril angle (MFA) is one of the key determinants of solid timber performance due to its strong influence on the stiffness, strength, shrinkage properties and dimensional stability of wood. Aims   The aim of this study was to develop a model for predicting MFA variation in plantation-grown Scots pine ( Pinus sylvestris L). A specific objective was to quantify the additional influence of growth rate on the radial variation in MFA. Methods   Twenty-three trees were sampled from four mature Scots pine stands in Scotland, UK. Pith-to-bark MFA profiles were obtained on 69 radial samples using scanning X-ray diffractometry. A nonlinear mixed-effects model based on a modified Michaelis–Menten equation was developed using cambial age and annual ring width as explanatory variables. Results   The largest source of variation in MFA (〉90 %) was within trees, while between-tree variation represented just 7 % of the total. Microfibril angle decreased rapidly near the pith before reaching stable values in later annual rings. The effect of ring width on MFA was greater at higher cambial ages. Conclusion   A large proportion of the variation in MFA was explained by the fixed effects of cambial age and annual ring width. The final model is intended for integration into growth, yield and wood quality simulation systems. Content Type Journal Article Category Original Paper Pages 1-10 DOI 10.1007/s13595-012-0248-6 Authors David Auty, Forest Research, Roslin, Midlothian, EH25 9SY Scotland, UK Barry A. Gardiner, Forest Research, Roslin, Midlothian, EH25 9SY Scotland, UK Alexis Achim, Département des sciences du bois et de la forêt, Université Laval, Québec, G1V 0A6 Canada John R. Moore, Scion (New Zealand Forest Research Institute Limited), Private Bag 3020, Rotorua, 3046 New Zealand Andrew D. Cameron, University of Aberdeen, Cruickshank Building, St Machar Drive, Aberdeen, AB24 3UU Scotland, UK Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560

Beschreibung:    At present, acid rain has become one of the top ten global environmental issues. Acid rain causes slower growth, injury, or decline of forests. Some dramatic effects on forests have been observed in south China since the late 1970s and the situation is deteriorating. We carried out a comparative proteomic analysis on Pinus massoniana Lamb, a staple tree species widely distributed in middle and south China to gain a better understanding of tree response to acid rain at molecular level. Two-year-old P. massoniana saplings were treated with simulated AR (SiAR) or control solution, respectively, for 8 months. The changes in total protein profile of P. massoniana leaves were studied using two-dimensional differential gel electrophoresis (2D-DIGE). Among the total protein spots reproducibly detected on each gel, 65 spots representing 28 proteins were identified to be differentially regulated. These proteins were annotated in various biological functions, such as photosynthesis and energy metabolism, secondary metabolism, protein stability, amino acid and nitrogen metabolism and defense. Down-regulation of four key enzymes in the Calvin cycle identified that biomass loss by SiAR was mainly due to the inhibition of carbon fixation. Primary energy metabolisms involved in sucrose biosynthesis, glycolytic pathway and Krebs cycle, etc., were also disturbed after SiAR treatment. Specifically, most of up-regulated proteins were related to secondary metabolism, protein stability and defense, suggesting that in response to SiAR stress, plants started a variety of metabolic pathways to prevent cells from damage. Different from the herbaceous plants suffering SiAR, it revealed that secondary metabolites in P. massoniana play pivotal roles against SiAR. Protemoic techniques were demonstrated a reliable and robust tool to expand our understanding of differentially expressed proteins associated with acid rain stress on P. massoniana . Functional analysis of these proteins further revealed biochemical and physiological basis of the plant in response to acid rain and would provide strategies for breeding new acid rain tolerant tree species. To our knowledge, it is the first proteome report on the forest plant suffering long-term acid rain stress. Content Type Journal Article Category Original Paper Pages 1-13 DOI 10.1007/s00468-012-0799-z Authors Xiaoqin Wang, College of Biological Science and Engineering, Beijing University of Agriculture, Beijing, 102206 China Zheng Liu, College of Life Sciences, Hebei University, Baoding, 071002 China Li Niu, Xiamen University, Xiamen, 361005 China Bin Fu, Xiamen University, Xiamen, 361005 China Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    Natural hybridization commonly produces individuals with intermediate morphological and genetic characteristics, but their response to environmental stress is still uncertain, with some studies showing that transgressive performance would be common. Prosopis chilensis and Prosopis flexuosa are the most important tree species from Arid Chaco, South-America. Both species occupy different ecological niches in terms of water availability. Genetic and morphological studies have demonstrated the existence of interspecific hybrids in contact areas between these species. Hybrids are characterized by clear intermediate morphological characteristics, which have taxonomical value, and genetic structure compared to both parental species. We studied mechanisms implicated in drought stress tolerance in seedlings of P. chilensis , P. flexuosa and their interspecific hybrids trying to elucidate if hybrids have a morpho-physiological, growth and survival intermediate response to drought compared to differential parental responses or if they out-perform both parental species when subjected to drought. Our results suggest that hybridization does not result in individuals with intermediate mechanisms related to drought resistance, but with a unique trait combination leading to high growth when water availability is high (similar to the most vulnerable parental species) and high survival under drought stress (similar to the more resistant parental species). Certain uncoupling between symplastic and apoplastic resistence to drought was observed in hybrids, as well as decreased physiological-wood anatomical plasticity compared to parental species. The long-term consequences in terms of adaptive response to drought of this particular trait combination of hybrids remain still unknown. Content Type Journal Article Category Original Paper Pages 1-12 DOI 10.1007/s00468-012-0798-0 Authors Diego A. López Lauenstein, Instituto de Fisiología y Recursos Genéticos Vegetales (IFRGV) Instituto Nacional de Tecnología Agropecuaria (INTA), Camino a 60 cuadras Km 5.5, Córdoba, Argentina María E. Fernández, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina Aníbal R. Verga, Instituto de Fisiología y Recursos Genéticos Vegetales (IFRGV) Instituto Nacional de Tecnología Agropecuaria (INTA), Camino a 60 cuadras Km 5.5, Córdoba, Argentina Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung: Context   We investigated the relationships between decay classes, morphological characteristics and chemical compounds in Abies alba Mill. and Fagus sylvatica L. stumps in two forest stands in the central Apennines (Italy). The analysis of deadwood decomposition is important in estimating carbon sequestration potential and carbon residence time in forest ecosystems. In addition, deadwood decomposition affects nutrient cycling and microhabitat distribution. Aims   The overall aim of this study was to investigate the decomposition processes in a mountainous Mediterranean ecosystem, and specifically to assess changes in chemical variables (lignin, cellulose, carbon and nitrogen content) in deadwood during the decomposition process, in relation to decay classes and to the species. Methods   Cross-sections were collected from stumps. Samples were assigned to visually discernible decay classes, and cellulose, lignin and carbon (C) and nitrogen (N) content in relation to total dry mass were analysed during the decay process. Results   Results showed how C/N ratio decreased over decades due to an increase in nitrogen content. On the contrary, carbon concentration in stumps remained substantially stable. Lignin degraded slowly in comparison with cellulose and differences between species were observed. Conclusion   The hypothesis that the conifer species would decompose faster than deciduous species did not prove correct. The slower decay of lignin compared to cellulose suggested that lignin could be an important long-term source of soil organic carbon, and that this process could be greatly affected by forest species mixtures. Finally, decomposition processes in the investigated montane–Mediterranean forests were definitely faster than in the colder climates of northern Europe. Content Type Journal Article Category Original Paper Pages 1-11 DOI 10.1007/s13595-012-0230-3 Authors F. Lombardi, Dipartimento di Bioscienze e Territorio, Laboratorio EcoGeoFor, Università degli Studi del Molise, Contrada Fonte Lappone, 86090 Pesche, IS, Italy P. Cherubini, Landscape Dynamics Unit—Dendroecology, WSL Swiss Federal Research Institute of Forest, Snow and Landscape, 8903 Birmensdorf, Switzerland R. Tognetti, Dipartimento di Bioscienze e Territorio, Laboratorio EcoGeoFor, Università degli Studi del Molise, Contrada Fonte Lappone, 86090 Pesche, IS, Italy C. Cocozza, Dipartimento di Bioscienze e Territorio, Laboratorio EcoGeoFor, Università degli Studi del Molise, Contrada Fonte Lappone, 86090 Pesche, IS, Italy B. Lasserre, Dipartimento di Bioscienze e Territorio, Laboratorio EcoGeoFor, Università degli Studi del Molise, Contrada Fonte Lappone, 86090 Pesche, IS, Italy M. Marchetti, Dipartimento di Bioscienze e Territorio, Laboratorio EcoGeoFor, Università degli Studi del Molise, Contrada Fonte Lappone, 86090 Pesche, IS, Italy Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560

Beschreibung:    Estimation of total leaf area (LA T ) is important to express biochemical properties in plant ecology and remote sensing studies. A measurement of LA T is easy in broadleaf species, but it remains challenging in coniferous canopies. We proposed a new geometrical model to estimate Norway spruce LA T and compared its accuracy with other five published methods. Further, we assessed variability of the total to projected leaf area conversion factor (CF) within a crown and examined its implications for remotely sensed estimates of leaf chlorophyll content ( C ab ). We measured morphological and biochemical properties of three most recent needle age classes in three vertical canopy layers of a 30 and 100-year-old spruce stands. Newly introduced geometrical model and the parallelepiped model predicted spruce LA T with an error 〈5 % of the average needle LA T , whereas two models based on an elliptic approximation of a needle shape underestimated LA T by up to 60 %. The total to projected leaf area conversion factor varied from 2.5 for shaded to 3.9 for sun exposed needles and remained invariant with needle age class and forest stand age. Erroneous estimation of an average crown CF by 0.2 introduced an error of 2–3 μg cm −2 into the crown averaged C ab content. In our study, this error represents 10–15 % of observed crown averaged C ab range (33–53 μg cm −2 ). Our results demonstrate the importance of accurate LA T estimates for validation of remotely sensed estimates of C ab content in Norway spruce canopies. Content Type Journal Article Category Original Paper Pages 1-11 DOI 10.1007/s00468-012-0774-8 Authors Lucie Homolová, Laboratory of Geo-Information Science and Remote Sensing, Wageningen University, Droevendaalsesteeg 3, 6708 PB Wageningen, The Netherlands Petr Lukeš, Global Change Research Centre, Academy of Sciences of the Czech Republic, Bělidla 986/4a, 60300 Brno, Czech Republic Zbyněk Malenovský, Remote Sensing Laboratories, Department of Geography, University of Zürich, Winterthurerstrasse 190, 8057 Zurich, Switzerland Zuzana Lhotáková, Department of Experimental Plant Biology, Faculty of Science, Charles University in Prague, Viničná 5, Prague, Czech Republic Věroslav Kaplan, Global Change Research Centre, Academy of Sciences of the Czech Republic, Bělidla 986/4a, 60300 Brno, Czech Republic Jan Hanuš, Global Change Research Centre, Academy of Sciences of the Czech Republic, Bělidla 986/4a, 60300 Brno, Czech Republic Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    In the context of global warming, it is of high importance to assess the influence of climatic change and geographic factors on the radial growth of high-elevation trees. Using tree-ring data collected from four stands of Qilian juniper ( Juniperus przewalskii Kom. ) across an altitudinal gradient in the central Qilian Mountains, northwest China, we compared the radial growth characteristics and climate–growth relationships at different elevations. Results indicated that there was little difference in the tree-ring parameters of the four chronologies. Correlation analyses both for unfiltered and 10-year high-passed data of monthly climatic variables and chronologies were presented to investigate the climatic forcing on tree growth, and results revealed that the correlation patterns were consistent among the four sites, especially for high-passed data. We employed the principal components analysis method to obtain the first principal component (PC1) of the four chronologies and computed the correlations between PC1 and climate factors. The PC1 correlated significantly with winter (November–January) temperature, prior August and current May temperature, and precipitation in the previous September and current January and April, indicating that tree growth in this region was mainly limited by cold winter temperature and drought in early growing season and prior growing season (prior August and September). However, the climate–growth relationships were unstable; with an increase in temperature, the sensitivity of tree growth to temperature had decreased over the past few decades. Considering the instability of the climate–growth relationships, climate reconstructions based on tree rings in the study area should be approached with more caution. Content Type Journal Article Category Original Paper Pages 1-10 DOI 10.1007/s00468-012-0776-6 Authors Linlin Gao, Key Laboratory of Western China’s Environmental Systems (Ministry of Education), Research School of Arid Environment and Climate Change, Lanzhou University, Lanzhou, 730000 China Xiaohua Gou, Key Laboratory of Western China’s Environmental Systems (Ministry of Education), Research School of Arid Environment and Climate Change, Lanzhou University, Lanzhou, 730000 China Yang Deng, Key Laboratory of Western China’s Environmental Systems (Ministry of Education), Research School of Arid Environment and Climate Change, Lanzhou University, Lanzhou, 730000 China Wenhuo Liu, Key Laboratory of Western China’s Environmental Systems (Ministry of Education), Research School of Arid Environment and Climate Change, Lanzhou University, Lanzhou, 730000 China Meixue Yang, State Key Laboratory of Cryospheric Sciences, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou, 730000 China Zhiqian Zhao, Key Laboratory of Western China’s Environmental Systems (Ministry of Education), Research School of Arid Environment and Climate Change, Lanzhou University, Lanzhou, 730000 China Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    We assessed growth differences and the foliar traits underpinning production in paired samples of juvenile American beech ( Fagus grandifolia Ehrh.) that originated from seed versus root sprouts. Root sprouts had significantly greater relative extension growth rate and slightly greater leaf mass per unit area compared to seed-derived individuals, but neither light-saturated net photosynthetic rate nor foliar chlorophyll and nitrogen concentrations differed significantly between paired seedlings and sprouts. The greater height growth rate of saplings originating as root sprouts does not result from differing foliar function, but rather depends on translocation of assimilates from the parent tree to sustain this unusual and ecologically important dual regeneration strategy in American beech. Content Type Journal Article Category Short Communication Pages 1-4 DOI 10.1007/s00468-012-0781-9 Authors Emad Farahat, Department of Biology, McGill University, 1205 Avenue Dr. Penfield, H3A1B1 Montréal, QC, Canada Martin J. Lechowicz, Department of Biology, McGill University, 1205 Avenue Dr. Penfield, H3A1B1 Montréal, QC, Canada Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    European beech ( Fagus sylvatica L.) covers a large area mainly in the colline and montane ranges in Europe, and a drier and warmer climate, as expected for the coming decades, is likely to alter its distribution. So far, an altitudinal shift has been projected using a variety of modelling approaches. However, we lack knowledge about the climatic and edaphic factors that control the growth and competitive behaviour of beech at its dry distribution limit. We applied and further developed dendroecological methods to study the drought response and sensitivity pattern of beech at sites with different moisture regimes. We compared three pairs of sites from different geographical regions near the dry distribution limit of beech in Switzerland, consisting of a dry and mesic site each. Radial growth differed between mesic and dry sites, in that average ring-width at mesic sites was around double the width at dry sites. For the whole study period (1930–2006), the sites with the lowest available soil water capacity (AWC) were found to respond most sensitively to drought. However, in recent years, sites with higher AWC have shown increasing drought sensitivity, i.e. they have responded even more strongly to drought than the dry sites. This change in sensitivity corresponds to a seasonal shift in drought response at mesic sites, with a change in the months showing significant drought response in all three studied regions compared with the past. Even though dry sites generally displayed a larger number of negative pointer years than mesic sites, it appears that the frequency of pointer years has increased at mesic sites, i.e. they have become more sensitive particularly in the last quarter of the twentieth century. Yet, the frequency of pointer years at the dry sites has remained fairly constant. These results indicate that beech trees near their dry distribution limit are adapted to extreme conditions already, while changes in the growth patterns of beech under mesic conditions have to be expected. Content Type Journal Article Category Original Paper Pages 1-11 DOI 10.1007/s00468-012-0786-4 Authors P. Weber, Swiss Federal Research Institute WSL, Birmensdorf, Switzerland H. Bugmann, Forest Ecology, Institute of Terrestrial Ecosystems, ETH Zürich, Zurich, Switzerland A. R. Pluess, Ecosystem Management, Institute of Terrestrial Ecosystems, ETH Zürich, Zurich, Switzerland L. Walthert, Swiss Federal Research Institute WSL, Birmensdorf, Switzerland A. Rigling, Swiss Federal Research Institute WSL, Birmensdorf, Switzerland Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung: Special topic: integrating modelling and experimentation Content Type Journal Article Category Editorial Pages 1-4 DOI 10.1007/s00468-012-0778-4 Authors R. Matyssek, Ecophysiology of Plants, Technische Universität München, von-Carlowitz Platz 2, Weihenstephan, 85354 Freising, Germany G. M. J. Mohren, Forest Ecology and Forest M anagement Group, Centre for Ecosystem Studies, Wageningen University, P.O. Box 47, 6700 AA Wageningen, The Netherlands Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung: Context    Implementing nature-based silviculture requires understanding the structural and compositional changes that occur in forested stands under known disturbance types and intensities. Aims    The objectives were to assess the (a) resistance of hardwood forests to change, (b) their trajectory of recovery following disturbance, and (c) how closely resulting forests resemble original forests. Methods    We characterized tree structure and composition at three points in time (pre-disturbance, 1-year post-disturbance, and ∼15 years following disturbance) along a harvesting disturbance gradient created by removing trees in different forest canopy strata. Results    Significant differences to pre-disturbance conditions were noted immediately post-harvest for tree basal area, density, species richness, and tree species composition; treatment differences were observed for all parameters except diversity. Plots exposed to the least extreme harvesting disturbances (cutting small and intermediate trees) had returned to pre-disturbance conditions for most parameters after 15 years, while the most extreme harvesting disturbance (cutting large trees) had not yet recovered. Conclusions    Although not initially resistant, Central Appalachian eastern hardwoods are fairly resilient to the removal of trees in the subcanopy or a mixture of the subcanopy and canopy; only the removal of solely canopy trees (i.e., high grading) and complete removal (i.e., clearcutting) appear to impose harvesting disturbances to which these forests may not be resilient. Content Type Journal Article Category Original Paper Pages 1-9 DOI 10.1007/s13595-012-0242-z Authors Eric K. Zenner, School of Forest Resources, The Pennsylvania State University, 305 Forest Resources Building, University Park, PA 16802, USA Yvette L. Dickinson, School of Forest Resources, The Pennsylvania State University, 117 Forest Resources Building, University Park, PA 16802, USA JeriLynn E. Peck, School of Forest Resources, The Pennsylvania State University, 117 Forest Resources Building, University Park, PA 16802, USA Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560

