ALBERT

Description:    There is a lack of knowledge to identify and classify forest structures according to the risk of crown fires, especially in Mediterranean regions. In this study, for the first time, we use real information, obtained after a wildfire that burnt under extreme meteorological conditions, to classify forest structures of Pinus halepensis into fuel types as a function of crown fire potential. We identified fourteen forest structures which characterize many forest types in Western Mediterranean areas depending on canopy closure, number of tree layers, percent of each tree layer and overall tree density. By using the pattern of fire types that burnt the most numerous forest structures, we have identified four fire hazard groups of forest structures which are considered different fuel types. The first two had the lowest risk of active crown fires and they differed in the proportion of surface fires and passive crown fires. The third fuel type was the threshold between structures with low and high extreme fire behavior; while the fourth had a high risk of active crown fires. Firefighters and forest managers who are demanding this kind of schema, will test and upgrade this classification of fuel types in function of crown fire potential during future wildfires. Content Type Journal Article Pages 1-12 DOI 10.1007/s10342-011-0520-6 Authors Albert Alvarez, CREAF (Centre for Ecological Research and Forestry Applications) and Unit of Ecology, Campus Autonomous University of Barcelona, 08193 Bellaterra, Barcelona, Spain Marc Gracia, CREAF (Centre for Ecological Research and Forestry Applications) and Unit of Ecology, Campus Autonomous University of Barcelona, 08193 Bellaterra, Barcelona, Spain Javier Retana, CREAF (Centre for Ecological Research and Forestry Applications) and Unit of Ecology, Campus Autonomous University of Barcelona, 08193 Bellaterra, Barcelona, Spain Journal European Journal of Forest Research Online ISSN 1612-4677 Print ISSN 1612-4669

Description:    This study aims at the explanation of internal stem morphology of vital (co)dominant Pedunculate oak ( Quercus robur L.) trees in homogeneous even-aged high-forests by the factors tree age, forest structure and site quality, using boosted regression trees as a powerful modelling technique. The study area covers the region of Flanders (Northern Belgium), which is characterised by the absence of strong topographic and climatic gradients. For 76 adult sample trees covering the entire productivity range of Pedunculate oak, morphological characteristics were derived from measurements of ring width or heartwood area on wood cores. Forest structure, soil physicochemical properties, humus quality, vegetation indices and litter nutrient contents were quantified at each sample location. Model predictive performance and generality are good. Tree age effects correspond to expected trends in age-related radial growth and heartwood portion. Even if management of oak trees in even-aged high-forests is rather similar over Flanders, forest structure is the most important factor determining ring width, followed by soil fertility. Heartwood portion is determined by soil fertility and crown structure. Effects of topsoil and humus physicochemical characteristics, litter nutrient contents and water supply mainly confirm autecological knowledge on oak. However, variables related to soil water availability are only occasionally relevant, and always of lower importance than soil fertility. The low importance of water availability in the models contradicts results from other studies, and the potential effect of confounding is discussed. The observed growth reduction at low litter N/P ratios might be indirectly linked to early litterfall. Content Type Journal Article Pages 1-14 DOI 10.1007/s10342-011-0535-z Authors Vincent Kint, Division Forest, Nature and Landscape, Department of Earth and Environmental Sciences, K.U.Leuven, Celestijnenlaan 200E, Box 2411, 3001 Leuven, Belgium Dries Vansteenkiste, Laboratory of Wood Technology, Department of Forest and Water Management, Ghent University, Coupure Links 653, 9000 Ghent, Belgium Wim Aertsen, Division Forest, Nature and Landscape, Department of Earth and Environmental Sciences, K.U.Leuven, Celestijnenlaan 200E, Box 2411, 3001 Leuven, Belgium Bruno De Vos, Research Institute for Nature and Forest, Gaverstraat 4, 9500 Geraardsbergen, Belgium Raphael Bequet, Department of Biology, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium Joris Van Acker, Laboratory of Wood Technology, Department of Forest and Water Management, Ghent University, Coupure Links 653, 9000 Ghent, Belgium Bart Muys, Division Forest, Nature and Landscape, Department of Earth and Environmental Sciences, K.U.Leuven, Celestijnenlaan 200E, Box 2411, 3001 Leuven, Belgium Journal European Journal of Forest Research Online ISSN 1612-4677 Print ISSN 1612-4669

Description:    Region of provenance is defined as an area with uniform ecological conditions where stands with similar phenotypic or genetic features are found. This study assesses the effect of differing climate conditions of eight Spanish regions of provenance of Pinus nigra Arn. subsp. salzmannii on earlywood anatomical traits measured in samples from basal discs from mature trees. Results showed that variation in wood biometry between provenances was high and more pronounced than intrapopulation variation. When comparing P. nigra with other Mediterranean pines, high intertracheid wall strength values are associated with better adaptation of pines to arid conditions. However, the intraspecific variations of this parameter in P. nigra did not follow the same pattern, due to the influence of mechanical support requirements. Trees subject to greater aridity were characterised by short tracheids, apparently resulting from their poorer growth, and high frequency of rays and ray parenchyma cells, which would allow trees to store greater amounts of starch, which is the source of metabolites invested in minimising the limitations imposed by water stress. Severe winter cold spells were strongly associated with high axial resin canal frequency and large radial resin canals, creating a powerful, preformed defence system. Increased tracheid lumen involved an increase in the size of bordered pits, favouring sap flow between tracheids, in addition to an increase in the maximum diameter of cross-field pits, favouring the flow of water and metabolites between the axial and radial systems. The high influence of region of provenance on structural variation in P. nigra shows the importance of provenance in the selection of seed origin for reforestation. Content Type Journal Article Pages 1-13 DOI 10.1007/s10342-011-0537-x Authors Luis G. Esteban, Escuela Técnica Superior de Ingenieros de Montes, Departamento de Ingeniería Forestal, Universidad Politécnica de Madrid, Ciudad Universitaria, 28040 Madrid, Spain Juan A. Martín, Escuela Técnica Superior de Ingenieros de Montes, Departamento de Silvopascicultura, Universidad Politécnica de Madrid, Ciudad Universitaria, 28040 Madrid, Spain Paloma de Palacios, Escuela Técnica Superior de Ingenieros de Montes, Departamento de Ingeniería Forestal, Universidad Politécnica de Madrid, Ciudad Universitaria, 28040 Madrid, Spain Francisco García Fernández, Escuela Técnica Superior de Ingenieros de Montes, Departamento de Ingeniería Forestal, Universidad Politécnica de Madrid, Ciudad Universitaria, 28040 Madrid, Spain Journal European Journal of Forest Research Online ISSN 1612-4677 Print ISSN 1612-4669

Description:    Effects of harrowing and fertilisation on tree growth, understory vegetation, forest floor litter and soil properties were studied in a field experiment installed in a 5-year-old first rotation eucalypt plantation. The treatments were harrowing (H), fertilisation (F), harrowing and fertilisation (HF) and a control without any treatments (C), with four replicates. Tree growth, root mass, tree nutrition status, understory vegetation, mass of forest floor litter and soil physical and chemical properties were monitored till the end of the rotation (stand was 14-year old). Effects of treatments on tree growth, root mass and timber production were not significant. Root nutrient concentration differed between treatments only few months after the beginning of the experiment, while differences regarding specific root length and area were observed during the first year. Harrowing (H and HF) led to significantly smaller biomass of understory vegetation (〈13.4 g m −2 ) than other treatments (33−61 g m −2 ) during the first 3 years, but at the end of the experiment differences were less important. Forest floor litter mass after 3 years and at the end of the experiment were similar among treatments. Soil bulk density significantly decreased by harrowing (H and HF treatments), but 16 months after treatments were similar. Although soil chemical properties were not significantly affected by treatments, a decrease in base cations occurred during the rotation period. Fertiliser application is a questionable practice under the economic point of view, whereas harrowing can reduce the fuel load only during a short period, without negative effects on productivity and soil quality. Content Type Journal Article Pages 1-14 DOI 10.1007/s10342-011-0533-1 Authors Manuel Madeira, Centro de Estudos Florestais, Instituto Superior de Agronomia – Univ. Técnica de Lisboa, 1349-017 Lisboa, Portugal António Fabião, Centro de Estudos Florestais, Instituto Superior de Agronomia – Univ. Técnica de Lisboa, 1349-017 Lisboa, Portugal Marta Carneiro, Centro de Estudos Florestais, Instituto Superior de Agronomia – Univ. Técnica de Lisboa, 1349-017 Lisboa, Portugal Journal European Journal of Forest Research Online ISSN 1612-4677 Print ISSN 1612-4669

Description:    This paper describes the development of a decision support system (DSS) for prevention planning and emergency management of forest fire events that incorporates weather data management, a geographical data viewer, a priori danger forecasting and fire propagation modeling, automatic fire detection, and optimal resource dispatching. Collection, input, storage, management, and analysis of the information rely on advanced and automated methodologies using remote sensing, GPS, digital mapping, and geographic information systems. The results included short-term dynamic fire danger indices developed for improved and realistic prevention and pre-suppression planning. An automatic fire detection technology based on infrared video was developed and successfully tested on site. Several models for understanding fire propagation on forest fires have been proposed for practical application. Additionally, a DSS was developed with the innovation of covering wildland fire hazard management entirely, providing a complete coverage of technical and administrative activities that support decision makers in real time. The DSS was tested for high fire seasons in two different sites in South Europe. Content Type Journal Article Pages 1-12 DOI 10.1007/s10342-011-0534-0 Authors Kostas Kalabokidis, Department of Geography, University of the Aegean, 81100 Mytilene, Greece Gavriil Xanthopoulos, NAGREF, Institute of Mediterranean Forest Ecosystems and Forest Products Technology, Terma Alkmanos, 11528 Athens, Greece Peter Moore, Climate, Fire and Natural Resources Consulting, 14 Jeanette Street, East Ryde, NSW 2113, Australia David Caballero, TECNOMA S.A., Area of Forest Ecosystems, Isla del Hierro 7, San Sebastián de los Reyes, 28700 Madrid, Spain George Kallos, Department of Physics, National & Kapodistrian University of Athens, 15784 Athens, Greece Juan Llorens, Department of Informatics, University Carlos III of Madrid, Leganes, 28911 Madrid, Spain Olga Roussou, Department of Geography, University of the Aegean, 81100 Mytilene, Greece Christos Vasilakos, Department of Geography, University of the Aegean, 81100 Mytilene, Greece Journal European Journal of Forest Research Online ISSN 1612-4677 Print ISSN 1612-4669

Description:    We examine whether different guilds of foragers remove seeds differentially according to seed quality (seed size and insect infestation) and seed location (habitat and microhabitat) in a mixed oak-beech forest. Video recordings indicated that the wood mouse ( Apodemus sylvaticus ) was first to encounter seeds. Foragers preferred acorns to beechnuts, large to small size and sound to infested. Nevertheless, infested seeds were removed by rodents even when sound seeds were present. Seeds that were not preferred by scatter-hoarding rodents remained longer on the ground and were more vulnerable to predation and desiccation (4% moisture loss per day). However, seeds that were removed by scatter-hoarders were moved away from their mother trees (96%) and cached individually (32%), increasing their moisture content (3% per day). Buried seeds, simulating scatter-hoarding behavior, experienced only a 17% removal after 4 months. Seed removal differences among habitats were not due to habitat attributes but to the spatial distribution of rodent-preferred microhabitats. Thus, a significant lower seed removal was observed under the tree canopy with no shrubs. However, seed removal in forest gaps with deadwood cover was not significantly different from the preferred microhabitat (under shrub cover). In pure beech forests, seed removal by rodents only occurred under Ilex aquifolium (the only perennial cover) and under woody debris. This study concludes that seed quality and seed location determine the contribution of different removers (predators vs. dispersers), their seed selection and their removal speed, leading to different seed fates which will eventually affect tree regeneration. Content Type Journal Article Pages 1-9 DOI 10.1007/s10342-011-0536-y Authors Ramón Perea, Departamento de Silvopascicultura, ETSI. Montes, Universidad Politécnica de Madrid, Ciudad Universitaria s/n, 28040 Madrid, Spain Alfonso San Miguel, Departamento de Silvopascicultura, ETSI. Montes, Universidad Politécnica de Madrid, Ciudad Universitaria s/n, 28040 Madrid, Spain María Martínez-Jauregui, Departamento de Silvopascicultura, ETSI. Montes, Universidad Politécnica de Madrid, Ciudad Universitaria s/n, 28040 Madrid, Spain María Valbuena-Carabaña, Departamento de Silvopascicultura, ETSI. Montes, Universidad Politécnica de Madrid, Ciudad Universitaria s/n, 28040 Madrid, Spain Luis Gil, Departamento de Silvopascicultura, ETSI. Montes, Universidad Politécnica de Madrid, Ciudad Universitaria s/n, 28040 Madrid, Spain Journal European Journal of Forest Research Online ISSN 1612-4677 Print ISSN 1612-4669

Description: In the future, climate models predict an increase in global surface temperature and during winter a changing of precipitation from less snowfall to more raining. Without protective snow cover, freezing can be more intensive and can enter noticeably deeper into the soil with effects on C cycling and soil organic matter (SOM) dynamics. We removed the natural snow cover in a Norway spruce forest in the Fichtelgebirge Mts. during winter from late December 2005 until middle of February 2006 on three replicate plots. Hence, we induced soil frost to 15 cm depth (at a depth of 5 cm below surface up to –5°C) from January to April 2006, while the snow-covered control plots never reached temperatures 〈 0°C. Quantity and quality of SOM was followed by total organic C and biomarker analysis. While soil frost did not influence total organic-C and lignin concentrations, the decomposition of vanillyl monomers (Ac/Ad) V and the microbial-sugar concentrations decreased at the end of the frost period, these results confirm reduced SOM mineralization under frost. Soil microbial biomass was not affected by the frost event or recovered more quickly than the accumulation of microbial residues such as microbial sugars directly after the experiment. However, in the subsequent autumn, soil microbial biomass was significantly higher at the snow-removal (SR) treatments compared to the control despite lower CO 2 respiration. In addition, the water-stress indicator (PLFA [cy17:0 + cy19:0] / [16:1ω7c + 18:1ω7c]) increased. These results suggest that soil microbial respiration and therefore the activity was not closely related to soil microbial biomass but more strongly controlled by substrate availability and quality. The PLFA pattern indicates that fungi are more susceptible to soil frost than bacteria.