Beschreibung:    Individual tree-ring width chronologies and mean chronologies from Pinus tabuliformis Carr. (Chinese pine) and Sabina przewalskii Kom. (Qilian juniper) tree cores were collected and analyzed from two sites in the eastern Qilian Mountains of China. The chronologies were used to analyze individual and time-varying tree-ring growth to climate sensitivity with monthly mean air temperature and total precipitation data for the period 1958–2008. Climate–growth relationships were assessed with correlation functions and their stationarity and consistency over time were measured using moving correlation analysis. Individuals’ growth–climate correlations suggested increased percentages of individuals are correlated with certain variables (e.g., current June temperature at the P. tabuliformis site; previous June, December and current May temperature and May precipitation at the S. przewalskii site). These same climatic variables also correspond to the mean chronology correlations. A decreased percentage of individuals correlated with these climatic variables indicates a reduced sensitivity of the mean chronology. Moving correlation analysis indicated a significant change over time in the sensitivity of trees to climatic variability. Our results suggested: (1) that individual tree analysis might be a worthwhile tool to improve the quality and reliability of the climate signal from tree-ring series for dendroclimatology research; and (2) time-dependent fluctuations of climate growth relationships should be taken into account when assessing the quality and reliability of reconstructed climate signals. Content Type Journal Article Category Original Paper Pages 1-12 DOI 10.1007/s00468-012-0772-x Authors Fen Zhang, Key Laboratory of Western China’s Environmental Systems (MOE), Research School of Arid Environment and Climate Change, Lanzhou University, Lanzhou, 730000 China Xiaohua Gou, Key Laboratory of Western China’s Environmental Systems (MOE), Research School of Arid Environment and Climate Change, Lanzhou University, Lanzhou, 730000 China Wenhuo Liu, Key Laboratory of Western China’s Environmental Systems (MOE), Research School of Arid Environment and Climate Change, Lanzhou University, Lanzhou, 730000 China D. F. Levia, Departments of Geography and Plant and Soil Sciences, University of Delaware, Newark, DE 19716, USA Yingjun Li, Taiyaun Normal University Research Center for Scientific Development in Fenhe River Valley, Taiyuan, 030012 China Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    Dendrochronological research in Southeast Asia is under development; however, the amount of tress with potential for dendrochronological studies is restricted. For example, teak trees from India, Myanmar, Thailand, and Java are valuable dendrochronologic studies for ready climate response. Teak from Java is best suited for studying the El Niño-Southern Oscillation and sea-surface temperatures, whereas Indian teak is used to reconstruct periods of drought in India. Further, Thai teak and Vietnamese cypress trees captured the long drought period that led to the demise of the Angkor reign (fourteenth–fifteenth century). Diverse techniques including anatomical observation, cambial markings, cell differentiation, and isotopic analysis prove the age and growth of invisible tropical tree rings. A number of invisible growth rings in trees from both tropical and subtropical forests have been identified, resulting in the advancement of dendrochronology. Climate change is a substantial challenge for most living things and natural resources. A greater understanding of tree species adaptation in this region is necessary. The understanding of long-term paleoclimate can be gained by researching old samples and archaeological materials from this region. Content Type Journal Article Category Review Pages 1-16 DOI 10.1007/s00468-012-0775-7 Authors Nathsuda Pumijumnong, Faculty of Environment and Resource Studies, Mahidol University, Salaya, Phutthamonthon, Nakhon Pathom 73170, Thailand Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung: • Context   Corymbia F1 hybrids have high potential for plantation forestry; however, little is known of their reproductive biology and potential for genetic pollution of native Corymbia populations. • Aims   This study aims to quantify the influence of reproductive isolating barriers on the success of novel reciprocal and advanced generation Corymbia hybrids. • Methods   Two maternal taxa, Corymbia citriodora subsp. citriodora and Corymbia torelliana , were pollinated using five paternal taxa, C. citriodora subsp. citriodora , C. torelliana , one C. torelliana × C. citriodora subsp. citriodora hybrid and two C. torelliana × C. citriodora subsp. variegata hybrids. Pollen tube, embryo and seed development were assessed. • Results   Reciprocal hybridisation between C. citriodora subsp. citriodora and C. torelliana was successful. Advanced generation hybrids were also created when C. citriodora subsp. citriodora or C. torelliana females were backcrossed with F1 hybrid taxa. Prezygotic reproductive isolation was identified via reduced pollen tube numbers in the style and reduced numbers of ovules penetrated by pollen tubes. Reproductive isolation was weakest within the C. citriodora subsp. citriodora maternal taxon, with two hybrid backcrosses producing equivalent capsule and seed yields to the intraspecific cross. • Conclusions   High hybridising potential was identified between all Corymbia species and F1 taxa studied. This provides opportunities for advanced generation hybrid breeding, allowing desirable traits to be amplified. It also indicates risks of gene flow between plantation and native Corymbia populations. Content Type Journal Article Category Original Paper Pages 1-10 DOI 10.1007/s13595-012-0231-2 Authors Geoffrey R. Dickinson, Department of Agriculture Fisheries and Forestry—Queensland, P.O. Box 1054, Mareeba, QLD 4880, Australia Helen M. Wallace, University of the Sunshine Coast, Maroochydore DC, QLD 4558, Australia David J. Lee, University of the Sunshine Coast, Maroochydore DC, QLD 4558, Australia Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560

Beschreibung: Context   Silver fir is declining and dying at its southern margin on the Mediterranean area, where climate is expected to be warmer and drier. At a regional scale, silver fir seems to be vulnerable to drought, and at a forest stand scale, tree death seems to be distributed according to soil water availability. Aim   To understand the vulnerability of silver fir to drought, factors involved in the regulation of transpiration were assessed with respect to soil properties in order to document the spatial distribution of death rates. Methods   Soil properties were characterized by electric resistivity measurements. Sap flow density and predawn needle water potential were recorded on sampled trees during several years, and crown specific transpiration was estimated. In addition, the vulnerability of coarse roots and branches to cavitation was quantified. Results and conclusion   Trees growing on soils with a large water storage capacity were the most vulnerable to drought induced soil water deficits. Transpiration was down-regulated as soon as predawn water potential decreased. The vulnerability to cavitation was low, which protected the trees from run-away xylem embolism. Severe soil water deficits led to a rapid decrease of transpiration, which was still visible the following year. The drop-off in transpiration was mainly due to inner sap flow that almost ceased after the drought on all monitored trees. Our results suggest that root dynamic and the ability of roots to take up water were modified by soil water deficit over several years. Such a regulation scheme needs to be better documented and included in models to address silver fir forest responses to drought. Content Type Journal Article Category Original Paper Pages 1-13 DOI 10.1007/s13595-012-0229-9 Authors Marie Nourtier, UMR1114, Environnement Méditerranéen et Modélisation des AgroHydrosystèmes, INRA, Domaine Saint Paul, Site Agroparc, 84914 Avignon, France André Chanzy, UMR1114, Environnement Méditerranéen et Modélisation des AgroHydrosystèmes, INRA, Domaine Saint Paul, Site Agroparc, 84914 Avignon, France Maxime Cailleret, UR629, Écologie des Forêts Méditerranéennes, INRA, Domaine Saint Paul, Site Agroparc, 84914 Avignon, France Xie Yingge, UMR1114, Environnement Méditerranéen et Modélisation des AgroHydrosystèmes, INRA, Domaine Saint Paul, Site Agroparc, 84914 Avignon, France Roland Huc, UR629, Écologie des Forêts Méditerranéennes, INRA, Domaine Saint Paul, Site Agroparc, 84914 Avignon, France Hendrik Davi, UR629, Écologie des Forêts Méditerranéennes, INRA, Domaine Saint Paul, Site Agroparc, 84914 Avignon, France Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560

Beschreibung:    The branch autonomy principle has been referred to extensively for using branch cuvettes as a technique of studying ozone (O 3 ) effects within the canopy of adult forest trees. However, this principle may not hold in general regarding biochemical interactions between O 3 -impacted branches exposed inside cuvettes and neighbouring crown parts under the unchanged ambient O 3 regime. After reviewing relevant cuvette studies conducted to date, we will provide evidence that cuvette-exposed branches may serve, given awareness of outlined pre-requisites and restrictions, as surrogates for examining the crown-level response of trees to elevated O 3 regimes. Such a conclusion is based on the defence metabolism of branches, which seems to be autonomous to some extent from neighbouring crown sections. Cuvette studies may, therefore, be used to derive dose response functions as measures of O 3 sensitivity. On such grounds, also validation and improvement of stomatal O 3 uptake modelling becomes feasible. The branch-level approach, however, does not substitute whole-tree free-air O 3 fumigation and related flux assessments, as branches in view of representativeness and boundary layer characteristics represent one stage in scaling O 3 flux between leaf and tree level. Branch level-based flux scaling should be backed, therefore, by independent trunk sap-flow assessment techniques that offer derivation of FO 3 at the whole-tree level. Content Type Journal Article Category Original Paper Pages 1-10 DOI 10.1007/s00468-012-0715-6 Authors Gerhard Wieser, Division of Alpine Timberline Ecophysiology, Federal Research and Training Centre for Forests, Natural Hazards and Landscape, Rennweg 1, 6020 Innsbruck, Austria Rainer Matyssek, Ecophysiology of Plants, Technische Universität München, 85354 Freising, Germany Bernhard Götz, University of Applied Sciences, Hochschule für nachhaltige Entwicklung Eberswalde (FH), Botanical Garden, Am Zainhammer 5, 16225 Eberswalde, Germany Ludger Grünhage, Department of Plant Ecology, Justus-Liebig University Giessen, Heinrich-Buff-Ring 26, 35392 Giessen, Germany Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung: • Context   Many tree breeding programmes rely entirely on clonal seed orchards as the link between breeding activities and forestry, and are thereby also exposed to yearly fluctuations in the orchard crops. • Aims   The main objective was to study the impact of year and clone fluctuations in strobili production on genetic worth, as well as on genetic diversity, of 18 consecutive commercial seed orchard crops. • Methods   In a mature Abies nordmanniana clonal seed orchard, a yearly visual assessment of female and male strobili was carried out on a total of 18 clones (260 ramets), and coupled with clone breeding values. • Results   Despite large annual and clone variation, and year-by-clone interaction in strobili production, the orchard’s genetic worth was somewhat uniform when considering four evaluated traits in the 11 years of superior or medium crop size. These years accounted for 95% of the accumulated cone crop over the whole period (18 years). Noteworthy deviations were only seen in the seven poorest seed years, comprising the remaining 5% of the total cone crop, where genetic diversity measures were also low. • Conclusion   Avoiding small crop years seems to be a reasonable way to avoid fluctuations in the commercial seed orchard product. Content Type Journal Article Category Original Paper Pages 69-80 DOI 10.1007/s13595-011-0159-y Authors Ulrik B. Nielsen, Danish Centre for Forest, Landscape and Planning, University of Copenhagen, Rolighedsvej 23, 1958 Frederiksberg C, Denmark Ole K. Hansen, Danish Centre for Forest, Landscape and Planning, University of Copenhagen, Rolighedsvej 23, 1958 Frederiksberg C, Denmark Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560 Journal Volume Volume 69 Journal Issue Volume 69, Number 1

Beschreibung: • Context   This review paper provides an overview of approaches to which we may resort for handling the complex decision problems involving uncertainty and risk that climate change implies for forest managers. Modelling approaches that could support adaptive management strategies seem to be called for, not only as climate change denotes increased economic uncertainty but also because new and more reliable information becomes available as time passes and climate changes. • Aims   The paper (1) provides a broad overview of state-of-the-art methods for optimal decision making under risk and uncertainty in forestry and (2) elaborates on the possible use of these methods in adaptive forest management under climate change. • Method   A survey of the current literature is carried out to identify approaches and developments that may prove most promising in relation to different challenges to the adaptive management of forest ecosystems under climate change. • Results   Most studies focusing on changing, typically increasing, risks in forest management under climate change tend to build on existing approaches about changes in risk levels contingent on climate change scenarios. • Conclusion   Finally, we discuss what to emphasise in future studies to improve the understanding of adaptive forest management and decision support tools needed to cope with climate change. Content Type Journal Article Category Review Paper Pages 1-15 DOI 10.1007/s13595-011-0153-4 Authors Rasoul Yousefpour, Forest & Landscape, University of Copenhagen, Rolighedsvej 23, 1958 Frederiksberg C, Denmark Jette Bredahl Jacobsen, Forest & Landscape, University of Copenhagen, Rolighedsvej 23, 1958 Frederiksberg C, Denmark Bo Jellesmark Thorsen, Forest & Landscape, University of Copenhagen, Rolighedsvej 23, 1958 Frederiksberg C, Denmark Henrik Meilby, Forest & Landscape, University of Copenhagen, Rolighedsvej 23, 1958 Frederiksberg C, Denmark Marc Hanewinkel, Eidg. Forschungsanstalt WSL, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland Karoline Oehler, Regional Office EFICENT-OEF, European Forest Institute, Wonnhaldestr. 4, D-79100 Freiburg, Germany Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560 Journal Volume Volume 69 Journal Issue Volume 69, Number 1

Beschreibung:    Understanding spatiotemporal tree growth variability and its associations with climate can provide key insights into forest dynamics in the context of global climate change. Here, we conduct a comprehensive investigation on 64 ring-width chronologies across the entire Northwest (NW) China to understand the regional patterns of tree growth and climate–growth relationships. Using rotated principal component analysis and hierarchical clustering analysis, we found that tree growth was mainly determined by the climate and could be classified into nine groups. Most of the tree-ring chronologies in NW China showed high correlations with moisture conditions in the current and previous growing seasons. After removing age-related growth trends, inter-annual tree growth patterns are supposed to be mainly determined by climate and climate–growth relationships. Since climate–growth relationships for most tree-ring chronologies in this arid region are similar, patterns of tree growth are mainly determined by climate variability. Within each group, the strength of the common signal increases under extreme climate conditions. Thus, climate plays a more important role in determining tree growth in extreme climate conditions relative to the non-climate factors, leading to more coherent growth patterns. Content Type Journal Article Category Original Paper Pages 1-11 DOI 10.1007/s00468-012-0721-8 Authors Keyan Fang, Key Laboratory of Western China’s Environmental Systems (Ministry of Education), Research School of Arid Environment and Climate Change, Lanzhou University, Lanzhou, 730000 China Xiaohua Gou, Key Laboratory of Western China’s Environmental Systems (Ministry of Education), Research School of Arid Environment and Climate Change, Lanzhou University, Lanzhou, 730000 China Fahu Chen, Key Laboratory of Western China’s Environmental Systems (Ministry of Education), Research School of Arid Environment and Climate Change, Lanzhou University, Lanzhou, 730000 China Edward Cook, Tree-Ring Lab, Lamont-Doherty Earth Observatory of Columbia University, New York, NY 10964, USA Jinbao Li, International Pacific Research Center, School of Ocean and Earth Science and Technology, University of Hawaii, Honolulu, HI 96882, USA Yingjun Li, Key Laboratory of Western China’s Environmental Systems (Ministry of Education), Research School of Arid Environment and Climate Change, Lanzhou University, Lanzhou, 730000 China Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung: • Context   This research was conducted in a 62-year-old stone pine ( Pinus pinea L.) forest within the National Natural Reserve of the Roman Coast, Italy. Net under-canopy precipitation was measured between September 2004 and December 2008 in a unthinned and a thinned area of about 1 ha each. • Aims   The goals were to document and compare net under-canopy rainfall (throughfall and stemflow) in thinned and unthinned stands, and evaluate how the re-growth of tree crowns following thinning influences canopy interception. • Methods   Thinning was carried out during the winter of 2002 and reduced the number of trees by 56% and leaf area index (LAI) by 63%. Rainfall, throughfall, and stemflow were measured and analysed. • Results   Interception loss averaged 23% and 40% in the thinned and unthinned areas respectively, but difference decreased during larger rainfall events. Net under-canopy precipitation was always higher ( P  〈 0.001) in the thinned area, and showed a significant ( P  = 0.041) relationship with LAI. Stemflow was very low. • Conclusion   These results highlight the positive effect of thinning, which reduces water loss from precipitation caused by interception of rainfall in Mediterranean forests that have never been thinned. Thinning guarantees a greater flow of water under the canopy, particularly in the driest months and for lower amounts of rainfall, and improves stand growth rates. Content Type Journal Article Category Original Paper Pages 1323-1332 DOI 10.1007/s13595-011-0142-7 Authors Gianluigi Mazza, Research Centre for Silviculture, Agriculture Research Council, Viale S. Margherita 80, 52100 Arezzo, Italy Emilio Amorini, Research Centre for Silviculture, Agriculture Research Council, Viale S. Margherita 80, 52100 Arezzo, Italy Andrea Cutini, Research Centre for Silviculture, Agriculture Research Council, Viale S. Margherita 80, 52100 Arezzo, Italy Maria Chiara Manetti, Research Centre for Silviculture, Agriculture Research Council, Viale S. Margherita 80, 52100 Arezzo, Italy Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560 Journal Volume Volume 68 Journal Issue Volume 68, Number 8

Beschreibung: Introduction   Knowledge of vertical variation in hydraulic parameters would improve our understanding of individual trunk functioning and likely have important implications for modeling water movement to the leaves. Specifically, understanding how foliage area ( A l ), sapwood area ( A s ), and hydraulic specific conductivity ( k s ) vary with canopy position to affect leaf-specific conductivity (LSC) and whole-tree leaf-specific hydraulic conductance ( K l ) may explain some of the contrasting patterns of A l / A s reported in the literature. Objective   The general aim of the study was to characterize and compare the aboveground relationships between cumulative A l , A s , and k s for two Pacific Northwest coniferous species with contrasting sapwood areas to give insight into size-related design of trees for water transport through changes in LSC and K l . Results   The 230-year-old ponderosa pine ( Pinus ponderosa ) trees had slightly smaller basal diameters than the 102-year-old Douglas-fir ( Pseudostuga menziesii ) trees, but contained 85% sapwood at the base compared to 30% in Douglas-fir. At the tree base, there was no evidence that A l / A s decreased with tree age or with tree size. In both species, A l / A s of branches was significantly higher than A l / A s at the tree base, but it was not different from A l / A s measured in the trunks at the top of the tree. Douglas-fir had higher A l / A s at the base than did ponderosa pine (0.42 vs. 0.24 m 2 cm −2 ), similar patterns of change in A l / A s with height, and similar values of k s , such that LSC in Douglas-fir was 77% the value of LSC in ponderosa pine. Compensating changes to increase LSC between short and tall trees occurred through an increased in k s in tall trees but not through a reduction in A l . LSC increased logarithmically with branch path length or trunk path length whereas K l decreased significantly from top to base of old trees, but not between sections from old and young trees of similar cambial age. Conclusions   Even though ponderosa pine had three times more sapwood than Douglas-fir, this study revealed a common relationship of declining K l with increasing tree height and diameter between the two species, within age classes and among trees. There was no compensating decrease in A l / A s as trees got taller, which showed that a homeostasis in K l was not maintained during growth. The trend of higher allocation of biomass to sapwood over leaves in ponderosa pine is consistent with this species’ tendency to inhabit drier sites than Douglas-fir. Content Type Journal Article Category Original Paper Pages 17-27 DOI 10.1007/s13595-011-0154-3 Authors Jean-Christophe Domec, ENITAB, UMR 1220 TCEM, 33175 Gradignan, France Barbara Lachenbruch, Department of Forest Ecosystems and Society, Oregon State University, Corvallis, OR 97331, USA Michele L. Pruyn, Department of Biological Sciences, Plymouth State University, Plymouth, NH 03264, USA Rachel Spicer, Department of Botany, Connecticut College, New London, CT 06320, USA Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560 Journal Volume Volume 69 Journal Issue Volume 69, Number 1