Description:    Across Europe, ungulate numbers have greatly increased over the past decades, leading to increasing concerns about the ecological and economical impacts and pleas for stronger population control. However, focussing on population control only ignores other underlying factors which may enhance the wildlife–forestry conflict. I reviewed factors which shape herbivore top-down effects in natural temperate forest systems aiming at understanding how these interactions are altered in managed forests. Carnivores are important in modifying ungulate–plant interactions. They can directly influence the numbers of ungulates, but this effect is dependent on productivity and predicted to be smallest in highly productive temperate forest. Indirectly, they modify herbivore top-down effects by creating a landscape of fear. Despite the abundance of knowledge from American systems, there is a lack of knowledge on how this process might work in European systems. Next to carnivores, abiotic conditions interact with herbivory by influencing forage quality and availability. Forest gaps lead to concentration of ungulates and their effects, due to increased forage supply. Abiotic conditions also influence the response of plants following herbivory, which can be tolerated by showing increased regrowth or resistance due to chemical or physical defence. In typical managed forest systems, carnivores and abiotic conditions which shape ungulate top-down effects in natural forests are altered or absent. Human hunting might replace the direct effects of carnivores, but does not replace their indirect effects. Forestry practices also have modified herbivore–plant interactions in several ways, creating a forest with lower ungulate carrying capacity and higher sensitivity for ungulate browsing. These changes logically increase the strength of herbivore top-down effects in managed forests and increase the wildlife–forestry conflict. To reduce this conflict, aiming only at reducing wildlife numbers is predicted to have little effects when they do not coincide with habitat ameliorations. Forestry practices may therefore greatly enhance the conflict that exists between wildlife and forestry but can also be an important tool to reduce this conflict by adapting management practices that allow more natural functioning of forests systems. Content Type Journal Article Pages 1-15 DOI 10.1007/s10342-011-0523-3 Authors D. P. J. Kuijper, Mammal Research Institute, Polish Academy of Sciences, ul. Waszkiewicza 1d, 17-230 Białowieża, Poland Journal European Journal of Forest Research Online ISSN 1612-4677 Print ISSN 1612-4669

Description:    Within the EFORWOOD project, new methodological approaches to assess the sustainability impacts of forestry-wood chains (FWC) were developed by using indicators of environmental, social and economic relevance. This paper introduces and discusses the developed approach and the two main products developed in the EFORWOOD project: the Database Client and the Tool for Sustainability Impact Assessment (ToSIA), which hold, calculate and integrate the extensive information and data collected. Sustainability impact assessment (SIA) of FWCs is based on measuring and analysing environmental, economic and social indicators for all of the production processes along the value chain. The adoption of the method varies between applications and depends on the specification of the FWC in the assessment and what questions are studied. ToSIA is very flexible and can apply forest-, product-, industry- and consumer-defined perspectives. Each perspective influences the focus of the analysis and affects system boundaries. ToSIA can assess forest value chains in different geographical regions covering local, regional, national and up to the continental scale. Potential issues and scenarios can be analysed with the tool including, for example, the impacts of different forest policies on the sustainability of an FWC. This paper presents how ToSIA can be applied to solve such diverse problems and underlines this with examples from different case studies. Differences in chain set-up, system boundaries and data requirements are highlighted and experiences with the implementation of the sustainability impact assessment methods are discussed. The EFORWOOD case studies offer valuable reference data for future sustainability assessments. Content Type Journal Article Pages 1-14 DOI 10.1007/s10342-011-0483-7 Authors Marcus Lindner, European Forest Institute (EFI), Torikatu 34, 80100 Joensuu, Finland Wendelin Werhahn-Mees, European Forest Institute (EFI), Torikatu 34, 80100 Joensuu, Finland Tommi Suominen, European Forest Institute (EFI), Torikatu 34, 80100 Joensuu, Finland Diana Vötter, European Forest Institute (EFI), Torikatu 34, 80100 Joensuu, Finland Sergey Zudin, European Forest Institute (EFI), Torikatu 34, 80100 Joensuu, Finland Matias Pekkanen, European Forest Institute (EFI), Torikatu 34, 80100 Joensuu, Finland Risto Päivinen, European Forest Institute (EFI), Torikatu 34, 80100 Joensuu, Finland Martina Roubalova, Institute of Forest Ecosystem Research (IFER), Strašice 299, 33845 Strašice, Czech Republic Petr Kneblik, Institute of Forest Ecosystem Research (IFER), Strašice 299, 33845 Strašice, Czech Republic Franka Brüchert, Forstliche Versuchs- und Forschungsanstalt Baden-Württemberg (FVA), Wonnhaldestraße 4, 79100 Freiburg, Germany Erik Valinger, Department of Forest Resource Management, Swedish University of Agricultural Science (SLU), Skogsmarksgränd, 901 83 UMEÅ, Sweden Ludovic Guinard, FCBA Institut Technologique, 10 Avenue de Saint-Mandé, 75012 Paris, France Stefania Pizzirani, Forest Research, Roslin, Midlothian, EH25 9SY UK Journal European Journal of Forest Research Online ISSN 1612-4677 Print ISSN 1612-4669

Description:    Sustainability impact assessment (SIA) is a prospective, integrated assessment approach for potential impacts of policy actions. Multi-criteria analysis (MCA) can be used to facilitate a multi-indicator evaluation in this framework in order to foster rational and transparent decision-making processes for SIA. Based on the outputs of the EFORWOOD project, this paper presents an exploratory MCA to a regional forest-wood chain (FWC) in Baden–Württemberg. This assessment is based on a set of sustainability indicators at process level for a baseline year 2005, reference futures ‘A1’ and ‘B2’ following the definition of the IPCC and a bio-energy scenario implanted into the reference future ‘A1’. The indicator values were calculated by the process tool ToSIA. It is demonstrated how time steps for parts of the regional FWC (forest management, harvest and transport to the mill gate) can be evaluated, as well as the outcomes of different scenarios for a time period. For this purpose, a novel software tool, ToSIA-MCA, is used to calculate relative sustainability impact rating (SIR) based on a PROMETHEE II algorithm. Further, we performed uncertainty analysis to test the stability of ranking results in the absence of real preference information with regard to uncertainty in indicator data. By comparing different indicator weighting patterns, the sensitivity of SIR calculation was further tested. The exploratory MCA outcomes are critically evaluated against the background of assumptions, and data used in the regional case, and an outlook is given on the importance to gain stronger stakeholder involvement in real-life applications. Content Type Journal Article Pages 1-10 DOI 10.1007/s10342-011-0499-z Authors Bernhard Wolfslehner, Department of Forest and Soil Sciences, Institute of Silviculture, BOKU University of Natural Resources and Applied Life Sciences Vienna, Peter Jordan Strasse 82, 1190 Vienna, Austria Franka Brüchert, Forest Research Institute of Baden-Württemberg (FVA), Wonnhaldestr. 4, 79100 Freiburg, Germany Janine Fischbach, Institute of Forest Utilisation and Work Science, Faculty of Forest and Environmental Sciences, Albert-Ludwigs- University Freiburg, Werthmannstraße 6, 79110 Freiburg, Germany Werner Rammer, Department of Forest and Soil Sciences, Institute of Silviculture, BOKU University of Natural Resources and Applied Life Sciences Vienna, Peter Jordan Strasse 82, 1190 Vienna, Austria Gero Becker, Institute of Forest Utilisation and Work Science, Faculty of Forest and Environmental Sciences, Albert-Ludwigs- University Freiburg, Werthmannstraße 6, 79110 Freiburg, Germany Marcus Lindner, European Forest Institute (EFI), Torikatu 34, 80100 Joensuu, Finland Manfred J. Lexer, Department of Forest and Soil Sciences, Institute of Silviculture, BOKU University of Natural Resources and Applied Life Sciences Vienna, Peter Jordan Strasse 82, 1190 Vienna, Austria Journal European Journal of Forest Research Online ISSN 1612-4677 Print ISSN 1612-4669