Beschreibung:    Tree growth and form are both influenced by crown architecture and how it effects leaf distribution and light interception. This study examined the vertical distribution of foliage in 4-year-old plantation-grown Eucalyptus pilularis Sm. and E. cloeziana F. Muell. trees. Leaf area (LA) distribution was determined at two different sites using allometric approaches to determine LA in crown sections and for whole trees. Leaf area was distributed more towards the upper crowns when canopies had been closed for longer. Leaf area was also skewed more towards the upper crowns for Eucalyptus pilularis than E. cloeziana . These species differences were consistent with differences in vertical light availability gradients as determined by point quantum sensors. Leaf area of individual branches was highly correlated with branch cross-sectional area (CSA) and whole-tree LA was closely related to stem CSA. Branch-level allometric relationships were influenced by site and crown position. However, the general allometric equations between stem size and whole-tree leaf area could be applied across sites. Results from this study suggest that pruning of live branches in these species should follow species-specific guides for the timing and height of pruning to optimise the effects on stem growth and form. Content Type Journal Article Category Original Paper Pages 1-12 DOI 10.1007/s00468-012-0809-1 Authors Philip J. Alcorn, Research School of Biology, The Australian National University, Canberra, ACT 0200, Australia David I. Forrester, Institute of Silviculture, Freiburg University, 79085 Freiburg, Germany R. Geoff B. Smith, Forests NSW, PO Box J19, Coffs Harbour, NSW 2450, Australia Dane S. Thomas, Forests NSW, PO Box J19, Coffs Harbour, NSW 2450, Australia Ryde N. James, Fenner School of Environment and Society, The Australian National University, Canberra, ACT 0200, Australia Adrienne B. Nicotra, Research School of Biology, The Australian National University, Canberra, ACT 0200, Australia Jürgen Bauhus, Fenner School of Environment and Society, The Australian National University, Canberra, ACT 0200, Australia Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    The two main objectives of this research were to identify new S -RNase alleles in Iranian almond cultivars and to characterize naturally occurring mutations in these alleles that may cause self-compatibility. We investigated S genotypes of 22 Iranian almond cultivars using stylar RNase electrophoresis, PCR and DNA sequencing. We report six previously unidentified P. dulcis S -RNase alleles ( S 45 , S 46 , S 47 , S 48 , S 49 and S 50 ). Four of 12 tested S -RNases were found to be non-functional in vitro: S 49 , S 50 , S 24 / S na and S 25 / S 47 . Detected point mutations in the C3 coding region of S 49 - and S 50 -RNase, leading to the replacement of a highly conserved cysteine and histidine residues, are with the highest probability the reason of these S -RNases inactivity. Results also suggested that ten Iranian almond cultivars display unique S genotype. All presented data confirm Iranian cultivars as valuable almond sources which are of interest to almond breeding and conservation programs. Content Type Journal Article Category Original Paper Pages 1-14 DOI 10.1007/s00468-012-0803-7 Authors Akram Hafizi, Faculty of Agriculture, Department of Agronomy and Plant Breeding, Zanjan University, Zanjan, Iran Behrouz Shiran, Faculty of Agriculture, Department of Plant Breeding and Biotechnology, Shahrekord University, Shahrekord, Iran Bahram Maleki, Faculty of Agriculture, Department of Agronomy and Plant Breeding, Zanjan University, Zanjan, Iran Ali Imani, Sections of Horticulture, Agriculture and Natural Resources Research Centre of Karaj, Karaj, Iran Bojana Banović, Institute of Molecular Genetics and Genetic Engineering, University of Belgrade, Belgrade, Serbia Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    Protocols have been established to clone adult cork oak trees by somatic embryogenesis using semisolid medium. However, for economically viable mass propagation, embryogenic cultures in liquid medium need to be developed. In this study, suspension cultures were initiated from embryo clusters obtained by secondary embryogenesis on a gelled medium lacking plant growth regulators. After 6 days of culture, these embryo clusters generated high cell density suspensions that also contained small organized structures (embryos and embryogenic clumps). As the culture duration increased, tissue necrosis and fewer embryogenic structures were observed and the establishment of suspension cultures failed. An alternative method was found adequate for initiation of embryogenic suspensions: embryo clusters from gelled medium were briefly shaken in liquid medium and detached cells and embryogenic masses of 41–800 μm were used as inoculum. Maintenance of embryogenic suspensions was achieved using a low-density inoculum (43 mg l −1 ) by subculturing four embryogenic clumps of 0.8–1.2 mm per 70 ml of medium. Proliferation ability was maintained for almost 1 year through ten consecutive subcultures. The initiation and maintenance protocols first developed for a single genotype were effective when tested on 11 cork oak genotypes. Content Type Journal Article Category Original Paper Pages 1-11 DOI 10.1007/s00468-012-0763-y Authors Jesús Jiménez, Instituto Madrileño de Investigación y Desarrollo Rural, Agrario y Alimentario (IMIDRA), Finca El Encín, Apdo. 127, 28800 Alcalá de Henares, Madrid, Spain Dolores López-Vela, Instituto Madrileño de Investigación y Desarrollo Rural, Agrario y Alimentario (IMIDRA), Finca El Encín, Apdo. 127, 28800 Alcalá de Henares, Madrid, Spain Mar Ruiz-Galea, Instituto Madrileño de Investigación y Desarrollo Rural, Agrario y Alimentario (IMIDRA), Finca El Encín, Apdo. 127, 28800 Alcalá de Henares, Madrid, Spain Cristina Celestino, Instituto Madrileño de Investigación y Desarrollo Rural, Agrario y Alimentario (IMIDRA), Finca El Encín, Apdo. 127, 28800 Alcalá de Henares, Madrid, Spain Mariano Toribio, Instituto Madrileño de Investigación y Desarrollo Rural, Agrario y Alimentario (IMIDRA), Finca El Encín, Apdo. 127, 28800 Alcalá de Henares, Madrid, Spain Jesús Alegre, Instituto Madrileño de Investigación y Desarrollo Rural, Agrario y Alimentario (IMIDRA), Finca El Encín, Apdo. 127, 28800 Alcalá de Henares, Madrid, Spain Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    Reduction of crop yield from high water stress is a serious agricultural problem worldwide, which is expected to intensify under future global change scenarios. Efforts are underway worldwide to improve crops resistance to drought. One possible way is the careful choice of rootstock-scion combination. It is well known that water stress symptoms of grafted cherry trees to a large extent depend on the rootstock variety. Scions grafted on dwarf rootstocks show more serious stress symptoms, so it is reasonable to hypothesize that these symptoms and the tissue structure of the rootstock stem are connected. This paper examines this connection for 1-year-old seedlings of eight cherry rootstocks with different degree of vigor. Tissue structure was observed via scanning electron microscope images. Investigations were focused on number, size, and distribution of vessels, because they are principally responsible for water transport. Stem porosity (i.e., the total vessel area relative to the stem area, in cross-sectional view) of the dwarfing rootstocks was found to be significantly smaller than that of the others, supporting the notion that stem anatomical characteristics might contribute to water stress sensitivity. Content Type Journal Article Category Original Paper Pages 1-8 DOI 10.1007/s00468-012-0766-8 Authors Anikó Hajagos, Department of Fruit Science, Faculty of Horticultural Science, Corvinus University of Budapest, Villányi út 29-43, Budapest, 1118 Hungary György Végvári, Department of Fruit Science, Faculty of Horticultural Science, Corvinus University of Budapest, Villányi út 29-43, Budapest, 1118 Hungary Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    Citrus plants originate from southeastern Asia, in a large area with various climates characterized by a broad range of temperatures. Some species have been diversified in temperate climates, others in subtropical climates. Temperature is assumed to be a key factor in citrus species adaptation and diversification of basic cellular functions. In a field experiment, the tolerance of the three fundamental Citrus species C. medica L., C. reticulata Blanco and C. maxima (Burm.) Merr., and Fortunella japonica (Thunb.) Swing. to photooxidative stress caused by seasonal climatic changes was evaluated on adult trees by measuring net photosynthesis ( P net), stomatal conductance ( G s), maximum photosynthesis ( P max) and chlorophyll fluorescence ( F v/ F m). In addition, seasonal changes in oxidative status, antioxidant enzymes (superoxide dismutase, catalase, ascorbate peroxidase, monodehydroascorbate reductase, dehydroascorbate reductase and glutathione reductase) and antioxidant metabolites (ascorbate and glutathione) were monitored. Mandarin and pummelo appeared to be the most tolerant, showing the lowest down-regulation of photosynthetic parameters, and the lowest accumulation of oxidized compounds associated with efficiency of their antioxidant system. Kumquat showed intermediate behaviour, with a large diminution of photosynthetic parameters and marked accumulation of hydrogen peroxide, whereas the malondialdehyde content remained low, with a strong induction of glutathione synthesis. Finally, citron appeared to be the most sensitive genotype with a marked decrease in photosynthetic performance, the largest accumulation of oxidative parameters, insufficient induction of antioxidant enzymes and down-regulation of ascorbate and glutathione synthesis. Content Type Journal Article Category Original Paper Pages 1-13 DOI 10.1007/s00468-012-0769-5 Authors Jérémie Santini, UR 1103 Génétique et Ecophysiologie de la Qualité des Agrumes, INRA, 20230 San Giuliano, France Jean Giannettini, Laboratoire Biochimie and Biologie Moléculaire du Végétal, CNRS, UMR 6134 SPE, 20250 Corte, France Olivier Pailly, UR 1103 Génétique et Ecophysiologie de la Qualité des Agrumes, INRA, 20230 San Giuliano, France Stéphane Herbette, INRA, UMR 547 PIAF, 63100 Clermont-Ferrand, France Patrick Ollitrault, CIRAD, UPR 75, Avenue Agropolis, TA A-75/02, 34398 Montpellier cedex 5, France Liliane Berti, Laboratoire Biochimie and Biologie Moléculaire du Végétal, CNRS, UMR 6134 SPE, 20250 Corte, France François Luro, UR 1103 Génétique et Ecophysiologie de la Qualité des Agrumes, INRA, 20230 San Giuliano, France Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    Tree species use a variety of strategies to obtain resources. As a result, semi-deciduous forest species and cerrado species can grow in close proximity and in the same climate, while occupying very different vegetation types. The aim of this study was to understand the dynamic responses of Hymenaea courbaril, a forest species, and Hymenaea stigonocarpa, a cerrado species, to annual climatic variation and increasing atmospheric CO 2 concentrations under the same macroclimatic conditions. To that goal, we constructed chronologies of tree-ring width, vessel area, and intrinsic water-use efficiency (calculated from tree-ring δ 13 C content) for Hymenaea trees growing in a mosaic of the two vegetation types. Our analyses revealed that both species responded to climatic variation in similar ways, but with different intensities and at different times of year. Climate models showed that precipitation had a stronger effect on tree-ring width and earlywood vessel area of H. courbaril and temperature was slightly more determinant for H. stigonocarpa . In addition, both species showed increasing intrinsic water-use efficiency over the last five decades, but only individuals with reduced growth rate presented this trend, suggesting that those specimens in favorable growth conditions do not respond to the atmospheric CO 2 enrichment. Despite the trend in water-use efficiency found in some individuals, it did not reflect in a higher growth rate. The differences between the two species documented by us may be due to divergent sources of hydrological stress in the two vegetation types. Content Type Journal Article Category Original Paper Pages 1-12 DOI 10.1007/s00468-012-0764-x Authors Giuliano Maselli Locosselli, Departamento de Botânica, Instituto de Biociências, Universidade de São Paulo, Rua do Matão, 277, Butantã, CEP 09715-030 São Paulo, SP, Brazil Marcos Silveira Buckeridge, Departamento de Botânica, Instituto de Biociências, Universidade de São Paulo, Rua do Matão, 277, Butantã, CEP 09715-030 São Paulo, SP, Brazil Marcelo Zacharias Moreira, Centro de Energia Nuclear na Agricultura, Universidade de São Paulo, Avenida Centenário, 303, CEP 131416-000 Piracicaba, SP, Brazil Gregório Ceccantini, Departamento de Botânica, Instituto de Biociências, Universidade de São Paulo, Rua do Matão, 277, Butantã, CEP 09715-030 São Paulo, SP, Brazil Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    We applied dendroclimatological techniques to determine long-term stationarity of climate–growth relationships and recent growth trends of three widespread coniferous tree species of the central Austrian Alps, which grow intermixed at dry mesic sites within a dry inner Alpine environment (750 m asl). Time series of annual increments were developed from 〉120 mature trees of Picea abies , Larix decidua and Pinus sylvestris . Calculation of response functions for the period 1911–2009 revealed significant differences among species in response to climate variables. While precipitation in May–June favored radial growth of P. abies and L. decidua , P. sylvestris growth mainly depended on April–May precipitation. P. abies growth was most sensitive to May–June temperature (inverse relationship). Moving response function coefficients indicated increasing drought sensitivity of all species in recent decades, which is related to a decline in soil moisture availability due to increasing stand density and tree size and higher evapotranspiration rates in a warmer climate. While recent trend in basal area increment (BAI) of L. decidua distinctly declined implying high vulnerability to drought stress, moderately shade-tolerant P. abies showed steadily increasing BAI and quite constant BAI was maintained in drought-adapted P. sylvestris , although at the lowest level of all species. We conclude that synergistic effects of stand dynamics and climate warming increased drought sensitivity, which changed the competitive strength of co-occurring conifers due to differences in the inherent adaptive capacity. Content Type Journal Article Category Original Paper Pages 1-9 DOI 10.1007/s00468-012-0768-6 Authors Roman Schuster, Institute of Botany, Leopold-Franzens-University of Innsbruck, Sternwartestrasse 15, 6020 Innsbruck, Austria Walter Oberhuber, Institute of Botany, Leopold-Franzens-University of Innsbruck, Sternwartestrasse 15, 6020 Innsbruck, Austria Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung: Context   The reforestation of degraded tropical pastures requires innovative tree planting systems that consider land user needs. Aim   We established a silvopastoral reforestation system and assessed the effects of companion trees on the native timber tree Tabebuia rosea in Panama. Timber tree individuals were established in (1) solitary plantings (TSol) or in companion plantings with (2) Guazuma ulmifolia (TGua) or (3) the nitrogen-fixing Gliricidia sepium (TGli). Methods   We quantified growth characteristics and herbivory of T. rosea , and analyzed leaf chemistry (including the stable isotopes δ 15 N and δ 13 C) and structure (leaf mass per area). Results   Companion trees significantly affected stem diameter growth of T. rosea . Stem diameter growth was as high in TGli trees as in TSol trees but was reduced in TGua trees. Furthermore, TGua trees had higher leaf water content, and lower δ 13 C and lower leaf mass-to-area ratio than TGli trees, suggesting there were effects of shading by G. ulmifolia on T. rosea . Herbivory was high but not affected by planting regimes. Leafing phenology did not differ between planting regimes and G. sepium did not increase nitrogen content in T. rosea leaves. Conclusion   Companion tree planting can support timber tree growth in silvopastoral reforestations, but adequate species selection is crucial for successful implementation of this planting system. Tree–tree interactions seem to be more relevant for timber tree growth than herbivory in the studied system. Content Type Journal Article Category Original Paper Pages 1-12 DOI 10.1007/s13595-012-0239-7 Authors Judith Riedel, Institute of Agricultural Sciences, Applied Entomology, ETH Zurich, Schmelzbergstrasse 9/LFO, 8092 Zurich, Switzerland Silvia Dorn, Institute of Agricultural Sciences, Applied Entomology, ETH Zurich, Schmelzbergstrasse 9/LFO, 8092 Zurich, Switzerland Mirco Plath, Institute of Agricultural Sciences, Applied Entomology, ETH Zurich, Schmelzbergstrasse 9/LFO, 8092 Zurich, Switzerland Karsten Mody, Institute of Agricultural Sciences, Applied Entomology, ETH Zurich, Schmelzbergstrasse 9/LFO, 8092 Zurich, Switzerland Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560

Beschreibung: • Context   The transition of microfibril angle (MFA) values from juvenile to mature wood marks the change from variable, low-quality wood to stronger and more consistent wood that can produce higher value products. • Aims   We evaluate the utility of different statistical models that predict how much of a log is higher quality mature wood based on MFA. • Methods   MFA was measured from pith to bark at breast height in six lodgepole pine stands in western Canada. Six different forms of two-segment regression models were assessed to determine the point of transition (TP) in MFA from juvenile to mature wood. • Results   All six models provided useful and significant TP estimates. In the first segment (juvenile phase), the quadratic form produced the most conservative TPs, the linear form the least conservative, and the exponential form was intermediate. A linear second segment (mature phase) was only a minor improvement over a constant. There were significant differences in MFA TP among some sites. Analyses of the relationships between TP and tree variables, e.g., DBH, height, were inconclusive. • Conclusions   Any of the six two-segment models can be used objectively to estimate MFA transition points; the choice of model will allow mill managers to manage risk in product out-turn. Content Type Journal Article Category Original Paper Pages 1-11 DOI 10.1007/s13595-012-0226-z Authors Mingliang Wang, Warnell School of Forestry and Natural Resources, University of Georgia, Hinton, AB, Canada James D. Stewart, Canadian Wood Fibre Centre, Canadian Forest Service, Natural Resources Canada, 5320 122 Street, Edmonton, AB, Canada Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560

Beschreibung:    Stem diameter in Gallesia integrifolia (Spreng.) Harms (Phytolaccaceae) increases by forming concentric rings of xylem alternating with phloem, which show frequent anastomoses. After a period of primary growth and the formation of first (normal) ring of vascular cambium, further successive rings are initiated outside this cambium. The second ring of cambium originates from the pericycle parenchyma located between the proto-phloem, and the pericycle fibres. Each cambium produces centripetally secondary xylem and centrifugally secondary phloem. Differentiation of xylem precedes that of phloem and the first elements formed are always xylem fibres. Structurally, the vascular cylinder is composed by successive rings of secondary xylem and phloem. These rings are separated by wide bands of conjunctive parenchyma tissue. Presence of collateral vascular bundles with irregular orientation is observed in the region of anastomoses of two or more bands of conjunctive tissue. These bundles are surrounded by isodiametric, lignified and thick-walled cells. In some of the cambial rings, occurrence of polycentric rays was also noticed; these rays are tall, and characterized by the presence of meristematic regions that differentiated into thick-walled elements of secondary xylem. Origin and development of the successive cambia and the structure of xylem are discussed. Content Type Journal Article Category Original Paper Pages 1-8 DOI 10.1007/s00468-012-0762-z Authors Kishore S. Rajput, Department of Botany, Faculty of Science, The Maharaja Sayajirao University of Baroda, Vadodara, 390002 India Diego Romeiro, Instituto Florestal, CP 1322, Sao Paulo, CEP 02377-000 Brazil Eduardo L. Longui, Instituto Florestal, CP 1322, Sao Paulo, CEP 02377-000 Brazil Carmen R. Marcati, Departamento de Recursos Naturais, Faculdade de Ciências Agronômicas, Universidade Estadual Paulista, Campus de Botucatu, SP, CP 237, Sao Paulo, CEP 18603-970 Brazil Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    In the search of timber species being tolerant towards summer droughts, which are expected to be more frequent in future, Douglas-fir is often discussed as a potential alternative for spruce in Central Europe. To assess physiological and growth reactions of Douglas-fir provenances towards climate- and weather-related environmental conditions we took advantage of a provenance trial with three sites in south-western Germany located along an elevation gradient. We examined six different provenances of Douglas-fir from North America for oxygen (δ 18 O) and carbon (δ 13 C) stable isotope composition in tree rings as well as for radial increment for a 7 year period and long-term height growth. Our results show that different Douglas-fir provenances clearly vary in their drought sensitivity at the driest and warmest site in the valley as shown by the radial growth decline in the extreme dry and hot year 2003. The growth decline in the provenances Pamelia Creek, Cameron Lake, Duncan Paldi and Conrad Creek could be clearly attributed to a reduction in stomatal conductance as assessed by the relations between δ 18 O and δ 13 C in the tree rings. These responses were not related to the long-term average climate at the places of origin of the provenances and the provenances with the lowest long-term (height) growth potential were the ones least affected in radial increment by the extreme drought of 2003. When selecting suitable Douglas-fir provenances, which are adapted to the climatic conditions projected for the future we thus might need to take into account the trade-off between the adaptation to extreme drought periods and the long-term growth performance. Site-specific evaluations of the probability of extreme drought events are thus needed to select the appropriate provenances. Content Type Journal Article Category Original Paper Pages 1-16 DOI 10.1007/s00468-012-0765-9 Authors Kirstin Jansen, Institute for Landscape Biogeochemistry, Leibniz Centre for Agricultural Landscape Research (ZALF), Eberswalderstr. 84, 15374 Müncheberg, Germany Jakob Sohrt, Core Facility Metabolomics, Centre for Systems Biology (ZBSA), Albert-Ludwigs-University Freiburg, Habsburgerstr. 49, 79104 Freiburg, Germany Ulrich Kohnle, Forest Research Institute Baden-Württemberg (FVA), Wonnhaldestr. 4, 79100 Freiburg, Germany Ingo Ensminger, Forest Research Institute Baden-Württemberg (FVA), Wonnhaldestr. 4, 79100 Freiburg, Germany Arthur Gessler, Institute for Landscape Biogeochemistry, Leibniz Centre for Agricultural Landscape Research (ZALF), Eberswalderstr. 84, 15374 Müncheberg, Germany Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    Mangroves are mainly tropical tree species that occur on either side of the equator and because temperature decreases with increasing latitude, the latitudinal limits of mangroves are expected to be mainly controlled by temperature-related drivers. Here, we hypothesized that the mangrove genera ( Avicennia and Rhizophora ) have the same limiting temperature at all of their upper latitudinal limits at the global scale. We first derived six parameters from monthly mean sea surface temperature (SST) and air temperature (AT). Furthermore, we investigated whether the variation in these temperature parameters is related (i) to the position of the limit, (ii) to specific temperature requirements of congeneric species and/or (iii) to aridity. All temperature-based parameters derived from AT and SST are highly variable among the upper latitudinal limits of Avicennia and Rhizophora . Hence, we found no common isotherms to characterize the limits of the two mangrove genera, which contradict previous studies. The high temperature variation among limits can be due to partial range filling towards the latitudinal limits. This is supported by the higher warmest month temperatures at the latitudinal limits of the northern hemisphere as compared to the southern hemisphere. However, temperature parameters at limits, with no or less than 250 km of available poleward coast, are not different from other limits, and adult tree height at the limits is not correlated with the temperature-based variables. Mean air temperature is warmer at limits with an arid climate, suggesting mechanisms of compensation towards higher temperatures when Avicennia and Rhizophora have to cope with both aridity and low temperature. Content Type Journal Article Category Original Paper Pages 1-13 DOI 10.1007/s00468-012-0760-1 Authors Katrien Quisthoudt, Laboratory for Plant Biology and Nature Management, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium Nele Schmitz, Laboratory for Plant Biology and Nature Management, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium Christophe F. Randin, Institute of Botany, Universität Basel, Schönbeinstrasse 6, 4056 Basel, Switzerland Farid Dahdouh-Guebas, Laboratory for Plant Biology and Nature Management, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium Elisabeth M. R. Robert, Laboratory for Plant Biology and Nature Management, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium Nico Koedam, Laboratory for Plant Biology and Nature Management, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    We examined the growth and photosynthetic responses of Japanese forest tree species to sulfur dioxide (SO 2 ) under different nitrogen (N) loads to soil. We grew Quercus serrata , Fagus crenata , Castanopsis sieboldii , Larix kaempferi , Pinus densiflora, and Cryptomeria japonica seedlings in Andisol supplemented with N as NH 4 NO 3 solution at 0, 20, and 50 kg ha −1  year −1 . Seedlings were exposed daily to charcoal-filtered air or SO 2 at 10, 20, and 40 nl l −1 for two growing seasons. Except for C. japonica seedlings, exposure to SO 2 at a relatively low concentration stimulated whole-plant growth, especially under a relatively high N load. The effects of N load on the negative impact of SO 2 on whole-plant growth were synergistic in Q. serrata , F. crenata , C. sieboldii, and P. densiflora , counteractive in L. kaempferi , and additive in C. japonica . In Q. serrata , F. crenata , C. sieboldii, and P. densiflora seedlings, the different responses of whole-plant growth to SO 2 among the N treatments were because of the effect of N load on the response of the net photosynthetic rate to SO 2 . L. kaempferi seedlings showed N load-induced tolerance of whole-plant growth to SO 2 . This was explained by the effect of N load on the responses of photosynthesis and development of assimilative organs to SO 2 . The different growth responses to SO 2 among the N treatments were explained by the effects of N load on the SO 2 uptake rate (evaluated by stomatal diffusive conductance) or the accumulated SO 2 uptake (evaluated by foliar S concentration). Content Type Journal Article Category Original Paper Pages 1-16 DOI 10.1007/s00468-012-0755-y Authors Masahiro Yamaguchi, Faculty of Agriculture, Tokyo University of Agriculture and Technology, Fuchu, Tokyo 183-8509, Japan Makoto Watanabe, Research Faculty of Agriculture, Hokkaido University, Sapporo, Hokkaido 060-8589, Japan Chikako Tabe, Faculty of Agriculture, Tokyo University of Agriculture and Technology, Fuchu, Tokyo 183-8509, Japan Junichi Naba, Faculty of Agriculture, Tokyo University of Agriculture and Technology, Fuchu, Tokyo 183-8509, Japan Hideyuki Matsumura, Environmental Science Research Laboratory, Central Research Institute of Electric Power Industry, Abiko, Chiba 270-1194, Japan Yoshihisa Kohno, Environmental Science Research Laboratory, Central Research Institute of Electric Power Industry, Abiko, Chiba 270-1194, Japan Takeshi Izuta, Institute of Agriculture, Tokyo University of Agriculture and Technology, Fuchu, Tokyo 183-8509, Japan Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung: Context   Mediterranean pines share many common life-history traits. They are found at almost all altitudinal levels around the Mediterranean Basin, from sea level to high-elevation mountains, and from hot and dry to wet and cold bioclimates. Their distribution ranges from widespread to regional and narrow, and from dense extensive populations to small populations of scattered individuals. They have been extensively used by human civilizations for millennia. Aims   I show which are the main phylogenetic, ecological, and climatic factors explaining the patterns of within and among-population genetic diversity in Mediterranean pines. Methods   I use a narrative synthesis approach and multiple examples from the literature on pine species from the Mediterranean Basin and California. Results   While Mediterranean pines have the highest levels of differentiation worldwide, their genetic diversity increases from west to east and is significantly reduced in low-elevation species. Factors such as ancestral adaptation to wildfire, reduction of effective population size during the Last Glacial Maximum, long distance dispersal during the Holocene, and more recent adaptation to patchy environmental conditions could explain these patterns. Conclusion   Because of contrasted ecological, demographic, historical, and geographical processes, and despite their common biological attributes, pines of the Mediterranean Basin display complex biogeographic patterns at neutral gene level that can help retrace their evolutionary history. Although individual species often represent unique case studies that make generalizations risky, locating habitats of significantly high and low genetic diversity is key for detecting and understanding the major factors affecting gene diversity and may prove useful for profiling areas of high conservation value in the Mediterranean. Content Type Journal Article Category Review Paper Pages 1-8 DOI 10.1007/s13595-012-0219-y Authors Bruno Fady, INRA, UR629, Ecologie des Forêts Méditerranéennes (URFM), Domaine St Paul, site Agroparc, 84914 Avignon, France Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560

Beschreibung:    In the National Natural Reserve of the Qilian Mountains, northwest China, automated dendrometers were installed on Qilian juniper ( Sabina przewalskii Kom.) in 2010. Here, we present a complete 1-year data series of dendrometer measurements and synchronous meteorological records. The mean daily radius change index curve obtained by first-difference standardization was analyzed. The results indicate strong similarities of stem radius variations among the studied trees. By graphical inspection of sub-diurnal shrinkage and expansion patterns, seasonal stem radius variations could be divided into two general phases. During early winter to spring, daily amplitudes show strong fluctuations, and meteorological data indicate that both air and soil temperatures are positively related to stem radius swelling. From late March to early November 2011, stem radius expansion is negatively related to both air and soil temperatures, as well as to vapor pressure deficit, and positively related to precipitation and soil moisture. We found that the dividing lines between the two phases were strongly linked to the occurrence of a 0 °C daily mean air temperature, indicating that air temperature played an important effect on stem radius variations in this cold and arid environment. During the growing season in 2011, May and June are the most productive months. Content Type Journal Article Category Original Paper Pages 1-11 DOI 10.1007/s00468-012-0743-2 Authors Zhangyong Wang, Key Laboratory of Desert and Desertification, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, 320 Donggang West Road, Lanzhou, 730000 China Bao Yang, Key Laboratory of Desert and Desertification, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, 320 Donggang West Road, Lanzhou, 730000 China Annie Deslauriers, Département des Sciences Fondamentales, Université du québec à Chicoutimi, 555 boul. de l’Université, Chicoutimi, QC G7H 2B1, Canada Chun Qin, Key Laboratory of Desert and Desertification, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, 320 Donggang West Road, Lanzhou, 730000 China Minhui He, Key Laboratory of Desert and Desertification, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, 320 Donggang West Road, Lanzhou, 730000 China Feng Shi, Key Laboratory of Desert and Desertification, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, 320 Donggang West Road, Lanzhou, 730000 China Jingjing Liu, Key Laboratory of Desert and Desertification, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, 320 Donggang West Road, Lanzhou, 730000 China Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    The use of in vitro regenerated plants in forestry and orchard depends ultimately on the development of efficient transplantation protocols, ensuring high survival rates and successful establishment under field conditions. We tested the performance of micropropagated carob trees ( Ceratonia siliqua L.) throughout the acclimatization process in terms of survival, growth and physiological traits, including field comparisons with seed-derived and mother plants. The field trial was 100 % successful, i.e. we found no major differences between micropropagated, seed-derived and mother plants in terms of growth rate, height, number of leaves, photosynthetic efficiency, chlorophyll fluorescence, chlorophyll content and soluble protein content, although these parameters changed significantly during acclimatization. Stomatal conductance ( g s ) was reduced by fourfold when plants were transferred from in vitro culture to the growth chamber, thus preventing uncontrolled wilting. The photosynthetic rate ( P N ) was relatively low in vitro, in the growth chamber and the greenhouse, but increased to match seed-derived and mother plants in the field. The chlorophyll a / b ratio in leaves from in vitro and growth chamber plants was typical of shade plants (2.1) but became more characteristic of sun plants in the subsequent acclimatization stages (3.1–3.5). The maximum efficiency of photosystem II ( F v / F m ) remained mostly constant at ~0.80 throughout acclimatization, as is typical for healthy, non-stressed plants. We conclude that our micropropagation and acclimatization protocols provide a suitable alternative to traditional mass propagation techniques for the carob tree. Content Type Journal Article Category Original Paper Pages 1-10 DOI 10.1007/s00468-012-0753-0 Authors M. L. Osório, Institute for Biotechnology and Bioengineering, Centre of Genomics and Biotechnology (IBB-CGB), Faculty of Sciences and Technology, Ed. 8, University of Algarve, Campus de Gambelas, 8005-139 Faro, Portugal J. Osório, Institute of Mediterranean Agricultural and Environmental Sciences (ICAAM), Faculty of Sciences and Technology, Ed. 8, University of Algarve, Campus de Gambelas, 8005-139 Faro, Portugal S. Gonçalves, Institute for Biotechnology and Bioengineering, Centre of Genomics and Biotechnology (IBB-CGB), Faculty of Sciences and Technology, Ed. 8, University of Algarve, Campus de Gambelas, 8005-139 Faro, Portugal M. M. David, Institute of Mediterranean Agricultural and Environmental Sciences (ICAAM), Faculty of Sciences and Technology, Ed. 8, University of Algarve, Campus de Gambelas, 8005-139 Faro, Portugal M. J. Correia, Centro de Estudos em Ciências e Tecnologias Agrárias (CECTC), Faculty of Sciences and Technology, Ed. 8, University of Algarve, Campus de Gambelas, 8005-139 Faro, Portugal A. Romano, Institute for Biotechnology and Bioengineering, Centre of Genomics and Biotechnology (IBB-CGB), Faculty of Sciences and Technology, Ed. 8, University of Algarve, Campus de Gambelas, 8005-139 Faro, Portugal Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    Interactions between photosynthetic rate, transpiration, content of soluble carbohydrates, leaf dimensions and structural parameters and growth of hybrid aspen ( Populus tremula  ×  P. tremuloides Michx.) were studied in relation to soil pH and chemical composition. The investigations were conducted in two plantations on former agricultural lands in North Estonia. One plantation was established on a territory influenced for a long time by alkaline cement dust pollution before plantation establishment and the other on an unpolluted territory. At pH 7.4 and higher concentrations of Ca, K, Mg, N and P in soil on the polluted area inhibition of height growth and diameter at breast height, leaf area and dry mass was observed compared to the unpolluted plantation with an optimum soil pH of 6.7. Differences in hybrid aspen leaves in the two plantations were related to the lower net photosynthetic and transpiration rates and higher starch and sucrose contents in the polluted plantation. Leaves from alkaline soil had a thicker palisade mesophyll layer and lower number of stomata at abaxial epidermis. The relatively low N concentration in leaves in the polluted area was associated with the low height and diameter at breast height of trees. Content Type Journal Article Category Original Paper Pages 1-12 DOI 10.1007/s00468-012-0754-z Authors Malle Mandre, Department of Ecophysiology, Institute of Forestry and Rural Engineering, Estonian University of Life Sciences, Viljandi mnt 18B, 11216 Tallinn, Estonia Jaan Klõšeiko, Department of Ecophysiology, Institute of Forestry and Rural Engineering, Estonian University of Life Sciences, Viljandi mnt 18B, 11216 Tallinn, Estonia Aljona Lukjanova, Department of Ecophysiology, Institute of Forestry and Rural Engineering, Estonian University of Life Sciences, Viljandi mnt 18B, 11216 Tallinn, Estonia Arvo Tullus, Department of Silviculture, Institute of Forestry and Rural Engineering, Estonian University of Life Sciences, Kreutzwaldi 5, 51014 Tartu, Estonia Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    Previously, we found that secretory cell degradation typically occurred through programmed cell death during secretory cavity development in Citrus sinensis L. (Osbeck). This finding indicated that secretory cavities could be utilized as a new cell biology model for investigating the regulatory mechanisms of plant programmed cell death. To study further the programmed cell death during secretory cavity development in Citrus fruit, we studied the morphogenetic characteristics of secretory cavities during their development in Citrus grandis cv. Tomentosa. Using light microscope- and electron microscope-TUNEL assays, immunohistochemistry and immunocytochemistry, we described the precise spatial and temporal alterations in caspase 3-like distribution, chromatin condensation and DNA fragmentation during the programmed cell death of secretory cavity cells. Caspase 3-like was found to be significantly located in both the cytoplasm and the nucleus of secretory cavity cells undergoing programmed cell death, and caspase 3-like is closely associated with chromatin condensation and DNA fragmentation. Interestingly, both caspase 3-like and DNA fragmentation were detected in the nucleoli. Our findings suggest that caspase 3-like may be involved in the programmed cell death of secretory cavity cells, especially in chromatin condensation, DNA fragmentation, nuclear degradation and the degradation of certain organelles. Content Type Journal Article Category Original Paper Pages 1-15 DOI 10.1007/s00468-012-0752-1 Authors Peiwei Liu, Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm, South China Agricultural University, 510642 Guangzhou, China Shejian Liang, Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm, South China Agricultural University, 510642 Guangzhou, China Nan Yao, Guangdong Key Laboratory of Plant Resources, State Key Laboratory of Biocontrol, Sun Yat-sen University, 510006 Guangzhou, China Hong Wu, Guangdong Key Laboratory for Innovative Development and Utilization of Forest Plant Germplasm, South China Agricultural University, 510642 Guangzhou, China Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    Short- and long-term growth responses to drought and climatic influences still remain poorly understood. In this study, we investigated the impact of climatic drivers (temperature, precipitation) and drought, using the Standardized Precipitation Index (SPI) calculated at different time scales (1–48 months), on earlywood (EW) and latewood (LW) widths in Pinus halepensis. Nine forests subjected to dry summer conditions were sampled in Mediterranean semi-arid areas from north-eastern Spain. In addition, we explored the seasonal dynamics of cambial activity and wood formation in relation to short-term climate variability. We found two peaks of tracheid cell production corresponding to EW (May – June) and LW (mid-July–August) growth phases, associated with a sharp decrease in enlarging cells in early July in response to low water availability. In the period of analysis (1970–2005), EW growth was positively correlated with precipitation in previous December and current January, April, May and June, while it was negatively correlated with temperature in June and July. LW was correlated positively with minimum temperatures in January. Probably this was an indirect relationship as a consequence of increased EW width at higher January temperatures. Drought affected more negatively EW than LW formation as evidenced the higher SPI-EW correlation ( r  = 0.72) than the SPI-LW one ( r  = 0.54). The strongest EW response to drought was observed in July, whereas the highest LW response to drought occurred in September; and this seasonal pattern matched the phases of lowest EW and LW tracheid production. Under a future reduction of winter and spring precipitation, the studied forests may show a decrease in tracheid cell production, causing a decline of radial growth, a reduction in hydraulic conductivity and, indirectly, a hampered carbon uptake in such semi-arid woodlands. Content Type Journal Article Category Original Paper Pages 1-12 DOI 10.1007/s00468-012-0756-x Authors Edmond Pasho, Faculty of Forestry Sciences, Agricultural University of Tirana, 1029, Kodër-Kamëz, Tirana, Albania J. Julio Camarero, ARAID-Instituto Pirenaico de Ecología (CSIC), Avda. Montañana 1005, Zaragoza, 50080 Spain Sergio M. Vicente-Serrano, Instituto Pirenaico de Ecología (CSIC), Avda. Montañana 1005, Zaragoza, 50080 Spain Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    Genetic variability and population structure of Sapindus trifoliatus L. (Sapindaceae), collected from Gujarat, Karnataka and Uttar Pradesh states were estimated using three DNA fingerprinting methods viz., random amplified polymorphic DNA (RAPD), directed amplification of minisatellite DNA (DAMD) and inter-simple sequence repeats (ISSR). The cumulative data analysis carried out for all three markers showed 69.42 % polymorphism. The intra-population genetic diversity analysis revealed the highest values of Nei’s genetic diversity (0.16), Shannon information index (0.24) and polymorphic loci (43.99 %) among Bhavnagar (BH) population, whereas lowest values were found in Junagarh (JU) population. The maximum inter-population average genetic distance (0.20) was between Allahabad (AL) and JU populations. Analysis of molecular variance (AMOVA) showed highest percentage of variation among individuals of populations (56 %) followed by 25 % among populations and 19 % among regions. Principal coordinate analysis and UPGMA dendrogram revealed that genetic diversity was in congruence with the geographical diversity. The data strongly suggest that low genetic flow, geographic isolation and to some extent genetic drift are the major factors responsible for high genetic differentiation. Preservation of genetic diversity of S. trifoliatus is important, both to promote adaptability of the populations to changing environment as well as to preserve a large gene pool for future genetic improvement. The present study using RAPD, DAMD and ISSR profiles of S. trifoliatus provide the means of rapid characterization of accessions within the populations, and thus enable the selection of appropriate accessions for further utilization in conservation and prospection programs of this important plant genetic resource. Content Type Journal Article Category Original Paper Pages 1-12 DOI 10.1007/s00468-012-0770-z Authors Kamalesh Singh Mahar, Molecular Systematics, CSIR-National Botanical Research Institute, Rana Pratap Marg, Lucknow, 226 001 Uttar Pradesh, India Tikam Singh Rana, Molecular Systematics, CSIR-National Botanical Research Institute, Rana Pratap Marg, Lucknow, 226 001 Uttar Pradesh, India Shirish Anand Ranade, Plant Molecular Biology (Genomics) Laboratory, CSIR-National Botanical Research Institute, Rana Pratap Marg, Lucknow, 226 001 Uttar Pradesh, India Veena Pande, Department of Biotechnology, Kumaun University, Bhimtal, Nainital, 263 136 Uttarakhand, India Lok Man Singh Palni, G. B. Pant Institute of Himalayan Environment and Development, Kosi-Katarmal, Almora, 263 643 Uttarakhand, India Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    Scientists have discussed the halophytic nature of intertidal plants for decades, and have generally suggested that inherent differentiation of an obligate halophyte from a facultative halophyte relates strongly to whether the plant can survive in fresh water, and not much else. In this mini-review, we provide additional insight to support the pervasive notion that mangroves as a group are truly facultative halophytes, and thus add discourse to the alternate view that mangroves have an obligate salinity requirement. Indeed, growth and physiological optima are realized at moderate salinity concentrations in mangroves, but we maintain the notion that current evidence suggests that survival is not dependent upon a physiological requirement for salt. Content Type Journal Article Category Review Pages 1-5 DOI 10.1007/s00468-012-0767-7 Authors Ken W. Krauss, US Geological Survey, National Wetlands Research Center, 700 Cajundome Blvd, Lafayette, LA 70506, USA Marilyn C. Ball, Division of Plant Sciences, Research School of Biology, College of Medicine, Biology and Environment, Australian National University, The RN Robertson Bldg. (#46), Biology Place, Canberra, ACT 0200, Australia Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung: • Context   The Mediterranean Basin is a fire-prone area. Pinus halepensis Mill. is a naturally growing conifer which is frequently used for reforestation and restoration as it displays some degree of adaption to fire. One of the traits conferring tolerance to fire is the frequent presence of serotinous cones that are thought to protect seeds from fire damage. • Aim   We checked for the physiological responses of seeds to different intensities of fire and related them to the degree of serotiny of the cones. • Methods   Germination percentage, mean germination rate and enzymatic activity (α-amylase and protease) were recorded for seeds burned either free or enclosed in cones. We included as experimental factors the following: fire intensity, serotiny and time during which seeds were stored in cones after harvesting and germination stage. • Results   Burned seeds (released and enclosed) developed in serotinous cones exhibited higher heat insulation. In released seeds, germination was decreasing according to increasing fire intensity, although we found differences depending on site, serotiny and time stored after harvesting. The enzymatic activity was also found to be related to serotiny and fire intensity. • Conclusion   Serotiny is an adaptive trait increasing the tolerance to fire which should be promoted in natural and restored populations. Content Type Journal Article Category Original Paper Pages 1-11 DOI 10.1007/s13595-012-0236-x Authors Daniel Moya, Escuela Técnica Superior de Ingenieros Agrónomos de Albacete, Universidad de Castilla-La Mancha, Campus Universitario s/n, 02071 Albacete, Spain Jorge De las Heras, Escuela Técnica Superior de Ingenieros Agrónomos de Albacete, Universidad de Castilla-La Mancha, Campus Universitario s/n, 02071 Albacete, Spain Rossella Salvatore, Facoltá di Agraria, Università della Basilicata, via Ateneo Lucano 10, I-85100 Potenza, Italy Edelmira Valero, Escuela Técnica Superior de Ingenieros Industriales de Albacete, Universidad de Castilla-La Mancha, Campus Universitario s/n, 02071 Albacete, Spain Vittorio Leone, Facoltá di Agraria, Università della Basilicata, via Ateneo Lucano 10, I-85100 Potenza, Italy Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560