Description: Intensive land use may affect soil properties ( e.g., decreased soil organic matter [SOM] content) and, consequently, reduce crop yields considerably. One way of counteracting the loss of SOM and stimulating plant productivity could be the use of organic residues from agro-industrial processes as bioactive products. The present study was focused on the possible effects of phenol-containing organic substances derived from agro-industrial by-products on maize ( Zea mays L.) metabolism in a pot experiment. Plants were grown for 12 d in a nutrient solution in the absence (control) or in the presence of either a cellulosolitic dry apple hydrolyzate (AP) or a dry blueberry cool extract (BB) applied at two rates (0.1 and 1 mL L –1 ). Both products increased root and leaf biomass and led to higher concentrations of macronutrients in the plant tissue. AP and BB also had a positive impact on nitrogen (N) metabolism stimulating the activity and gene expression of phenylalanine ammonia-lyase, a key enzyme of the phenylpropanoid pathway. Furthermore, both products increased leaf concentrations of phenols (+ 28% and 49% for AP and BB, respectively) and flavonoids (+ 22% and 25% for AP and BB, respectively). From our results it can be assumed that residues from agro-industry may be successfully used as bioactive products in agriculture to increase plant yield and resistance to stress conditions.

Description:    Tropospheric ozone (O 3 ) is considered to be the air pollutant relating to the decline of Fagus crenata forest in Japan. In the present study, we assessed a risk of O 3 impact on the growth of F. crenata in Japan, giving consideration to the effects associated with atmospheric nitrogen (N) deposition based on the experimental study, national monitoring data for oxidant concentration and atmospheric N deposition, and a national vegetation survey. The average and maximum O 3 -induced relative growth reduction (RG red ) of F. crenata across Japan were estimated to be 3.2 and 9.7%, respectively. Current levels of atmospheric N deposition were found to significantly affect the sensitivity of F. crenata to O 3 . When the N deposition was assumed as zero, the estimated average and maximum RG red were 2.3% and 5.7%, respectively. The inclusion of atmospheric N deposition data thus increased the estimated values for average and maximum RG red (by 38% and 71%, respectively). Our results demonstrate that a change in the sensitivity to O 3 associated with atmospheric N deposition is an important consideration in the risk assessment of O 3 impact on the growth of F. crenata in Japan. Content Type Journal Article Pages 1-10 DOI 10.1007/s10342-011-0521-5 Authors Makoto Watanabe, Research Faculty of Agriculture, Hokkaido University, Sapporo, 060-8589 Japan Masahiro Yamaguchi, 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 European Journal of Forest Research Online ISSN 1612-4677 Print ISSN 1612-4669

Description: An agricultural use of reclaimed coal-mine spoil banks is limited to nonfood crop uses and provides potential for biofuel crops. Two high-biomass crops— Galega orientalis and Helianthus tuberosus —were cultivated in a greenhouse pot experiment conducted in sterilized and nonsterile spoil bank clay. We aimed (1) to determine the possibility of reducing the applied rate of organic amendments (thus decreasing the costs of spoil-bank reclamation) and (2) to assess whether the inoculation with arbuscular mycorrhizal fungi (AMF) can improve plant growth and biomass accumulation of bioenergy crops even in nonsterile soil containing naturally occurring AMF. The spoil substrate was either unamended or treated with a mixture of composted urban waste and ligno-cellulose at a rate corresponding to 40 t ha –1 . Three native AMF isolates or three isolates from the International Bank of Glomeromycota (BEG) originating from man-made ecosystems were used for inoculation. Generally, both plant species positively responded to both mycorrhizal inoculation and organic amendment. While G. orientalis did not show any preferences towards the AMF inoculum origin in the nonsterile soil, for H. tuberosus the specific combination of organic amendment and BEG isolates resulted in highest yields of shoot biomass. The study shows that the successful planting of both tested crops requires the organic amendment. However, its dosage can be substantially reduced. The effectiveness of mycorrhizal inoculation can vary for the combination of plant species and the origin of the applied AMF.

Description: Iodine is an essential element in the human diet, and iodine deficiency is a significant health problem. No attempts to increase iodine content in plant-derived food (biofortification) have so far been particularly effective. We studied iodine uptake in tomato ( Solanum lycopersicum L.) to evaluate whether it is possible to increase the iodine concentration in its fruits. Iodine translocation and storage inside tomato tissues were studied using radioactive iodine. Potassium iodide was also supplied at different concentrations to tomato plants to evaluate the resulting iodide concentration both in the vegetative tissues and the fruits. The results indicate that iodine was taken up better when supplied to the roots using hydroponically grown plants. However, a considerable amount of iodine was also stored after leaf treatment, suggesting that iodine transport through phloem also occurred. We found that tomato plants can tolerate high levels of iodine, stored both in the vegetative tissues and fruits at concentrations that are more than sufficient for the human diet. We conclude that tomato is an excellent crop for iodine-biofortification programs.

Description: Citrus established in calcareous soils can be affected by iron (Fe)-deficiency chlorosis which limits yield and the farmers' income. The degree of deficiency depends on the rootstock, but the resistance to Fe chlorosis still requires further investigation. To study physiological parameters of citrus rootstocks that could be used to evaluate resistance to Fe deficiency, plants of Troyer citrange ( Citrus sinensis L. Osb. × Poncitrus trifoliata L. Raf.), Carrizo citrange, Volkamer lemon ( Citrus volkameriana Ten. & Pasq.), alemow ( Citrus macrophylla Wester), and sour orange ( Citrus aurantium L.) were grown in nutrient solutions with 0, 5, 10, 15, or 20 μM Fe. For each rootstock, plant height, root and shoot dry weights, and concentration of Fe in the shoots and roots were measured at the end of the experiment. Chlorophyll (CHL) concentration was estimated throughout the experimental period using a portable CHL meter (SPAD-502) calibrated for each rootstock. At the end of the experiment, CHL fluorescence parameters were measured in each rootstock with a portable fluorimeter. Maximal and variable fluorescence values indicated that the photochemistry of Troyer was more affected by a low concentration of Fe in the nutrient solution than that of other rootstocks. To compare rootstocks, the absolute CHL concentration was converted into relative yield by employing a scaling divisor based on the maximum value of total CHL in plants without Fe-deficiency symptoms. Exponential models were developed to determine the minimum Fe concentration in nutrient solution required to maintain leaf CHL at 50% of the maximum CHL concentration (IC50). Models were also developed to assess the period of time the rootstocks were able to grow under Fe-stress conditions before they reached IC50. Volkamer lemon and sour orange needed the lowest Fe concentration (between 4 and 5 μM Fe) to maintain IC50, and Troyer citrange had the highest Fe requirement (14 μM Fe). Citrus macrophylla and Carrizo citrange required 7 and 9 μM of Fe, respectively. Similarly, Volkamer lemon and sour orange rootstocks withstood more days under total Fe depletion or with a low concentration of Fe (5 μM Fe in nutrient solution) until they reached IC50, compared to the other rootstocks. The approach used led to a classification of the rootstocks into three categories, regarding their internal tolerance to Fe chlorosis: resistance (sour orange and Volkamer lemon), intermediate resistance (C . macrophylla and Carrizo citrange), and reduced resistance (Troyer citrange).

Description: Trees interact in a complex manner with soils: they recycle and redistribute nutrients via many ecological pathways. Nutrient distribution via leaf litter is assumed to be of major importance. Beech is commonly known to have lower nutrient concentrations in its litter than other hardwood tree species occurring in Central Europe. We examined the influences of distribution of beech ( Fagus sylvatica L.), ash ( Fraxinus excelsior L.), lime ( Tilia cordata Mill. and T. platyphyllos Scop.), maple ( Acer spp. L.), and clay content on small-scale variability of pH and exchangeable Ca and Mg stocks in the mineral soil and of organic-C stocks in the forest floor in a near-natural, mature mixed deciduous forest in Central Germany. The soil is a Luvisol developed in loess over limestone. We found a positive effect of the proportion of beech on the organic-C stocks in the forest floor and a negative effect on soil pH and exchangeable Ca and Mg in the upper mineral soil (0 to 10 cm). The proportion of ash had a similar effect in the opposite direction, the other species did not show any such effect. The ecological impact of beech and ash on soil properties at a sample point was explained best by their respective proportion within a radius of 9 to 11 m. The proportion of the species based on tree volume within this radius was the best proxy to explain species effects. The clay content had a significant positive influence on soil pH and exchangeable Ca and Mg with similar effect sizes. Our results indicate that beech, in comparison to other co-occurring deciduous tree species, mainly ash, increased acidification at our site. This effect occurred on a small spatial scale and was probably driven by species-related differences in nutrient cycling via leaf litter. The distribution of beech and ash resulted not only in aboveground diversity of stand structures but also induced a distinct belowground diversity of the soil habitat.

Description: Several chemical and microbial properties of mine soils need to be measured for comprehensive assessment of the reclamation success. The objective of this study was to evaluate the ability of NIR spectroscopy to predict organic C (C org ), total N (N t ), and several microbial properties of mine soils reclaimed for forestry. Soils samples ( n = 154) were collected at two reclaimed areas in central and S Poland, and their spectra in the NIR region (including the visible range, 400–2500 nm) were recorded. A half of the samples was used to develop calibration equations, and another half was used for validation. The modified partial least squares regression was applied to build calibration equations using the whole spectrum (0 to 2nd derivative). The best predictions were obtained for C org and N t (ratio of standard deviation to standard error of prediction in the validation stage [RPD] = 3.4 and 4.1; the regressions coefficients [ a ] of linear regression [measured against predicted values] = 0.94 and 0.96; correlation coefficients [ r ] = 0.96 and 0.97, respectively). Very well predictive models applicable for quantitative measurements were obtained also for microbial biomass, basal respiration, and the activities of dehydrogenase and acid phosphatase (RPD = 2.3–2.5, a = 0.90–0.99, r = 0.90–0.92). Prediction of urease activity was slightly worse (RPD = 2.1, a = 0.88, r = 0.87) but sufficient for rough estimation. The obtained results indicated the ability of NIR spectroscopy to predict complex soil microbial properties. Therefore, application of this analytical method may improve the assessment of recovery of microbial functions in reclaimed post-mining barrens.

Description: Several algorithms exist for the calibration procedures of near-infrared spectra in soil-scientific studies, but the potential of a genetic algorithm (GA) for spectral feature selection and interpretation has not yet been sufficiently explored. Objectives were (1) to test the usefulness of near-infrared spectroscopy (NIRS) for a prediction of C and N from char and forest-floor Oa material in soils using either a partial least squares (PLS) method or a GA-PLS approach and (2) to discuss the mechanisms of GA feature selection for the examined constituents. Calibration and validation were carried out for measured reflectance spectra in the visible and near-IR region (400–2500 nm) on an existing set of 432 artificial mixtures of C-free soil, char (lignite, anthracite, charcoal, or a mixture of the three coals), and forest-floor Oa material. For all constituents (total C and N, C and N from all coals and from the Oa material, C derived from mixed coal, charcoal, lignite, and anthracite), the GA-PLS approach was superior over the full-spectrum PLS method. The RPD values (ratio of standard deviation of the laboratory results to standard error of prediction) ranged from 2.4 to 5.1 in the validation and indicated a better category of prediction for three constituents: “approximate quantitative” instead of a “distinction between high and low” for C derived from mixed coal and “good” instead of “approximate quantitative” for C and N derived from all coals. Overall, this study indicates that the approach using GA may have a greater potential than the PLS method in NIRS.

Description: Several genes in the aspen genome have been modified to generate stem wood with lower lignin content and an altered lignin composition. Lower lignin in wood reduces the time and energy required for pulping. Further, this modification can also increase the allocation of photosynthate to cellulose and total biomass production, potentially increasing CO 2 -sequestration capacity. However, widespread planting of trees with altered lignin content and composition could alter soil organic-C dynamics in complex ways. To further examine the effects of altered lignin biosynthesis on plant growth and accrual of soil organic C (SOC), we conducted a repeated greenhouse study with four lines of transgenic aspen ( Populus tremuloides Michx.) and one wild-type (control) aspen. Accrual of aspen-derived SOC was quantified by growing aspen trees (C3 plants) in C4 soil and measuring changes in the natural abundance of δ 13 C. We measured plant growth, biomass, and C content and combined these data with SOC measurements to create C budgets for the plant mesocosms. Lignin modifications resulted in differences in the accrual of aspen-derived SOC and total mesocosm C, primarily due to differences in biomass between genetically modified lines of aspen. One genetic alteration (low lignin, line 23) was able to perform similarly or better than the wild-type aspen (control, line 271) without altering SOC. Alterations in lignin structure (S : G ratios) had negative effects on biomass production and SOC formation. The addition of new (aspen-derived) SOC was proportional to the loss of existing SOC, evidence for a priming effect. The pool of new SOC was related to total plant biomass, suggesting that the effects of lignin modification on SOC are driven by changes in plant growth.