Beschreibung: • Context   The Salzmann pine ( Pinus nigra ssp. salzmannii ) is an endemic subspecies of black pine native to the Western Mediterranean basin. In Spain, Salzmann pine covers extensive areas (approx. 350 000 ha), while in France where few scattered populations subsist, its distribution area is estimated at approx. 3 000 ha. • Method   We used a dendroecological approach to understand the impact of climate fluctuations on Salzmann pine from France. Spatial and temporal variability of radial growth response was compared in three ecologically different populations (Conflent, Gorges du Tarn, Saint-Guilhem-le-Désert). • Results   The Conflent population showed a strong sensitivity to spring precipitation deficits (March to June), while at Gorges du Tarn and Saint-Guilhem sites, autumn (October) of the previous year and winter (February) temperatures explained more variance than precipitations and were, respectively, negatively and positively correlated to radial growth. • Conclusion   Although covering a limited distribution range in France, Salzmann pine demonstrated large differences in radial growth response to climate and soil variations. Content Type Journal Article Category Original Paper Pages 1-7 DOI 10.1007/s13595-012-0237-9 Authors Thomas Amodei, Institut Méditerranéen de Biodiversité et d’Ecologie (IMBE), UMR CNRS 6116, Aix-Marseille Université, Europôle méditerranéen de l’Arbois, Pavillon Villemin, BP 80, 13 545 Aix en Provence Cedex 4, France Frédéric Guibal, Institut Méditerranéen de Biodiversité et d’Ecologie (IMBE), UMR CNRS 6116, Aix-Marseille Université, Europôle méditerranéen de l’Arbois, Pavillon Villemin, BP 80, 13 545 Aix en Provence Cedex 4, France Bruno Fady, INRA, UR629, Ecologie des Forêts Méditerranéennes(URFM), Domaine Saint-Paul, 84 914 Avignon Cedex 9, France Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560

Beschreibung: • Context    The rising demand of energy wood for heating purposes in Germany leads to concerns regarding the overexploitation of forests. A major aspect is the impact of whole-tree harvesting on long-term productivity of forest soils. • Aims    This study aimed to analyze the effects of nutrient removal on productivity using the historically prevalent practice of litter raking. Since there is a lack of controlled whole-tree harvesting experiments in Germany, we used litter raking as a surrogate management practice entailing the removal of nutrients from forest stands. • Methods    We used three sites with documented litter raking to analyze the effects of nutrient removal on productivity using dendroecological methods: two recent litter removal experiments in two Scots pine stands (Siegenburg and Burglengenfeld) and one oak stand (Eichhall) with documented historic litter raking. Basal area increment (BAI) and tree-ring characteristics were compared between periods with litter raking and the preceding periods for both treatment and control plots. • Results    For the two Scots pine sites with a relatively short litter raking period, no effects of litter raking on BAI could be ascribed to nutrient removal. On the oak site with a longer history of litter utilization, the loss in BAI due to litter raking amounts to 22 % during the period with active raking and to still 17 % in the recovery period. • Conclusions    These results contribute to the still very limited understanding about the impact of whole-tree harvesting on forest productivity in Germany by laying down an upper limit of possible effects due to nutrient removal, as nutrient loss by litter raking tends to be higher than nutrient loss by whole-tree harvesting. Content Type Journal Article Category Original Paper Pages 1-7 DOI 10.1007/s13595-012-0238-8 Authors Christian Zang, Chair of Ecoclimatology, Technische Universität München, Hans-Carl-von-Carlowitz-Platz 2, 85354 Freising, Germany Andreas Rothe, Faculty of Forestry, University of Applied Sciences Weihenstephan-Triesdorf, Hans-Carl-von-Carlowitz-Platz 3, 85354 Freising, Germany Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560

Beschreibung: • Context   Harsh environmental conditions in xeric sites of Andean Patagonia, affect the emergence, survival, and growth of either naturally grown or planted Austrocedrus seedlings. • Aims   We evaluated the effects of nurse shrubs and tree shelters on the survival and growth of Austrocedrus seedlings as compared to unprotected (control) areas and how differently produced seedling types perform under these treatments. • Methods   In 2006, two Austrocedrus seedling types (1 + 2 = S1 and Plug 2 + 1 = S2) were planted under shrub cover (C1), tree shelter (C2), and control (C3). Soil surface temperature and moisture were measured for each treatment during the first growing season, while seedling survival and height were recorded during 5 years. • Results   Survival was not affected by cover type the first year, but it was affected by seedling type (S1 〉 S2). After an extremely dry second growing season, seedling survival significantly decreased in relation to either cover or seedling type. Five years after plantation, survival was significantly higher for C1 and C2 (40–60 %) as compared to C3-S2 (18 %). Seedling height was significantly affected by cover, but not by seedling type. • Conclusions   The use of nurse shrubs and/or tree shelters is useful in Austrocedrus seedling restoration trials. Seedling morphology appears as relevant for survival in semiarid environments. Content Type Journal Article Category Original Paper Pages 1-10 DOI 10.1007/s13595-012-0234-z Authors María Florencia Urretavizcaya, Área de Conservación y Manejo de Bosques, Centro de Investigación y Extensión Forestal Andino Patagónico (CIEFAPCONICET) and Universidad Nacional de la Patagonia, San Juan Bosco, Sede Esquel, Ruta 259, C.C. 14-(9200), Esquel, Chubut, Argentina Guillermo E. Defossé, Área de Conservación y Manejo de Bosques, Centro de Investigación y Extensión Forestal Andino Patagónico (CIEFAPCONICET) and Universidad Nacional de la Patagonia, San Juan Bosco, Sede Esquel, Ruta 259, C.C. 14-(9200), Esquel, Chubut, Argentina Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560

Beschreibung:    Research related to the allometric relationships of tree height and projected tree crown area to diameter at breast height was conducted to look at the biological suitability and timber production potential of Douglas fir under the conditions present in central Europe. The dependence of allometric relationships on soil nutrient conditions were described in forest stands of Douglas fir and Norway spruce. The studied sites were climatically similar but differed in soil nutrient availability. A significant difference was found in the allometric relationships of Norway spruce trees from the nutrient poor and nutrient rich site. In contrast to the Norway spruce, there was no significant effect of site fertility on allometric relationships for Douglas fir suggesting that its allocation patterns were less sensitive to site nutrient conditions. Stem growth increment, which was measured weekly during two consecutive seasons for both species, was related to the weather conditions and available soil moisture. Stem growth of Douglas fir began about 2 weeks earlier than in the Norway spruce at both sites. At the nutrient rich site, most of the stem growth of both species occurred at the beginning of the season, while growth at the other site was more evenly distributed throughout the season. Data obtained in this study will be useful for modeling stem growth and analysis of water use efficiency of these two tree species. Content Type Journal Article Category Original Paper Pages 1-14 DOI 10.1007/s00468-012-0771-y Authors Josef Urban, Faculty of Forestry and Wood Technology, Mendel University in Brno, Zemědělská 3, Brno, 613 00 Czech Republic Kateřina Holušová, Faculty of Forestry and Wood Technology, Mendel University in Brno, Zemědělská 3, Brno, 613 00 Czech Republic Ladislav Menšík, Faculty of Forestry and Wood Technology, Mendel University in Brno, Zemědělská 3, Brno, 613 00 Czech Republic Jan Čermák, Faculty of Forestry and Wood Technology, Mendel University in Brno, Zemědělská 3, Brno, 613 00 Czech Republic Petr Kantor, Faculty of Forestry and Wood Technology, Mendel University in Brno, Zemědělská 3, Brno, 613 00 Czech Republic Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung: Context   For Central Europe, climate projections foresee an increase in temperature combined with decreasing summer precipitation, resulting in drier conditions during the growing season. This might negatively affect forest growth, especially at sites that are already water-limited, i.e., at low elevation. At higher altitudes trees might profit from increasing temperatures. Aims   We analyzed variations in radial growth of silver fir ( Abies alba Mill.) and Norway spruce ( Picea abies (L.) Karst.) along an altitudinal gradient from 400 until 1,140 m a.s.l. in the Black Forest, to assess climate responses with increasing elevation. Methods   Climate–growth relationships were analyzed retrospectively using tree-ring and climate data. In total, we sampled stem discs of 135 trees to build 27 species- and site-specific chronologies ( n fir  = 13, n spruce  = 14). Results   Our results indicate distinct differences in climate–growth relations between fir and spruce along the gradient. Growth of high-altitude fir was positively related to temperature from January till March. Growth of low-altitude fir and spruce at all elevations was positively related to precipitation and negatively to temperature during the growing season, particularly in July. A self-calibrating Palmer drought severity index underlined summer drought sensitivity of these trees. Conclusion   Overall, we found that climatic control of tree growth changes over altitude for fir. For spruce, a remarkable synchrony in growth variation and climate response was shown, which indicates that this species is drought sensitive at all studied elevations. In a future warmer climate, the growth of low-altitude fir and spruce along the entire studied gradient may be negatively affected in the Black Forest, if an increased evaporative demand cannot be compensated by increased water supply. Content Type Journal Article Category Original Paper Pages 1-9 DOI 10.1007/s13595-012-0241-0 Authors Marieke van der Maaten-Theunissen, Institute for Forest Growth, Albert-Ludwigs-University Freiburg, Tennenbacher Str. 4, 79106 Freiburg, Germany Hans-Peter Kahle, Institute for Forest Growth, Albert-Ludwigs-University Freiburg, Tennenbacher Str. 4, 79106 Freiburg, Germany Ernst van der Maaten, Institute for Forest Growth, Albert-Ludwigs-University Freiburg, Tennenbacher Str. 4, 79106 Freiburg, Germany Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560

Beschreibung: • Introduction   In the context of global environmental changes, better understanding of tree response to soil drought in young mixed species stands is needed to anticipate forest adaptation and management practices for the future. • Materials and methods   We investigated the functional response of five co-occurring broad-leaved tree species growing in a 15- to 25-year-old mixed stand in northeastern France during the 2006 summer drought. We measured functional traits related to water acquisition (phenology, rooting pattern and vulnerability of xylem to cavitation) and the ecophysiological response (sap flux density, leaf water potential) of these species to soil water shortage. • Results   Our study highlights contrasted drought response strategies among these species and a trade-off between leaf phenology, resistance of xylem to cavitation and root system depth. • Conclusion   At this site, a deep root system seemed to be a key functional trait for the species to cope with drought. Quercus robur and Salix capreae can be characterised as drought-avoidance species as they possess a deep root system and therefore did not strongly experience soil drought. Despite deep rooting capacity, Betula pendula did not really avoid soil drought and strongly regulated transpiration during dry periods. Nevertheless, the earliness of budburst of this species contributes to high annual growth rate. In contrast, Carpinus betulus and Fagus sylvatica both displayed typical characteristics of drought-sensitive species. Content Type Journal Article Category Original Paper Pages 1-9 DOI 10.1007/s13595-012-0233-0 Authors Marion Zapater, INRA, UMR 1137 INRA—Université de Lorraine, Forest Ecology and Ecophysiology, 54280 Champenoux, France Nathalie Bréda, INRA, UMR 1137 INRA—Université de Lorraine, Forest Ecology and Ecophysiology, 54280 Champenoux, France Damien Bonal, INRA, UMR 1137 INRA—Université de Lorraine, Forest Ecology and Ecophysiology, 54280 Champenoux, France Sylvia Pardonnet, INRA, UMR 1137 INRA—Université de Lorraine, Forest Ecology and Ecophysiology, 54280 Champenoux, France André Granier, INRA, UMR 1137 INRA—Université de Lorraine, Forest Ecology and Ecophysiology, 54280 Champenoux, France Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560

Beschreibung: Context   European beech ( Fagus sylvatica L.) is considered threatened by anticipated climate change, but the physiological causes of potential beech decline or mortality remains poorly understood. Aims   The purpose of the present study was to fuel debate about the assumption that carbohydrate depletion is involved in the decline of mature European beech. Methods   The health status of beech trees from a severely declining stand was visually assessed by examining their crown condition. Content and radial distribution of non-structural carbohydrates (starch and soluble carbohydrate) were analyzed in the trunks and compared to those reported earlier in trunks of healthy beech trees. Results and discussion   The distribution of carbohydrate in the beech trunks recorded here seemed affected by decline. We found a stronger radial decrease of starch content than those reported earlier for healthy beech trees. Carbohydrate reserves appear partially maintained in the outermost rings while starch depletion occurred in older wood rings in declining trees that may be able to mobilize carbohydrate reserves from older wood rings in response to successive climatic constraints. Content Type Journal Article Category Original Paper Pages 1-8 DOI 10.1007/s13595-012-0240-1 Authors Bastien Gérard, INRA, UMR 1137 Ecologie et Ecophysiologie Forestières, 54280 Champenoux, France Nathalie Bréda, INRA, UMR 1137 Ecologie et Ecophysiologie Forestières, 54280 Champenoux, France Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560

Beschreibung: Erratum to: Real time qPCR expression analysis of some stress related genes in leaf tissue of Pyrus communis cv. Conférence after infection with Erwinia amylovora Content Type Journal Article Category Erratum Pages 1-2 DOI 10.1007/s00468-012-0751-2 Authors K. Vrancken, Molecular and Physical Plant Physiology, Hasselt University, Agoralaan Building D, 3590 Diepenbeek, Belgium H. Schoofs, Pomology Department, PC Fruit Research Station, Fruittuinweg 1, 3800 Sint-Truiden, Belgium T. Deckers, Pomology Department, PC Fruit Research Station, Fruittuinweg 1, 3800 Sint-Truiden, Belgium R. Valcke, Molecular and Physical Plant Physiology, Hasselt University, Agoralaan Building D, 3590 Diepenbeek, Belgium Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    Pinus massoniana Lamb., a widely distributed coniferous species, is of ecologically and economically high value in southern China. However, it suffers serious damage from acid rain in recent decades. In order to gain a better understanding of the responses of P. massoniana to acid rain at the proteome level, a comparative proteomic study combined with physiological analyses between control and acid rain treatment was conducted. Among the over 1,000 protein spots detected reproducibly on the gel, we successfully identified 41 differentially expressed proteins, including 20 acid rain down-regulated proteins and 21 up-regulated proteins. The identified proteins were classified into five functional categories according to their biological functions. Among them, the photosynthesis and amino acid metabolism related proteins were greatly down-regulated, indicating the serious damages caused by acid rain in P. massoniana . By contrast, some energy- and defense-related proteins were dramatically up-regulated under acid rain, including proteins involved in tricarboxylic acid cycle (TCA), protein stability as well as those related to antioxidant system, suggesting that a variety of metabolic pathways were affected by acid rain. In particular, the expression of several proteins involved in secondary metabolism was also increased under acid rain stress, implying that the activated secondary metabolism plays an important role in the response of P. massoniana to acid rain. Content Type Journal Article Category Original Paper Pages 1-11 DOI 10.1007/s00468-012-0750-3 Authors Ting-Wu Liu, Key Laboratory for Coastal and Wetland Ecosystem of Ministry of Education, College of the Environment and Ecology, Xiamen University, Xiamen, 361005 Fujian, People’s Republic of China Wen-Jun Hu, Key Laboratory for Coastal and Wetland Ecosystem of Ministry of Education, College of the Environment and Ecology, Xiamen University, Xiamen, 361005 Fujian, People’s Republic of China Xiao-Qin Wang, Key Laboratory for Coastal and Wetland Ecosystem of Ministry of Education, College of the Environment and Ecology, Xiamen University, Xiamen, 361005 Fujian, People’s Republic of China Li Niu, Key Laboratory for Coastal and Wetland Ecosystem of Ministry of Education, College of the Environment and Ecology, Xiamen University, Xiamen, 361005 Fujian, People’s Republic of China Bin Fu, Key Laboratory for Coastal and Wetland Ecosystem of Ministry of Education, College of the Environment and Ecology, Xiamen University, Xiamen, 361005 Fujian, People’s Republic of China Fei-Hua Wu, Key Laboratory for Coastal and Wetland Ecosystem of Ministry of Education, College of the Environment and Ecology, Xiamen University, Xiamen, 361005 Fujian, People’s Republic of China Zhen-Ming Pei, Department of Biology, Duke University, Durham, NC 27708, USA Hai-Lei Zheng, Key Laboratory for Coastal and Wetland Ecosystem of Ministry of Education, College of the Environment and Ecology, Xiamen University, Xiamen, 361005 Fujian, People’s Republic of China Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    Eucalyptus polybractea R.T. Baker is the key species used in Australia to produce commercial quantities of pharmaceutical-grade eucalyptus oil. Much of the variability in oil yield observed in coppiced stands of the species is considered genetically determined. Nonetheless it is not known how genetics acts on leaf and secretory cavity morphology to influence oil yield. To examine this, we first chose similar-sized mature leaves of different genotypes and determined that secretory cavity size accounted for 84 % of the variation in oil yield between genotypes. We then examined natural variation in mature leaf size found along branches and observed oil yield to increase in a linear, but non-proportional fashion with increasing leaf size, suggesting leaves of different final sizes on a given tree can have different volumetric oil proportions. From these analyses, we calculated that a minimum of 2.2 μl of photosynthetic tissue is required to service each additional μl of secretory cavities as leaves expand. This suggests there is likely to be a maximum oil concentration obtainable in E. polybractea leaves for a given leaf size increase. Such information helps to understand the factors that underlie oil yields and provides a potential framework for selection strategies aimed at maximising harvestable oil yields. Content Type Journal Article Category Short Communication Pages 1-6 DOI 10.1007/s00468-012-0744-1 Authors Jason Q. D. Goodger, School of Botany, The University of Melbourne, Parkville, VIC 3010, Australia Ian E. Woodrow, School of Botany, The University of Melbourne, Parkville, VIC 3010, Australia Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    X-ray scattering and microtomography (μCT) are useful techniques to reveal the structure of wood at the nano- and micrometer scales. The nanostructure of xylem in greenhouse-grown 2.5- to 3.5-month-old Populus tremula L. ×  tremuloides Michx. trees was characterized using wide-angle X-ray scattering (WAXS), and the cellular structure was investigated using μCT. For comparison, the nanostructure of wood in 2-year-old silver birch, Norway spruce and Scots pine saplings was determined. Based on the μCT results, the lengths of fiber lumina of the hybrid aspen saplings were shorter than any previous results on the lengths of wood fibers. The mean microfibril angles of the hybrid aspen saplings were significantly lower (8°–14°) than those of the birch, spruce and pine saplings (27°–35°) implicating that cellulose microfibrils were oriented nearly parallel to the cell axis in the young hybrid aspen saplings. Hybrid aspen saplings were found to contain tension wood based on the histochemical analysis and μCT images. However, typical tension wood properties, i.e. larger crystallite width and higher crystallinity than in normal wood, were detected only in a few hybrid aspen samples, while in most of the hybrid aspen saplings, the crystallite widths (3.0 ± 0.1 nm) and the crystallinities (30 ± 5 %) corresponded to those of normal wood. The deformations of cellulose crystallites were determined using WAXS in situ upon dehydration of the never-dried samples. In all the species studied, the cellulose unit cell dimension decreased and disorder of cellulose chains increased parallel to the chains upon drying. Also, the transverse disorder of chains increased in birch, spruce and pine, while no changes were detected in this direction in hybrid aspen. The crystallite widths and drying deformation results might indicate that the gelatinous layer has not fully developed in the young hybrid aspen saplings. Content Type Journal Article Category Original Paper Pages 1-12 DOI 10.1007/s00468-012-0748-x Authors Kirsi Svedström, Department of Physics, University of Helsinki, P.O.B. 64, 00014 University of Helsinki, Finland Jessica Lucenius, Department of Physics, University of Helsinki, P.O.B. 64, 00014 University of Helsinki, Finland Jan Van den Bulcke, UGCT-WOODLAB, Department of Forest and Water Management, Ghent University, Coupure Links 653, 9000 Ghent, Belgium Denis Van Loo, UGCT, Department of Physics and Astronomy, Ghent University, Proeftuinstraat 86, 9000 Ghent, Belgium Peter Immerzeel, Department of Forest Genetics and Plant Physiology, SLU, Umeå Plant Science Centre, 90183 Umeå, Sweden Jussi-Petteri Suuronen, Department of Physics, University of Helsinki, P.O.B. 64, 00014 University of Helsinki, Finland Loes Brabant, UGCT, Department of Physics and Astronomy, Ghent University, Proeftuinstraat 86, 9000 Ghent, Belgium Joris Van Acker, UGCT-WOODLAB, Department of Forest and Water Management, Ghent University, Coupure Links 653, 9000 Ghent, Belgium Pekka Saranpää, Finnish Forest Research Institute, P.O.B. 18, 01301 Vantaa, Finland Kurt Fagerstedt, Department of Biosciences, University of Helsinki, P.O.B. 65, 00014 University of Helsinki, Finland Ewa Mellerowicz, Department of Forest Genetics and Plant Physiology, SLU, Umeå Plant Science Centre, 90183 Umeå, Sweden Ritva Serimaa, Department of Physics, University of Helsinki, P.O.B. 64, 00014 University of Helsinki, Finland Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    Vertical leaf distribution and relative irradiance were ascertained for the dominant species Ulmus laevis Pall. at the level of the individual tree and at the level of the stand in a mixed broad-leaved forest in South Moravia, the Czech Republic. The study consisted of detailed, destructive measurement of five selected sample trees and the establishment of basic biometric parameters for the entire stand. Using allometric relationships, measurements from sample trees were generalized to diameter at breast height (DBH) classes and were then scaled up to the level of the imaginary pure stand of elm; the selected independent variables were tree height and DBH. The vertical leaf distribution was unimodal in trees with smaller dimensions and bimodal in trees with larger dimensions. The leaf area index (LAI) of the stand was 4 (6.4 including the undergrowth), and the sunlit leaf area index (SLAI) was 1.7. Dominant trees had a higher proportion of sunlit leaf area than subdominant and suppressed trees. Determination of appropriate methods and intensity of thinning can lead to optimizing of irradiation control, vitality increase of the elm stands and subsequently to a higher resistance to Dutch elm disease vector and disease itself. Content Type Journal Article Category Original Paper Pages 1-12 DOI 10.1007/s00468-012-0747-y Authors Martin Šrámek, Institute of Forest Botany, Dendrology and Geobiocenology, Mendel University in Brno, Zemědělská 3, 61300 Brno, Czech Republic Jan Čermák, Institute of Forest Botany, Dendrology and Geobiocenology, Mendel University in Brno, Zemědělská 3, 61300 Brno, Czech Republic Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    Palaeoclimate proxies have demonstrated links between climate changes and volcanic activity. However, not much is known about the impact of volcanic eruptions on forest productivity. Here we used tree-ring width and annually resolved carbon and oxygen isotopic records from tree rings of Araucaria araucana (Molina) K. Koch, providing a centennial-scale reconstruction of tree ecophysiological processes in forest stands nearby the Lonquimay Volcano (Chile). We observed a mean decrease in tree-ring width following the major eruption of 1988 – 1990 (with aerosol emission), most probably caused by the modified ecological conditions due to acid rain and ash deposition, while a generally negative relationship between δ 13 C and δ 18 O would point to a decline in humidity and precipitation. More negative δ 13 C and lower δ 18 O values (positive correlation) following the major eruption of 1887–1890 (without aerosol emission) would suggest high stomatal conductance and moisture availability, though tree-ring width (and probably photosynthetic rate) was unaltered. At least for this sample of trees, in the case of eruption with large tephra emission, the beneficial effect of aerosol light scattering on tree productivity appears to be outweighed by the detrimental effect of eruption-induced toxic deposition. Signals of the two major eruptions of the past 200 years at Lonquimay were present in tree rings of nearby A. araucana . No unique response of tree functions to volcanic eruptions can be expected, but rather (1) the variable volcanic properties and (2) the complex interplay of diffuse light increase (aerosol scattering), air temperature decrease (cloud shading), and toxic deposition impact (volcanic ash), makes any prediction of tree growth and ecophysiological response very challenging. Content Type Journal Article Category Original Paper Pages 1-15 DOI 10.1007/s00468-012-0749-9 Authors Roberto Tognetti, Dipartimento di Bioscienze e Territorio, Università degli Studi del Molise, Contrada Fonte Lappone, 86090 Pesche, Italy Fabio Lombardi, Dipartimento di Bioscienze e Territorio, Università degli Studi del Molise, Contrada Fonte Lappone, 86090 Pesche, Italy Bruno Lasserre, Dipartimento di Bioscienze e Territorio, Università degli Studi del Molise, Contrada Fonte Lappone, 86090 Pesche, Italy Giovanna Battipaglia, Dipartimento di Scienze Ambientali, Seconda Università di Napoli, Via Vivaldi, 81100 Caserta, Italy Matthias Saurer, PSI, Paul Scherrer Institut, 5232 Villigen, Switzerland Paolo Cherubini, WSL, Swiss Federal Institute for Forest, Snow and Landscape Research, 8903 Birmensdorf, Switzerland Marco Marchetti, Dipartimento di Bioscienze e Territorio, Università degli Studi del Molise, Contrada Fonte Lappone, 86090 Pesche, Italy Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    Theories that incorporate the area-preserving rule of Leonardo da Vinci predict that the sum of the cross-sectional lumen area of xylem conduits (vessels or tracheids) is constant across different levels of branching. If true, this rule obtains the packing rule, according to which (1) vessel cross-sectional lumen area ( A ) will negatively and isometrically scale to vessel number per unit area ( N ) and (2) the distal to proximal vessel diameter ratio (DR =  D n +1 / D n ) should scale as the −1/2 power of the distal to proximal vessel number ratio (NR =  N n +1 / N n ), i.e., DR = NR −1/2 . Using data collected from the terminal twigs and the petioles of 60 temperate (27 evergreen and 33 deciduous) woody species from southwestern China, we determined the scaling relationships for A versus N and for DR versus NR. Analyses of the data revealed contrasting scaling exponents and normalization constants for A versus N and for DR versus NR and no consistent trend across the two species groupings or between the two organ types (as predicted by the area-preserving and packing rules). These results caution against applying these rules ubiquitously to all species or to different organ types (even on the same plant). Content Type Journal Article Category Original Paper Pages 1-9 DOI 10.1007/s00468-012-0742-3 Authors Hong Chen, Key Laboratory of Horticulture Science for Southern Mountainous Regions, Ministry of Education, Southwest University, Chongqing, 400715 China Karl J. Niklas, Department of Plant Biology, Cornell University, Ithaca, NY 14850, USA Shucun Sun, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041 China Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung: Context   This study investigates post-fire natural regeneration of Aleppo pine ( Pinus halepensis ) forests at Ilia region (Peloponnesus, Greece) following the catastrophic fire of 2007. Aims   The objective of this study is the prediction of P. halepensis post-fire regeneration at a regional scale through an integrated geographic information systems (GIS) model as a basis for post-fire management plans. Methods   The model was developed in three interconnected stages: (1) field data collection, (2) development of two prediction models (based on interpolation of field data and multi-criteria evaluation (MCE) that combined factors known to affect regeneration), and (3) combination of applied models using Bayesian statistics. Results   Post-fire pine regeneration presented high variation among the studied plots. Redundancy analysis revealed the positive effect of fallen branches and a negative correlation with altitude. Both modeling approaches (geostatistical and MCE) predicted the post-fire pine regeneration with high accuracy. A very significant correlation ( r  = 0.834, p  〈 0.01) was found between the combined final model and the actual number of counted seedlings, illustrating that less than 10 % of the studied area corresponds to sites of very low post-fire pine regeneration. Conclusions   The combination of GIS models increased the prediction success of different levels of pine regeneration. Low-altitude areas with low grass cover overlying tertiary deposits were proved the most suitable for pine regeneration, while stands developing on limestone proved least suitable. The proposed methodology provides management authorities with a sound tool to quickly assess Aleppo pine post-fire regeneration potential. Content Type Journal Article Category Original Paper Pages 1-11 DOI 10.1007/s13595-012-0222-3 Authors Kostas S. Poirazidis, WWF Greece, 21, Lembessi St., 11743 Athens, Greece Konstantina Zografou, WWF Greece, 21, Lembessi St., 11743 Athens, Greece Panagiotis Kordopatis, WWF Greece, 21, Lembessi St., 11743 Athens, Greece Dionissios P. Kalivas, Department of Natural Resources Management and Agricultural Engineering, Agricultural University of Athens, 75, Iera Odos, 118 55 Athens, Greece Margarita Arianoutsou, Department of Ecology and Systematics, National and Kapodistrian University of Athens, Panepistimiopolis, Ilisia, 15784 Athens, Greece Dimitrios Kazanis, Department of Ecology and Systematics, National and Kapodistrian University of Athens, Panepistimiopolis, Ilisia, 15784 Athens, Greece Evangelia Korakaki, WWF Greece, 21, Lembessi St., 11743 Athens, Greece Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560

Beschreibung: Conservation, ecology, restoration, and management of Mediterranean pines and their ecosystems: challenges under global change Content Type Journal Article Category Letter to the Editor Pages 1-3 DOI 10.1007/s13595-012-0221-4 Authors Eric Rigolot, INRA, UR629, Ecologie des Forêts Méditerranéennes (URFM), Site Agroparc, Domaine St Paul, 84914 Avignon cedex 9, France Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560

Beschreibung: Context   Since the 2003 drought and heat wave, there have been many reports of Douglas-fir decline and dieback in France. Given the climate change that is predicted, more frequent drought episodes could induce recurrent decline processes. The nature and background of this threat requires a careful assessment. Aims   The objectives of this study were: (1) to test the hypothesis that the major climate hazard that accounts for the decline in Douglas-fir growth is drought, and (2) to identify the main vulnerability factors involved. Methods   Decline and recovery of radial growth were quantified of Douglas-fir in two particularly affected regions with a dendroecological approach; 899 trees were sampled on 58 plots. Mean climate data, ecological and dendrometric stand characteristics were tested in order to identify potential vulnerability factors Results   A clear relationship was evidenced between growth and soil water deficit. A severe decline of radial growth was induced by the 2003 drought and was maintained during subsequent years due to recurrent drought episodes. Growth recovery at the stand level was enhanced by soil nutrient fertility. Conclusion   Radial growth of Douglas-fir is clearly driven by the intensity of drought. In a context of climate change, an adaptive silvicultural strategy is required in order to cope with more frequent drought events. To mitigate the frequency and the intensity of water shortage episodes, site selection must take into account not only local climate characteristic but also soil properties like maximum extractable water content. Soil nitrogen fertility was found to play a key role for an efficient recovery of radial growth after drought episodes and thus must be preserved. Content Type Journal Article Category Original Paper Pages 1-12 DOI 10.1007/s13595-012-0220-5 Authors Anne-Sophie Sergent, INRA, UR0588, Unit Genetic improvement and forest Physiology, F-45075 Orléans, France Philippe Rozenberg, INRA, UR0588, Unit Genetic improvement and forest Physiology, F-45075 Orléans, France Nathalie Bréda, INRA-UHP UMR 1137 Forest Ecology and Ecophysiology Unit, F-54280 Champenoux, France Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560

Beschreibung: Context   Clonal variation of flower production has been investigated thoroughly in coniferous tree species because of the importance of flowering in seed production from seed orchards. However, the inheritance of flower production by progeny test has not been previously studied well, so the heritability of male flower production of Cryptomeria japonica , the most important species for forestry and the main cause of pollinosis in Japan, was estimated to provide fundamental data for pollen control in seed orchards and plantation forests. Methods   Male flower production in C. japonica was investigated for three years using 20 full-sib families created by a diallel mating design with six parents using gibberellin treatment to promote flowering. Results   The narrow-sense individual tree heritability of male flower production in each year was estimated as ranging from 0.777 ± 0.339 to 1.050 ± 0.346 by sib analyses. The contribution of general combining ability to the total variance varied from 24.1 to 35.6 %. The highest contribution of specific combining ability was 1.42 %. By selecting the top 50 % of parental clones for reduced male flower production, the genetic gain in lowering male flower productivity was predicted as 46.1–53.0 %. Conclusion   Our results suggest that male flower production in C. japonica is under strong genetic control and that control of male flowering by breeding is possible with a well-designed program. Content Type Journal Article Category Original Paper Pages 1-9 DOI 10.1007/s13595-012-0223-2 Authors Miyoko Tsubomura, Forest Tree Breeding Center, Forestry and Forest Products Research Institute, 3809-1 Ishi, Juo, Hitachi, Ibaraki 319-1301, Japan Eitaro Fukatsu, Kyushu Regional Breeding Office, Forest Tree Breeding Center, Forestry and Forest Products Research Institute, 2320-5 Suya, Koshi, Kumamoto 861-1102, Japan Ryogo Nakada, Forest Tree Breeding Center, Forestry and Forest Products Research Institute, 3809-1 Ishi, Juo, Hitachi, Ibaraki 319-1301, Japan Yoko Fukuda, Hokkaido Regional Breeding Office, Forest Tree Breeding Center, Forestry and Forest Products Research Institute, 561-1 Bunkyodai, Midorimachi, Ebetsu, Hokkaido 069-0836, Japan Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560