Description:    Mountain birch ( Betula utilis ) is the most important treeline species in alpine forests of southwestern China. In order to understand the effects of future warming on treeline birch, this study was conducted to examine the effects of experimental warming on leaf phenology, growth and gas exchange of B. utilis saplings using the open top chamber (OTC) method in a treeline ecotone of eastern Tibetan Plateau. The OTCs enhanced daily mean air temperature by 2.9 K throughout the growing season. Conversely, soil moisture within the OTCs on average declined by 3% over the experimental period. Experimental warming did not affect the timing of bud break, although treeline birch saplings growing in the OTCs manifested later leaf abscission, resulting in longer leaf life span. Artificial warming significantly accelerated the leaf and shoot growth rates of treeline birch saplings, resulting in larger leaf area and longer shoot elongation late in the growing season. Moreover, experimental warming significantly reduced the leaf fluctuating asymmetry (FA) and tended to increase specific leaf area (SLA). Moreover, elevated temperatures significantly enhanced the transpiration rate ( E ), stomatal conductance ( g s ), maximum net assimilation rate ( A max ), dark respiration rate ( R d ) and apparent quantum yield (AQY) but did not influence the light compensation point (LCP) and light saturation point (LSP) of treeline birch saplings. Taken together, our results indicated that short-term experimental warming markedly altered structural/functional leaf traits and enhanced photosynthetic capacity of treeline birch saplings; such positive responses in treeline birch would be favorable for the growth of this species under future warmer world. Content Type Journal Article Pages 1-9 DOI 10.1007/s10342-011-0554-9 Authors Zhenfeng Xu, Institute of Ecological Forestry, Sichuan Agricultural University, Chengdu, 611830 China Tingxing Hu, Faculty of Forestry, Sichuan Agricultural University, Ya’an, 625014 China Yuanbin Zhang, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041 China Journal European Journal of Forest Research Online ISSN 1612-4677 Print ISSN 1612-4669

Description:    The objectives of this study were to describe and quantify Aleppo pine aerial primary growth processes and to assess their relationships with climate. Primary growth (branch length growth, branching rate, polycyclism, needle number and size, fruiting), i.e. crown development and reproduction, was reconstructed for the last 16 years in Mediterranean France. From 1998 to 2007, climate has been far hotter and drier than normal in South-eastern France. All variables related to crown development and fruiting, as well as radial growth, significantly declined after 2003 heat wave and during repeated droughts from 2004 to 2007. A partial recovery of most parameters occurred from 2008 to 2010 on vigorous branches while frail branches showed less improvement. The limited crown development during unfavourable years may significantly hold back tree potential photosynthetic biomass for several following years and contribute to a slower than expected recovery of tree growth or to delayed die-back. Content Type Journal Article Category Original Paper Pages 1-13 DOI 10.1007/s10342-011-0565-6 Authors François Girard, CEMAGREF, Ecosystèmes Méditerranéens et Risques, 3275 Route de Cézanne CS 40061, 13182 Cedex 5, Aix en Provence, France Michel Vennetier, CEMAGREF, Ecosystèmes Méditerranéens et Risques, 3275 Route de Cézanne CS 40061, 13182 Cedex 5, Aix en Provence, France Frédéric Guibal, IMEP, Faculté des Sciences de St Jérôme, Avenue Escadrille Normandie-Niemen, Boite 441, 13397 Marseille, Cedex 20, France Christophe Corona, IMEP, Faculté des Sciences de St Jérôme, Avenue Escadrille Normandie-Niemen, Boite 441, 13397 Marseille, Cedex 20, France Samira Ouarmim, CEMAGREF, Ecosystèmes Méditerranéens et Risques, 3275 Route de Cézanne CS 40061, 13182 Cedex 5, Aix en Provence, France Asier Herrero, Departamento de Ecología, Facultad de Ciencias, Campus de Fuentenueva, Universidad de Granada, 18071 Granada, Spain Journal European Journal of Forest Research Online ISSN 1612-4677 Print ISSN 1612-4669

Description:    Due to high variation in forest communities, forest structure and the fragmentation of the forested area in Central Europe, satellite-based forest inventory methods have to meet particularly high-quality requirements. This study presents an innovative method to combine official forest inventory information at stand level with multidate satellite imagery using a spatially adaptive classification approach for producing wall-to-wall forest cover maps of important tree species and management classes across multiple ownership regions in a heterogeneous low mountain range in Germany. The classification approach was applied to a 5,200-km 2 area (about 2,080 km 2 of forest land, mostly mixed forests) located in the Eifel mountain range in Central Europe. In comparison with conventional classifiers, our results demonstrate a significant increase in classification accuracy in the order of 12%. The method was tested with ASTER images but holds the potential to be used for regular state forest inventories based on standard and novel earth observation data supplied for instance from the SPOT-5 and RapidEye sensors. Content Type Journal Article Category Original Paper Pages 1-19 DOI 10.1007/s10342-011-0577-2 Authors Johannes Stoffels, Environmental Remote Sensing and Geoinformatics, University of Trier, Trier, Germany Sebastian Mader, Environmental Remote Sensing and Geoinformatics, University of Trier, Trier, Germany Joachim Hill, Environmental Remote Sensing and Geoinformatics, University of Trier, Trier, Germany Willy Werner, Department of Geobotany, University of Trier, Trier, Germany Godehard Ontrup, Forest Management Planning, National Forests Rhineland-Palatinate, Koblenz, Germany Journal European Journal of Forest Research Online ISSN 1612-4677 Print ISSN 1612-4669

Description: Wild barley ( Hordeum sp. ) germplasm is rich in genetic diversity and provides a treasure trove of useful genes for crop improvement. We carried out a comprehensive program combining short-term hydroponic screening via hematoxylin-staining of root-regrowth procedure and filter paper–based evaluation of diverse germplasm in response to Al/acid stress using 105 annual Tibetan wild barley and 45 cultivated barley genotypes. Root elongation among the 105 Tibetan wild barley genotypes varied significantly after Al exposure, ranging from 62.9% to 80.0% in variation coefficients and 4.35 to 4.45 in diversity index. These genotypic differences in Al resistance were fairly consistent in both the hydroponic and filter paper–based evaluations: XZ16, XZ166, and XZ113 were selected as Al-resistant genotypes, and XZ61, XZ45, and XZ98 as Al-sensitive wild genotypes. Furthermore, significantly lower Al concentrations in roots and shoots were detected in the three selected Al-resistant genotypes than in the three sensitive genotypes in the filter paper–based experiment. Meanwhile, XZ16 was the least affected by Al toxicity in regard to reduced SPAD value (chlorophyll meter readings), plant height, root length, dry biomass, tillers per plant, and chlorophyll fluorescence (Fv/Fm) in the long-term hydroponic experiment compared with the Al-resistant cultivated barley cv. Dayton, while XZ61 had the severest stress symptoms.

Description: Simplified algebraic equations are derived to calculate directly the Brooks and Corey model parameters using data obtained from one-step outflow experiments and saturated hydraulic conductivity. The suggested method has been demonstrated only for horticultural substrates and is verified experimentally for four substrates with satisfactory agreement of the results.

Description: Fine roots from the soil archive of the Swedish National Forest Soil Inventory, collected in 1964, 1972, 1985, and 1998, were analyzed for 14 C contents. Two different methods of estimating residence time were compared. Residence time of root C was estimated to be 8 y using a steady state 1-pool model.