Beschreibung:    Droughts are a cyclical disturbance in Mediterranean ecosystems and climate change models forecast an increase of their frequency and severity. Some experimental and observational studies have shown that co-occurring species may cope with drier conditions with different strategies and present different responses. Here, we investigate sap flow response to drought in order to explain the observed differential growth and mortality of Quercus ilex and Phillyrea latifolia at Prades Holm oak forest (NE Spain). We measured sap flow of these species and compared their diurnal, nocturnal and seasonal patterns and their relationship with environmental variables. Both species described qualitatively similar daily patterns, either during daylight or night. Sap flow rates were significantly higher in P. latifolia except in autumn and spring. P. latifolia was more sensitive to soil moisture. Nocturnal sap flow was detected in both species with no significant differences and hourly rates suffered a progressive increase from 3 a.m. to dawn in most sampled nights. Our results indicate a better adaptation of P. latifolia to this site as it can take better advantage of wet periods while maintaining higher sap flow rates during dry periods. Along with previous ecophysiological studies at the same location it may be inferred that at its drier distributional limit Q. ilex would be at disadvantage with respect to other species like P. latifolia , as the latter would cope better with increasing xeric conditions already occurring and further predicted for Mediterranean ecosystems. Our results also show nocturnal sap flow to be relevant in individual water losses in these two species as they can be up to 35–40 % of daily sap flow. Further research on the underlying mechanisms of this nocturnal sap flow is required since it may also enhance early morning CO 2 fixation or nutrient supply to leaves. Content Type Journal Article Category Original Paper Pages 1-9 DOI 10.1007/s00468-012-0741-4 Authors Adrià Barbeta, CREAF, Cerdanyola del vallès, 08193 Catalonia, Spain Romà Ogaya, CREAF, Cerdanyola del vallès, 08193 Catalonia, Spain Josep Peñuelas, CREAF, Cerdanyola del vallès, 08193 Catalonia, Spain Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    The aim of this study was to clarify the capability of Scots pine seeds ( Pinus sylvestris L.) of different origins to germinate and survive under waterlogging conditions. Seeds were used from one Spanish and three UK sources. All experiments were carried out in the glasshouse and under the optimum conditions for Scots pine seed to germinate and establish. A technique using inner and outer pots was used to produce four depths of waterlogging below the soil surface. Seed mass and viability were examined prior to use in the experiments. Waterlogging reduced germination, but an increase in time between sowing and waterlogging of up to 3 weeks and a watertable 〉4 cm below the surface greatly improved germination and seedling growth. Once established, seedling survival was remarkably tolerant of waterlogging, and seedlings survived 25 months even with the watertable at the soil surface. Seeds collected from trees on a floating bog in the English Midlands were least affected by waterlogging, but the variation among seed sources was small compared to the effects of the timing, depth and duration of waterlogging. Management implications are discussed. Content Type Journal Article Category Original Paper Pages 1-9 DOI 10.1007/s00468-012-0740-5 Authors Tarek A. Mukassabi, School of Life Sciences, Keele University, Huxley Building, Staffordshire, ST5 5BG UK Anthony Polwart, School of Life Sciences, Keele University, Huxley Building, Staffordshire, ST5 5BG UK Tim Coleshaw, Natural England, Attingham Park, Shrewsbury, UK Peter A. Thomas, School of Life Sciences, Keele University, Huxley Building, Staffordshire, ST5 5BG UK Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    There has been growing recent interest in the adaptations of tree species to seedling establishment in active northern temperate floodplains. In the case of Populus and Salix , most or all of the recent papers overlook a scattered, earlier literature showing that, in many Populus and Salix species, just after germination, the collet produces prominent hairs which, in young seedlings, may play an important role in anchorage and water absorption, the collet being the transition zone between the hypocotyl and the radicle. This earlier literature is briefly reviewed. The significance of collet hairs is then related to the very high seedling mortalities in riparian systems caused by high river flows (scour) or by drought stress arising from water level declines and coarse sediment textures. The need for work to establish just which species have collet hairs and to quantify the effect of collet hairs on anchorage and water absorption is emphasized. Content Type Journal Article Category Review Pages 1-5 DOI 10.1007/s00468-012-0738-z Authors R. F. Parsons, Department of Botany, La Trobe University, Bundoora, Victoria, 3086 Australia Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    The New York Pine Plains are a unique ecosystem with normal statured and a dwarfed variety of pitch pines ( Pinus rigida Mill.). Growing interspersed with the dwarf pines are trees of intermediate height and features. Several hypotheses have been put forward as to why some of the trees are dwarfed, but none have been substantiated. In this study, we tested whether dwarf or medium trees are hydraulically limited compared to normally growing trees. Granier style sap flux sensors were installed in three to six trees of each tree type and sap flux was measured in early August 2004. Sap flux measurements were scaled to crown stomatal conductance using leaf area to sapwood area ratios for each tree. Contrary to expectation, dwarf and medium stature trees had very low leaf area to sapwood area ratios, but high crown stomatal conductances compared to normal trees. Analyses of leaf area, ring widths, and crown stomatal conductance indicate that differences between normal, and dwarf and medium pines are not due to hydraulic limitation, but that stunted growth may be due to other causes. Content Type Journal Article Category Original Paper Pages 1-9 DOI 10.1007/s00468-012-0736-1 Authors D. W. Vanderklein, Department of Biology and Molecular Biology, Montclair State University, Science Hall 116, Montclair, NJ 07043, USA K. V. R. Schäfer, Department of Biological Sciences, Rutgers University, 195 University Ave., Newark, NJ 07102, USA J. Martinez-Vilalta, CREAF, 08193 Cerdanyola del Vallès, Spain Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    Wood density is an important plant trait that influences a range of ecological processes, including resistance to damage and growth rates. Wood density is highly dependent on anatomical characteristics associated with the conductive tissue of trees (xylem and phloem) and the fibre matrix in which they occur. Here, we investigated variation in the wood density of the widespread mangrove species Avicennia marina in the Exmouth Gulf in Western Australia and in the Firth of Thames in New Zealand. We assessed how variation in xylem vessel size, fibre wall thickness and proportion of phloem within the wood contributed to variation in wood density and how these characteristics were linked to growth rates. We found the wood density of A. marina to be higher in Western Australia than in New Zealand and to be higher in taller seaward fringing trees than in scrub trees growing high in the intertidal. At the cellular level, high wood density was associated with large xylem vessels and thick fibre walls. Additionally, wood density increased with decreasing proportions of phloem per growth layer of wood. Tree growth rates were positively correlated with xylem vessel size and wood density. We conclude that A. marina can have large xylem vessel sizes and high growth rates while still maintaining high wood density because of the abundance and thickness of fibres in which vessels are found. Content Type Journal Article Category Original Paper Pages 1-9 DOI 10.1007/s00468-012-0729-0 Authors Nadia S. Santini, The School of Biological Sciences, The University of Queensland, St Lucia, QLD 4072, Australia Nele Schmitz, General Botany and Nature Management, Vrije Universiteit Brussel, Brussels, Belgium Catherine E. Lovelock, The School of Biological Sciences, The University of Queensland, St Lucia, QLD 4072, Australia Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    Foliage dynamics of three functional tree types representing major components of the tropical montane evergreen forest in southern part of Central Ethiopia were compared. The species were Podocarpus falcatus (evergreen gymnosperm), Prunus africana (evergreen broadleaf), and Croton macrostachyus (facultative deciduous). The hypothesis examined is that in such tropical trees, endogenous control of foliage dynamics by the leaf life-spans (LLS) is largely dominant over external signals. Crown foliage turnover, leafiness of twigs, LLS, photosynthetic performance, respiration rate, specific leaf area, and relative growth rates of the stems were investigated. Foliage dynamics and leafiness of the twigs were monitored over 2 years while leaf traits were followed over 3 months. The degree of inter and intra-individual synchronization of foliage phenophases was examined to get an estimate of the contributions of endogenous and external signals to the dynamics of the foliages. Autoregression analysis indicated significant influence of the moisture regime on leaf sprouting of Croton and Podocarpus . During pronounced dry periods, new leaves were not developed. Analysis of phenological data using circular statistics revealed that in spite of strong inter-individual synchronization of leaf flush and fall ( Podocarpus and Croton ), the dynamics of individual parts of the crowns were less synchronized. LLS was independent of climate factors and it had substantial contribution to the control of foliage turnover. Moreover, examination of ecophysiological traits of developing leaves of the studied functional types showed differing patterns with LLS corroborating the ecophysiological characteristics. Although overlaid by fungal infestation, both the foliage and ecophysiological properties of Prunus resemble that of Podocarpus but the former exhibited a shorter LLS and slightly higher metabolic rates. Nevertheless, all species reacted positively to high moisture with respect to stem growth. In spite of largely differing weather conditions of the 2 years, direct competitive advantage of one of the species over the others could not be detected. Content Type Journal Article Category Original Paper Pages 1-18 DOI 10.1007/s00468-012-0723-6 Authors Yigremachew Seyoum, Department of Biology, Addis Ababa University, P.O. Box, 1176, Addis Ababa, Ethiopia Masresha Fetene, Department of Biology, Addis Ababa University, P.O. Box, 1176, Addis Ababa, Ethiopia Simone Strobl, Department of Plant Physiology and Bayreuth Centre for Ecology and Environmental Research (BAYCEER), University of Bayreuth, 95440 Bayreuth, Germany Erwin Beck, Department of Plant Physiology and Bayreuth Centre for Ecology and Environmental Research (BAYCEER), University of Bayreuth, 95440 Bayreuth, Germany Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    Metallothioneins are Cys-rich, low-molecular weight, metal-binding proteins. In this paper, we aimed to evaluate the roles of type 2 metallothionein in Kandelia candel ( KcMT2 ) by analyzing its mRNA expression in leaves in response to heavy metals, as well as the metal-binding properties of its protein. The transcriptional response of KcMT2 gene to different heavy metals (Zn, Cu, Pb and Cd) was measured using real-time quantitative PCR. The results showed that the gene was regulated by the four metals tested. Significant increase in the expression of KcMT2 mRNA was also found in response to Zn, Cu, Pb and Cd. To analyze further the possible roles of KcMT2 against heavy metals, it was expressed in Escherichia coli BL21 as a carboxy-terminal extension of glutathione- S -transferase (GST). The E. coli cells expressing GST-KcMT2 fusion protein showed higher growth compared to the control cells under Zn, Cu, Pb or Cd exposure, and the GST-KcMT2 fusion protein had a stronger binding affinity for Zn, Cu, Pb and Cd than GST alone. Results presented here reveal that KcMT2 may play important roles in the heavy metal homeostasis or detoxification. Content Type Journal Article Category Original Paper Pages 1-8 DOI 10.1007/s00468-012-0727-2 Authors Guo-Yong Huang, Key Laboratory of Tropical Marine Environmental Dynamics, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301 China You-Shao Wang, Key Laboratory of Tropical Marine Environmental Dynamics, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301 China Guang-Guo Ying, State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640 China Ai-Cui Dang, Key Laboratory of Tropical Marine Environmental Dynamics, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301 China Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    Riparian ecotones in the fynbos biome of South Africa are heavily invaded by woody invasive alien species, which are known to reduce water supply to downstream environments. To explore whether variation in species-specific functional traits pertaining to drought-tolerance exist, we investigated wood anatomical traits of key native riparian species and the invasive Acacia mearnsii across different water availability proxies. Wood density, vessel resistance against implosion, vessel lumen diameter and vessel wall thickness were measured. Wood density varied significantly between species, with A. mearnsii having denser wood at sites in rivers with high discharge. As higher wood density is indicative of increased drought tolerance and typical of drier sites, this counter-intuitive finding suggests that increased wood density was more closely related to midday water stress, than streamflow quantity per se. Wood density was positively correlated with vessel resistance against implosion. Higher wood density may also be evidence that A. mearnsii is more resistant against drought-induced cavitation than the studied native species. The observed plastic response of A. mearnsii anatomical traits to variable water availability indicates the ability of this species to persist under various environmental conditions. A possible non-causal relationship between wood anatomy and drought tolerance in these riparian systems is discussed. Content Type Journal Article Category Original Paper Pages 1-10 DOI 10.1007/s00468-012-0726-3 Authors Casparus J. Crous, Department of Conservation Ecology and Entomology, Stellenbosch University, Private Bag X1, Matieland, 7602 South Africa Shayne M. Jacobs, Department of Conservation Ecology and Entomology, Stellenbosch University, Private Bag X1, Matieland, 7602 South Africa Karen J. Esler, Department of Conservation Ecology and Entomology, Stellenbosch University, Private Bag X1, Matieland, 7602 South Africa Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    To fulfill the US Thanksgiving and Christmas tree markets, balsam fir ( Abies balsamea (L.) Mill.) is generally harvested before the cold season, anecdotally leading to premature needle senescence. Accordingly, we tested the hypothesis that LT exposure before harvest induces specific hormonal changes and delays postharvest senescence and/or abscission in balsam fir. Two hundred and six seedlings exposed to two temperature treatments for 48 h, LT at 5 °C and controls at 22 °C were severed off roots and monitored for their postharvest needle senescence. Root and shoot (needles and buds) tissues were examined for major endogenous hormone metabolites. LT increased shoot ABA (2,007 ng g −1 DW) by 2.5× and decreased GA 44 (9.84 ng g −1 DW) by 3.5× over those in roots. LT did not alter cytokinins, auxins or any root hormonal concentration. With auxins, only IAA, IAA-Asp, IAA-Leu and IAA-Glu were detected and the concentrations of IAA and IAA-Asp in shoots were lower than those found in roots. Among cytokinins, shoot c-ZR (58.95 ng g −1 DW) and t-ZR (4.17 ng g −1 DW) were 3× higher than those in roots. Apart from GA 44 , GA 9 (136.76 ng g −1 DW) was abundant in shoots. The PBL and PNL were 46 and 1.2 %, irrespective of treatments. LT seedlings held needles 11 days longer than the controls (122 days). In balsam fir, short-term LT exposure augmented ABA and decreased GA 44 levels in shoots and delayed postharvest needle senescence. Content Type Journal Article Category Original Paper Pages 1-9 DOI 10.1007/s00468-012-0728-1 Authors Arumugam Thiagarajan, Department of Environmental Sciences, Christmas Tree Research Center, Nova Scotia Agricultural College, Truro, NS B2N 5E3, Canada Rajasekaran Lada, Department of Environmental Sciences, Christmas Tree Research Center, Nova Scotia Agricultural College, Truro, NS B2N 5E3, Canada Steeve Pepin, Centre de recherche en horticulture, Université Laval, Quebec, QC G1V 0A6, Canada Charles Forney, Atlantic Food and Horticulture Research Centre, Agriculture and AgriFood Canada, Kentville, NS B4N 1J5, Canada Yves Desjardins, Centre de recherche en horticulture, Université Laval, Quebec, QC G1V 0A6, Canada Martine Dorais, Centre de recherche en horticulture, Université Laval, Quebec, QC G1V 0A6, Canada Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    During the last few years, considerable effort has been directed toward understanding how Eucalyptus globulus responds and adapts to low temperature due to its low freezing resistance, especially through gene expression analysis. A recent study has confirmed that freezing stress induces the expression of three dehydrin (DHN) genes in E. globulus . This work reports the identification of a new YSK-type DHN gene in E. globulus ( EuglDHN3 ) and examines the responses of this gene and the three previously reported ( EuglDHN1 , EuglDHN2 and EuglDHN10 ) under low temperature (LT), short photoperiod and water deficit (WD) in one sensitive and one freezing-resistant genotype of E. globulus , to assign them to a class: low temperature responsive, photoperiod responsive or water deficit responsive. Results indicated that two SK n -type DHNs ( EuglDHN1 and EuglDHN2 ) were strongly induced by LT and WD, the KS-type DHN ( EuglDHN10 ) was strongly induced by LT and the Y n SK n -type by WD. The expression patterns under LT and WD were consistent with the regulatory elements identified in the promoter regions of the four DHN genes. The differential accumulation of EuglDHN1 , EuglDHN2 and EuglDHN3 transcripts suggests a differential regulation in specific tissues under WD, and EuglDHN1 and EuglDHN10 under LT. Content Type Journal Article Category Original Paper Pages 1-11 DOI 10.1007/s00468-012-0722-7 Authors Marta Fernández, Faculty of Forest Sciences, University of Concepción, Concepcion, Chile Sofia Valenzuela, Faculty of Forest Sciences, University of Concepción, Concepcion, Chile Hita Barraza, Faculty of Forest Sciences, University of Concepción, Concepcion, Chile Javier Latorre, Faculty of Forest Sciences, University of Concepción, Concepcion, Chile Valeria Neira, Genomica Forestal S.A, Concepcion, Chile Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    The phenology of tree species in environments that are subject to strong climatic seasonality is mainly determined by water availability, which may vary as a function of wood density. The relationship among phenology, water potential, wood density and the capacity of water storage in the stem were determined for woody species of caatinga vegetation (dry forest) in the semiarid region of NE Brazil. Leaf flush and fall, flowering and fruiting events were recorded over a 31-month period, and the water potential was measured over a two-year period. These data were related to precipitation, water availability in the soil and photoperiod. Seven deciduous species exhibited low wood density (DLWD, 〈0.5 g cm −3 ), high capacity of water storage in the stem (until 250 % of the dry weight) and high water potential during the year, as opposed to 15 deciduous species that showed high wood density (DHWD, ≥0.5 g cm −3 ). Leaf flush, flowering and the fruiting of DHWD species were related to precipitation, whereas these phenological events occurred at the end of the dry season and/or the beginning of the rainy season for DLWD species and were related to the photoperiod. The two evergreen species showed variations of water potential that were intermediate between those of DHWD and DLWD deciduous species, leaf flush during the dry season and flowering at the end of dry season. These results suggest the existence of three functional groups: evergreen species, DHWD deciduous species and DLWD deciduous species. Content Type Journal Article Category Original Paper Pages 1-12 DOI 10.1007/s00468-012-0735-2 Authors André Luiz Alves de Lima, Universidade Federal Rural de Pernambuco (UFRPE), Unidade Acadêmica de Serra Talhada (UAST), Fazenda Saco s/n, Caixa Postal 063, 56900-000 Serra Talhada, Pernambuco, Brazil Everardo Valadares de Sá Barretto Sampaio, Centro de Tecnologia, Departamento de Energia Nuclear, Universidade Federal de Pernambuco (UFPE), Av. Prof. Luís Freire 1000, Cidade Universitária, 50740-540 Recife, Pernambuco, Brazil Cibele Cardoso de Castro, Universidade Federal Rural de Pernambuco, Unidade Acadêmica de Garanhuns, Avenida Bom Pastor, s/n-Boa Vista, 55296-901 Garanhuns, Pernambuco, Brazil Maria Jesus Nogueira Rodal, Departamento de Biologia/Área de Botânica, Universidade Federal Rural de Pernambuco (UFRPE), Rua Dom Manoel de Medeiros s/n, Dois Irmãos, 52171-900 Recife, Pernambuco, Brazil Antônio Celso Dantas Antonino, Centro de Tecnologia, Departamento de Energia Nuclear, Universidade Federal de Pernambuco (UFPE), Av. Prof. Luís Freire 1000, Cidade Universitária, 50740-540 Recife, Pernambuco, Brazil André Laurênio de Melo, Universidade Federal Rural de Pernambuco (UFRPE), Unidade Acadêmica de Serra Talhada (UAST), Fazenda Saco s/n, Caixa Postal 063, 56900-000 Serra Talhada, Pernambuco, Brazil Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    Despite numerous studies on nitrogen (N) cycling in forest ecosystems, many uncertainties remain, particularly regarding long-term N accumulation in the soil. Models validated against tracer isotopic data from field labeling experiments provide a potential tool to better understand and simulate C and N interactions over multiple decades. In this study, we describe the adaptation of the dynamic process-based model TRACE to a new site, Alptal, where long-term N-addition and 15 N-tracer experiments provide unique datasets for testing the model. We describe model parameterization for this spruce forest, and then test the model with 9- and 14-year time series of 15 N-tracer recovery from control and N-amended catchments, respectively. Finally, we use the model to project the fate of ecosystem N accumulation over the next 70 years. Field 15 N recovery data show that the major sink for N deposition is the soil. On the control plot, tracer recovery in the soil increased from 32 % in the second year to 60 % in the ninth year following tracer addition, whereas on the N-saturated plot, soil recovery stayed almost constant from 63 % in the third year to 61 % in the twelfth year. Recovery in tree biomass increased over the decadal time scale in both treatments, to ca. 10 % over 9 years on the control plot and ca. 13 % over 14 years on the N-amended plot. We then used these time series to validate TRACE, showing that the adaptation and calibration procedure for the Alptal site was successful. Model-data comparison identified that the spreading method of 15 N tracers needs to be considered when interpreting recovery results from labeling studies. Furthermore, the ground vegetation layer was recognized to play an important role in controlling the rate at which deposited N enters soil pools. Our 70-year model simulation into the future underpinned by a Monte-Carlo sensitivity analysis, suggests that the soil is able to immobilize a constant fraction of 70 and 77 % of deposited N for the treated and the control plot, respectively. Further, the model showed that the simulated increased N deposition resulted in a relatively small elevated C sequestration in aggrading wood with an N use efficiency of approximately 7 kg C per kg N added. Content Type Journal Article Category Original Paper Pages 1-20 DOI 10.1007/s00468-012-0737-0 Authors Kim Krause, Swiss Fed. Inst. for Forest Snow and Landscape Research (WSL), 8903 Birmensdorf, Switzerland Isabelle Providoli, Centre for Development and Environment, University of Bern, 3012 Bern, Switzerland William S. Currie, School of Natural Resources and Environment, University of Michigan, Ann Arbor, USA Harald Bugmann, Forest Ecology, Swiss Fed. Inst. of Technology (ETH), 8092 Zurich, Switzerland Patrick Schleppi, Swiss Fed. Inst. for Forest Snow and Landscape Research (WSL), 8903 Birmensdorf, Switzerland Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    Defoliation by herbivores may alter the source:sink balance of trees leading to transient decreases in carbon (C) stores. When C stores are replenished concurrently with re-growth both processes may compete, store formation proceeding at the expenses of growth. However, the interactions between both processes are not fully understood. We investigated the effects of defoliation by the pine processionary moth (PPM, Thaumetopoea pityocampa Dennis and Schiff.) on the non-structural carbohydrate (NSC) and nitrogen (N) stores and the growth of Pinus nigra Arnold trees. Short-term effects were evaluated immediately after a PPM outbreak and at the end of the first growing season in trees suffering a range of defoliation damage. Long-term effects were explored by a 17-year-long PPM defoliation experiment, with 11 years of repeated defoliation treatments followed by 6 years of recovery. Defoliation by PPM was followed by transient NSC decreases, but trees were able to exceed initial NSC pools and compensate growth in just one growing season. Such recovery was linked to increased foliage N. Repeated severe defoliations decreased growth and survival of trees in the long-term, but trees increased starch allocation to stems. Defoliation led to an accumulation of C storage compounds in P. nigra trees irrespective of their ability to re-grow. In trees included in the short-term experiment, the accumulation of stores proceeded concurrently with re-growth. However, the repeated severe defoliations included in our long-term experiment impaired the growth of trees, surplus C being accumulated as stores. These results indicate that, growth declines in pines defoliated by PPM are not due to C (source) limitation but may respond to the reduced sink strength of growing meristems due to defoliation, and thus, a decrease in C allocation to growth. Content Type Journal Article Category Original Paper Pages 1-14 DOI 10.1007/s00468-012-0739-y Authors Sara Palacio, Pyrenean Institute of Ecology (IPE-CSIC), Avda. Nuestra Sra. de la Victoria s/n Apdo. 64, 22700 Jaca, Huesca, Spain Rodolfo Hernández, Laboratorio de Sanidad Forestal, Servicio Provincial de Medio Ambiente de Teruel, Depto. Medio Ambiente, Gob. Aragón, C/Agustín Planas Sancho 10, 44400 Mora de Rubielos, Teruel, Spain Melchor Maestro-Martínez, Pyrenean Institute of Ecology (IPE-CSIC), Av. Montañana, 1005 Apdo. 13034, 50080 Zaragoza, Spain J. Julio Camarero, ARAID, Pyrenean Institute of Ecology (IPE-CSIC), Av. Montañana, 1005 Apdo. 13034, 50080 Zaragoza, Spain Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung: • Introduction, Material and Methods   The genetic structure and diversity of ten natural populations of Juniperus phoenicea L. from the western part of the species range have been studied using random amplified polymorphic DNA (RAPD) markers. • Results and discussion   Among 10 analyzed primers only 3 reproduced consistently across successful PCR reactions and gave 45 loci. The percentage of polymorphic loci ( P ) and Nei’s heterozygosity ( H e ) have average values of 64.9% and 0.177. The average expected heterozygosity of particular populations positively correlate with latitude and negatively with altitude ( τ  = 0.556, P  = 0.025; τ  = −0.494, P  = 0.047, respectively). The proportion of genetic variation contributed by the differences between populations was low ( G ST   =  0.056). The gene flow ( N m ) has an average value of 4.2, and was higher in subsp. turbinata (7.3) than in subsp. phoenicea (4.1). Significant proportion of the variation (Φ ST  = 0.106) was attributable to differences among populations, as revealed in analysis of molecular variance analysis of pair-wise RAPD distances. No evidence for isolation by distance was detected in Mantel test on genetic (Φ ST ) and geographic distances. European populations differed at a higher level from the African, subsp. phoenicea from turbinata (3.97% and 3.14% of total variance, respectively). The significant level of differences between European and African populations can result from (1) the earlier divergence and considerably low level of gene flow between them, or (2) a different mutation rate within population of different continent. • Conclusion   The results suggest rather local forest economy with J. phoenicea , without seed exchange on large distance. Content Type Journal Article Category Original Paper Pages 1341-1350 DOI 10.1007/s13595-011-0150-7 Authors Artur Dzialuk, Department of Genetics, Kazimierz Wielki University, Chodkiewicza 30, 85-064 Bydgoszcz, Poland Małgorzata Mazur, Department of Botany, Kazimierz Wielki University, Al. Ossolińskich 12, 85-093 Bydgoszcz, Poland Krystyna Boratyńska, Polish Academy of Sciences, Institute of Dendrology, Parkowa 5, 63-036 Kórnik, Poland Jose M. Montserrat, Institut de Cultura de Barcelona, Jardí Botànic de Barcelona, C/ Font i Quer 2, 08038 Barcelona, Spain Angel Romo, Botanical Institute of Barcelona (CSIC-ICUB), Passeig del Migdia s/n. Parc de Montjuïc, 08038 Barcelona, Spain Adam Boratyński, Polish Academy of Sciences, Institute of Dendrology, Parkowa 5, 63-036 Kórnik, Poland Journal Annals of Forest Science Online ISSN 1297-966X Print ISSN 1286-4560 Journal Volume Volume 68 Journal Issue Volume 68, Number 8

Beschreibung:    Belowground tree growth attributes determine whether associations will be complementary or competitive in an agroforestry context. A study on fine root ( d  ≤ 2 mm) distribution patterns of Dacryodes edulis based on root density (RD), root length density (RLD) and root weight density (RWD) was conducted to evaluate the effect of propagation methods on rooting distribution. Results showed that D. edulis trees of seed origin had greater RD ( P  ≤ 0.001) than trees of vegetative origin (cuttings and marcots) in the upper soil stratum (0–30 cm). Similarly, in the uppermost soil stratum (0–10 cm), RLD and RWDs varied significantly ( P  〈 0.01). Trees of seed origin had an exponential distribution pattern for fine RD, RLD and RWD with depth to 80 cm. In contrast, the distribution pattern of fine roots of trees of vegetative origin (cuttings and marcots) were quadratic for the same variables which increased in the 20–30 cm soil depth stratum before declining steadily to a depth of 80 cm. The findings of this study suggest that D. edulis trees of vegetative origin (cuttings and marots) are likely to be less competitive than trees of seed origin when intercropped with shallow-rooted annual plants in an agroforestry system for belowground resources. Content Type Journal Article Category Original Paper Pages 1-9 DOI 10.1007/s00468-012-0720-9 Authors E. K. Asaah, World Agroforestry Centre (ICRAF), West and Central Africa Regional Program, BP 16317, Yaounde, Cameroon T. N. Wanduku, The World Vegetable Center (AVRDC), Liaison Office Cameroon, Yaounde, Cameroon Z. Tchoundjeu, World Agroforestry Centre (ICRAF), West and Central Africa Regional Program, BP 16317, Yaounde, Cameroon L. Kouodiekong, World Agroforestry Centre (ICRAF), West and Central Africa Regional Program, BP 16317, Yaounde, Cameroon P. Van Damme, Faculty of Bioscience Engineering, University of Ghent, Ghent, Belgium Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    This review presents a new conceptual model for the involvement of low molecular flavanols in chromatin remodelling and genome organization. The experiments are based on the property of flavanols to associate with nuclei as revealed by blue staining after treatment with the p -dimethylaminocinnamaldehyde reagent. From a critical standpoint, this puzzling finding is nearly incompatible with current views about nuclear organization. Therefore, it was necessary to collect a whole host of data to confirm this new aspect and to gain some insight into possible regulatory roles of histone–flavanol assemblies. A lot of research has been devoted to this topic over the last 13 years. In particular, conifer nuclei were found to contain flavanols, whereas the nuclei of most angiospermous tree species investigated until now reacted negatively. Camellia sinensis (tea bush), being a broad-leaved dicotyledonous species indeed has nuclei with prominent flavanol staining. A subnuclear patterning of flavanols can be observed which is regulated by genetic and epigenetic mechanisms. Broadly speaking, flavanols of nuclei range from evenly diffuse to mosaic-like mottling and from pale to dark blue. The diffuse type is apparently characteristic of a more silenced nuclear state, whilst mild to prominent mottling implicates a transcriptionally more activated state. Dark blue flavanol blobs within the mottled mosaic state indicate a heterochromatin pattern whilst pale blue stippling tends to euchromatin. Environmental stress conditions such as drought combined with heat induce key signals for down-regulation of nuclear flavanols. In this article, various aspects of nuclear flavanol localization are summarized and discussed. Content Type Journal Article Category Review Pages 1-13 DOI 10.1007/s00468-012-0725-4 Authors Walter Feucht, Unit Fruit Science, Center of Life Sciences Weihenstephan, Technische Universität München, Dürnast 2, 85354 Freising, Germany Dieter Treutter, Unit Fruit Science, Center of Life Sciences Weihenstephan, Technische Universität München, Dürnast 2, 85354 Freising, Germany Jürgen Polster, Unit Physical Biochemistry, Centre of Life Sciences Weihenstephan, Technische Universität München, 85354 Freising, Germany Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    Citrus species are sensitive to an excess of boron (B). Currently, this toxicity is becoming a serious problem in the soils of arid and semi-arid environments throughout the world, where high concentrations of B may occur due to the agricultural use of wastewater. Citrus rootstocks can greatly influence the tolerance of citrus trees to different abiotic stresses. However, little is known about how the rootstock influences the tolerance of these trees to an excess of B. In this study, the effects of the nutrient solution’s B concentration (0.25, 2, 4.5 or 7 mg l −1 ) on the growth and other physiological, nutritional and biochemical parameters of Verna lemon trees that were grafted on four contrasting rootstocks [Carrizo citrange (CC), Cleopatra mandarin (CL), Citrus macrophylla (CM) and sour orange (SO)] were investigated. The plants were grown in a greenhouse in pots containing a universal substrate media and were watered daily with a Hoagland nutrient solution containing different concentrations of B. The results showed that the plant growth was progressively inhibited with an increasing concentration of B in the nutrient solution. However, the shoot was more sensitive to the B toxicity than were the roots. In addition, the growth inhibition was reduced in trees that were grafted on CL and CM when compared with those that were grafted on CC and SO. The concentration of B in the leaves, stems and roots also increased with an increase in the concentration of external B in the following order: leaves 〉 roots 〉 stem. The rootstock also had an influence on the B concentration in the different plant tissues. In the leaves, the B concentration was lowest in the plants that were grafted on the SO rootstock followed by the plants that were grafted on either the CM or CL rootstock and highest in the plants that were grafted on the CC rootstock. The net assimilation of CO 2 ( A \text CO 2 ) and the stomatal conductance ( g s ) leaf gas exchange parameters were reduced with an excess of B in the leaves, and this reduction was less pronounced for trees on CM and CL. The intercellular CO 2 concentration ( C i ) and the chlorophyll fluorescence indicated that the reduction of A \text CO 2 that was found with an excess of B was mainly due to non-stomatal factors. The mineral nutrition and organic solute data are also shown in this study. All of the data indicate that the tolerance to an excess of B is not related to the concentration of B that has accumulated in the leaves, which indicates that a combination of rootstock-dependent physiological, biochemical and anatomical responses determine the tolerance to an excess of B in citrus plants. Content Type Journal Article Category Original Paper Pages 1-14 DOI 10.1007/s00468-012-0724-5 Authors Vicente Gimeno, Centro de Edafología y Biología Aplicada del Segura, CSIC, Campus Universitario de Espinardo, 30100 Espinardo, (Murcia), Spain Inma Simón, EPSO (Univ. Miguel Hernández), Ctra. Beniel km 3,2, 03312 Orihuela, (Alicante), Spain Manuel Nieves, EPSO (Univ. Miguel Hernández), Ctra. Beniel km 3,2, 03312 Orihuela, (Alicante), Spain Vicente Martínez, Centro de Edafología y Biología Aplicada del Segura, CSIC, Campus Universitario de Espinardo, 30100 Espinardo, (Murcia), Spain José M. Cámara-Zapata, EPSO (Univ. Miguel Hernández), Ctra. Beniel km 3,2, 03312 Orihuela, (Alicante), Spain Antonio L. García, Facultad de Química, Universidad de Murcia.Campus Universitario de Espinardo, 30071 Espinardo, (Murcia), Spain Francisco García-Sánchez, Centro de Edafología y Biología Aplicada del Segura, CSIC, Campus Universitario de Espinardo, 30100 Espinardo, (Murcia), Spain Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    Tropospheric ozone (O 3 ) is a critical threat to forest ecosystems. A stomatal flux-based risk evaluation methodology at the leaf level was established recently in the context of the Convention on Long-Range Transboundary Air Pollution (LRTAP). This study demonstrates improvement and validation of the stomatal flux-effect approach for adult beech with results from the 8-year free-air O 3 enrichment experiment at “Kranzberger Forst” (Germany). The risk assessment module of the SVAT model FO 3 REST, being under development for local scale O 3 -risk assessment of adult beech stands, was parameterized according to the LRTAP Convention’s Mapping Manual. Mean maximum stomatal conductance for water vapour of 245 mmol H 2 O m −2 PLA s −1 , as suggested in the LRTAP Convention’s Mapping Manual for beech, was affirmed by assessment at “Kranzberger Forst”, resulting in 162 mmol O 3 m −2 PLA s −1 upon recommended adjustment of the O 3 /water vapour diffusivity ratio to 0.663. Based on this ratio, a provisional corrected flux-effect function was deduced. Modelled Phytotoxic O 3 Doses ( POD 1 ) and potential O 3 -caused losses in biomass formation estimated with a site-specific stomatal conductance algorithm differed slightly only from estimates by the original LRTAP parameterisation. Analysis-derived POD 1 target value within the meaning of Article 2 of the European Council Directive 2008/50/EC of 10 mmol O 3 m −2 corresponded to potential loss in biomass formation of about 10 % in ambient air relative to “pre-industrial” conditions. However, exceedance occurred by about a factor of two during the study period, indicating high risk at “Kranzberger Forst” under ambient air. Assessment for doubled O 3 exposure indicated potential underestimation even of the O 3 risk because modelled losses in biomass formation are in the lower range of the standard deviation of the observed ones. Content Type Journal Article Category Original Paper Pages 1-9 DOI 10.1007/s00468-012-0716-5 Authors Ludger Grünhage, Department of Plant Ecology, Justus-Liebig University, Heinrich-Buff-Ring 26, 35392 Giessen, Germany Rainer Matyssek, Ecophysiology of Plants, Technische Universität München, Wissenschaftszentrum Weihenstephan, Hans-Carl-von-Carlowitz-Platz 2, 85354 Freising, Germany Karl-Heinz Häberle, Ecophysiology of Plants, Technische Universität München, Wissenschaftszentrum Weihenstephan, Hans-Carl-von-Carlowitz-Platz 2, 85354 Freising, Germany Gerhard Wieser, Division of Alpine Timberline Ecophysiology, Federal Research and Training Centre for Forests, Natural Hazards and Landscape, Rennweg 1, 6020 Innsbruck, Austria Ursula Metzger, Ecophysiology of Plants, Technische Universität München, Wissenschaftszentrum Weihenstephan, Hans-Carl-von-Carlowitz-Platz 2, 85354 Freising, Germany Michael Leuchner, Ecoclimatology, Technische Universität München, Wissenschaftszentrum Weihenstephan, Hans-Carl-von-Carlowitz-Platz 2, 85354 Freising, Germany Annette Menzel, Ecoclimatology, Technische Universität München, Wissenschaftszentrum Weihenstephan, Hans-Carl-von-Carlowitz-Platz 2, 85354 Freising, Germany Jochen Dieler, Forest Growth and Yield Science, Technische Universität München, Wissenschaftszentrum Weihenstephan, Hans-Carl-von-Carlowitz-Platz 2, 85354 Freising, Germany Hans Pretzsch, Forest Growth and Yield Science, Technische Universität München, Wissenschaftszentrum Weihenstephan, Hans-Carl-von-Carlowitz-Platz 2, 85354 Freising, Germany Winfried Grimmeisen, Bayerische Landesanstalt für Wald und Forstwirtschaft, Hans-Carl-von-Carlowitz-Platz 1, 85354 Freising, Germany Lothar Zimmermann, Bayerische Landesanstalt für Wald und Forstwirtschaft, Hans-Carl-von-Carlowitz-Platz 1, 85354 Freising, Germany Stephan Raspe, Bayerische Landesanstalt für Wald und Forstwirtschaft, Hans-Carl-von-Carlowitz-Platz 1, 85354 Freising, Germany Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890

Beschreibung:    Plasticity of biomass allocation is a key to growth and survival of trees exposed to variable levels of stress in their lifetime. Most of our understanding of dynamic biomass allocation comes from seedling studies, but plasticity may be different in mature trees. We used stem analysis to reconstruct whole-tree growth and biomass allocation patterns in Quercus pubescens trees harvested from a dry woodland in Valais, Switzerland. We identified three distinct growth phases. In phase I, a primary root developed but the aboveground structure did not persist. In phase II, height growth occurred and secondary roots developed. In phase III, height growth ceased and stems and roots only grew radially. Reference trees harvested from a less dry site nearby only showed phase II-type growth. In line with our hypothesis, drought-stressed trees maintained more biomass in roots and less in aboveground woody parts than reference trees. Contrary to our expectation, stressed trees allocated proportionally more resources to leaves and less to roots in the growing season before harvest than reference trees. It appears that sub-seasonal wood anatomical adjustments to water availability minimize hydraulic failure, thus enabling these dry woodland trees to invest preferentially in leaves. Wet years did not see preferential investment in aboveground tissues, suggesting more restricted plasticity in biomass allocation in these mature trees than in seedlings. It is concluded that trees beyond seedling stage show different responses to variation in drought than the better-studied seedlings. Content Type Journal Article Category Short Communication Pages 1-8 DOI 10.1007/s00468-012-0717-4 Authors Martijn Slot, Swiss Federal Research Institute WSL, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland Stijntje H. Janse-ten Klooster, Swiss Federal Research Institute WSL, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland Frank J. Sterck, Forest Ecology and Forest Management Group, Wageningen University, P.O. Box 47, 6700 AA Wageningen, The Netherlands Ute Sass-Klaassen, Forest Ecology and Forest Management Group, Wageningen University, P.O. Box 47, 6700 AA Wageningen, The Netherlands Roman Zweifel, Swiss Federal Research Institute WSL, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland Journal Trees - Structure and Function Online ISSN 1432-2285 Print ISSN 0931-1890