Description: Appropriate management of P from slurry can increase crop production and decrease nutrient loss to water bodies. The present study examined how the application of different size fractions of dairy slurry influenced the quantity and composition of P leached from grassland in a temperate climate. Soil blocks were amended (day 0 = start of the experiment) with either whole slurry (WS), the 〉 425 μm fraction (coarse slurry fraction, CSF), the 〈 45 μm slurry fraction (fine liquid slurry fraction, FLF), or not amended, i.e., the control soil (CON). Deionized water was added to the soil blocks to simulate six sequential rainfall events, equivalent to 250 mm (day 0.2, 1.2, 4.2, 11.2) or 500 mm of rainfall (day 18.2 and 25.2), with leachates collected the following day. The results showed that total dissolved P (TDP), dissolved reactive P (DRP), dissolved unreactive P (DUP), orthophosphate, phosphomonoester, and pyrophosphate concentrations generally decreased with the increasing number of simulated rain events. Total dissolved P was leached in the following order WS 〉 FLF ≈ CSF 〉 CON. Dissolved organic C was correlated with TDP, DRP, and DUP in leachates of all treatments. The highest concentrations of dissolved phosphomonoesters and pyrophosphate (147 μg P L –1 and 57 μg P L –1 , respectively) were detected using solution 31 P-NMR spectroscopy in the WS leachates. Overall, there were significant differences observed between slurry treatments ( e.g., relative contributions of inorganic P vs. organic P of dissolved P in leachates). Differences were independent from the rate at which slurry P was applied, because the highest dissolved P losses per unit of slurry P applied were measured in the FLF, i.e., the treatment that received the smallest amount of P. We conclude that the specific particle-size composition of applied slurry influences dissolved P losses from grassland systems. This information should be taken in account in farm-management approaches which aim to minimizing dissolved slurry P losses from grassland systems.

Description:    Aging in trees implies a progressive reduction in the growth rate, related to a shortening of the growing period and changes in the photosynthetic capability and efficiency. These changes may continue during the old-growth life stages following the juvenile phase and are reflected in tree-ring properties such as growth increment, density or stable isotopes. We studied possible climate age effects in time series of several tree-ring parameters (ring width, wood density and stable carbon and oxygen isotopes) of mature individuals from two age groups of Pinus uncinata and P. nigra at two locations in Spain. The aim was to test whether age differences in trees in the old-growth life stages could lead to diverging climate responses. The results show some differences in response to climate between age groups at a monthly level, but most of these divergences are not significant for seasonal climate variables. Regardless of the age group, the main limiting climate factors constrained tree growth equally. Although our findings do not support the idea of an age-dependent response to climate that may lead to inaccurate climate reconstructions, further studies using tree-ring density and stable isotope series are urgently needed to verify the current results. Content Type Journal Article Category Original Paper Pages 1-12 DOI 10.1007/s10342-011-0566-5 Authors Isabel Dorado Liñán, Departament d’Ecologia, Universitat de Barcelona, Barcelona, Spain Emilia Gutiérrez, Departament d’Ecologia, Universitat de Barcelona, Barcelona, Spain Ingo Heinrich, German Centre for Geosciences, Climate Dynamics and Landscape Evolution, Potsdam Dendro Laboratory, Potsdam, Germany Laia Andreu-Hayles, Tree-Ring Laboratory, Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY, USA Elena Muntán, Departament d’Ecologia, Universitat de Barcelona, Barcelona, Spain Filipe Campelo, Departament d’Ecologia, Universitat de Barcelona, Barcelona, Spain Gerhard Helle, German Centre for Geosciences, Climate Dynamics and Landscape Evolution, Potsdam Dendro Laboratory, Potsdam, Germany Journal European Journal of Forest Research Online ISSN 1612-4677 Print ISSN 1612-4669

Description:    World-wide deforestation is being reversed in Mediterranean continental areas, where abandonment of traditional practises favours the expansion of valuable habitats, like Juniperus thurifera woodlands. We hypothesised that pre-existing trees facilitate establishment in expanding woodlands, whereas in mature woodlands, competition leads to patch disaggregation. We compared the imprint of these processes on growth, demographic and spatial structure of expanding and mature J. thurifera woodlands. We selected plots where we geopositioned, aged and quantified the morphological characteristics of all trees. In the mature woodland, trees arranged in clumps and randomly in the expanding woodland. Competition negatively affected growth, was greater in the mature woodland and led to disaggregation of juvenile clumps. Differences in growth between the mature and the expanding woodland disappeared in climatically unfavourable years, suggesting that adverse climate constrains growth more in expanding than in mature woodlands. We suggest that change in the dispersal agents and a decrease of facilitation underlay differences in spatial patters between the expanding and the mature woodland. Observed effective recruitment in less than 30 years into the expanding woodland evidenced that propagule arrival and sapling survival do not constrain woodland expansion. Furthermore, growth of juveniles established in these new areas is favoured by reduced intra-specific competition. However, we expect growth in expanding woodlands to be negatively impacted by climate change. We conclude that under current global change scenario, conservation of J. thurifera woodlands is favoured by changes in land use, but greater frequency and severity of drier than usual episodes could hamper natural reforestation. Content Type Journal Article Category Original Paper Pages 1-11 DOI 10.1007/s10342-011-0569-2 Authors Teresa E. Gimeno, Laboratorio Internacional de Cambio Global (LINC-Global), Museo Nacional de Ciencias Naturales, MNCN, CSIC, Serrano 115 dpdo., 28006 Madrid, Spain Beatriz Pías, Laboratorio Internacional de Cambio Global (LINC-Global), Museo Nacional de Ciencias Naturales, MNCN, CSIC, Serrano 115 dpdo., 28006 Madrid, Spain Jesús Martínez-Fernández, Laboratorio Internacional de Cambio Global (LINC-Global), Museo Nacional de Ciencias Naturales, MNCN, CSIC, Serrano 115 dpdo., 28006 Madrid, Spain David L. Quiroga, Laboratorio Internacional de Cambio Global (LINC-Global), Museo Nacional de Ciencias Naturales, MNCN, CSIC, Serrano 115 dpdo., 28006 Madrid, Spain Adrián Escudero, Departamento de Biología y Geología, ESCET, Universidad Rey Juan Carlos, Tulipán s/n, 28933 Móstoles, Spain Fernando Valladares, Laboratorio Internacional de Cambio Global (LINC-Global), Museo Nacional de Ciencias Naturales, MNCN, CSIC, Serrano 115 dpdo., 28006 Madrid, Spain Journal European Journal of Forest Research Online ISSN 1612-4677 Print ISSN 1612-4669

Description:    Geographically structured tree-ring networks are needed to fully understand the spatiotemporal variability in climatic sensitiveness of trees and to study their future responses to global warming. We aim to identify the spatially constrained structure of radial-growth patterns of the Spanish juniper ( Juniperus thurifera L.) and to assess whether their climate–growth responses were unstable during the late twentieth century. Tree–ring width chronologies were built for 13  J. thurifera stands in Spain using dendrochronological methods and related to monthly climatic data. Sites were grouped according to their growth patterns using hierarchical cluster analysis. The relationships among geographical, climatic and stand features and their influence on radial growth were evaluated using redundancy analysis. The climate–growth relationships and their temporal stability were assessed using Pearson’s and moving bootstrapped correlations, respectively. Stands formed three geographical groups according to their high-frequency growth variation: North West and Centre, North East and South East. We found that J. thurifera radial-growth patterns depended on geographical and climatic factors, but not on the stand structure, and responded to a northwest–southeast gradient of decreasing rainfall and influence of Atlantic Westerlies and Mediterranean cyclonic activity. The positive response to June precipitation was unstable during the late twentieth century and started earlier in populations from western mesic sites than in eastern xeric sites. This pattern may be related to either decreasing water availability in western than in eastern sites or the resilience of J. thurifera growth from xeric sites in response to the increasing summer aridity. Content Type Journal Article Category Original Paper Pages 1-13 DOI 10.1007/s10342-011-0564-7 Authors Lucía DeSoto, Centro de Ecologia Funcional, Departamento de Ciências da Vida, Universidade de Coimbra, Apdo. 3046, 3001–456 Coimbra, Portugal Jesús Julio Camarero, ARAID, Instituto Pirenaico de Ecología (CSIC), Avda. Montañana 1005, 50080 Zaragoza, Spain José Miguel Olano, Área de Botánica, Departamento de Ciencias Agroforestales, EUI Agrarias, Universidad de Valladolid, Los Pajaritos s/n, 42004 Soria, Spain Vicente Rozas, Misión Biológica de Galicia (MBG-CSIC), Apdo. 28, 36080 Pontevedra, Spain Journal European Journal of Forest Research Online ISSN 1612-4677 Print ISSN 1612-4669

Description: Several methods are used for the extraction of soil solution. The objective of this study was to find out to what extent the different extraction methods yield complementary or equivalent information. Soil solutions were sampled once at 10 different forest sites in Germany, with 4 sampling points per site, using 5 different extraction methods. Concentrations of the major ions in the 1:2 extracts and the equilibrium soil-pore solutions (obtained from percolation of field-fresh soil cores) were generally lower than in desorption solutions, suction-cup solutions, and saturation extracts. Surprisingly, the latter three methods generally yielded equivalent results. However, possible systematic differences between these methods could have been masked by the high small-scale spatial variability within the sites.

Description: A standard and a high manganese (Mn) level (10 and 160 μM) were combined with a standard and a high zinc (Zn) level (4 and 64 μM) in the nutrient solution supplied to cucumber in closed-cycle hydroponic units to compensate for nutrient uptake. The concentrations of all nutrients except Mn and Zn were identical in all treatments. The objectives of the experiment were to establish critical Zn and Mn levels in both nutrient solutions and leaves of cucumber grown hydroponically, to assess the impact of gradual Zn and/or Mn accumulation in the external solution on nutrient uptake and gas exchange, and to find whether Mn and Zn have additive effects when the levels of both ions are excessively high in the root zone. The first symptoms of Mn and Zn toxicity appeared when the concentrations of Mn and Zn in the leaves of cucumber reached 900 and 450 mg kg –1 in the dry weight, respectively. Excessively high Mn or/and Zn concentrations in the leaves reduced the fruit biomass production due to decreases in the number of fruits per plant, as well as the net assimilation rate, stomatal conductance, and transpiration rate, but increased the intercellular CO 2 levels. Initially, the Mn or Zn concentrations in the recirculating nutrient solution increased rapidly but gradually stabilized to maximal levels, while the corresponding concentrations in the leaves constantly increased until the end of the experiment. The uptake of Mg, Ca, Fe, and Cu was negatively affected, while that of K and P remained unaffected by the external Mn and Zn levels. The combination of high Mn and Zn seems to have no additive effects on the parameters investigated.

Description: A pot experiment with wheat plants was carried out to study how late application of nitrogen (N) fertilizer affects the use of pre-anthesis N reserves during the grain-filling period. Increasing doses of N fertilizer were applied (0, 40, and 52 mg N plant –1 ), either in two amendments (growth stages GS20 and GS30, according to Zadoks scale) or in three amendments (GS20, GS30, and GS37). The experiment was arranged in a complete randomized three-block design with 129 plants per treatment. The plants were watered daily, harvested every 2 d between anthesis and maturity, and were separated into roots, leaf sheaths, leaf blades, and ears for further N determination. Grain N concentration improved due to a late N application in GS37 by 14% (higher N dose) and by 7% (further splitting the same N-fertilizer dose, respectively). The higher the N-fertilizer dose applied, the greater was the amount of pre-anthesis reserves in vegetative organs, these reserves became later available for remobilization. Although splitting the same N dose in three amendments did not increase the N reserves, these reserves were more efficiently remobilized allowing an improvement in grain N concentration. The fertilizer management did not change the temporary pattern of N accumulation in the ear, but did induce a change in the amount of N remobilized and in the contribution of each organ (root, leaf sheath, leaf blade) to this remobilization. Late N amendment allowed a greater N availability of leaf blades and ear N reserves (from 20% up to 26% and from 19% up to 22%, respectively) for remobilization towards the grain, decreasing the root contribution from 28% down to 15%, while the contribution of leaf sheaths was maintained around 35% irrespective of the N applied.

Description: Flooded rice ( Oryza sativa L.) may contain high arsenic (As) concentrations compared to other grain crops. For the development of measures to reduce the As concentration of rice grains, knowledge about the mobility of As within the rice plant is required. Therefore, to investigate the mobilization of As within the plant, rice was grown in nutrient solution and exposed to As either before flowering, after flowering, or continuously until maturity. Furthermore, rice was grown in four soils under greenhouse and field conditions and the time course of As accumulation in grains during the grain-filling period was investigated. When grown in nutrient solution, As removal at flowering did not reduce As concentrations in polished rice compared to plants supplied with As continuously or after flowering. Plants that received As only after flowering had the same As concentrations in shoot and bran as plants receiving As only before flowering. However, continuous As supply resulted in doubling of As concentrations in both plant parts. In contrast to grain and shoot, the As concentration in the root decreased after As removal compared to the treatments receiving As only after flowering or continuously. The observations indicate that As was mobilized from root or shoot to the grain and that it was accumulated in the grain, although it was not available in nutrient solution during the grain-filling period. In soil experiments, the 1000-grain weight increased up to 2 weeks before harvest in the field as well as in the greenhouse. The As concentration in rice grain was constant during the whole grain-filling period. It was at a similar level under field and greenhouse conditions, and its variation among soils was in the same order indicating that soil was the decisive factor for As concentration in grains. Our results suggest that temporary cultural measures during the cultivation period, for example drainage, might be ineffective because of the mobilization capacity within the rice plant. Moreover, harvest before final maturity of grains would not reduce the As concentration since it remained constant during the grain-filling period.

Description:    The pinewood nematode (PWN), Bursaphelenchus xylophilus , the causal agent of the pine wilt disease, has been detected in several regions of Portugal affecting Pinus pinaster , a coniferous species of a great economic value. The nematodes, migrating through resin canals and feeding on parenchyma cells, induce rapid metabolic changes in ray parenchyma cells, cavitation areas, and denaturation and necrosis of parenchyma and cambial cells. To understand how anatomic changes and biochemical incidences of tree defense reactions affect the technological parameters of the wood, the gross calorific value (GCV) and chemical composition of PWN-infected and -uninfected P. pinaster wood were evaluated. The GCV was determined using Parr 6300 Automatic Isoperibol Calorimeter, and chemical composition analysis was performed by determining the contents of carbon, hydrogen, nitrogen, sulfur and Ash on complete and instant oxidation of samples by “flash” combustion. The Student’s t test with Welch correction was used for statistical data analysis. The difference between the GCV and chemical composition for PWN-infected and -uninfected P. pinaster wood was statistically significant for the GCV and for hydrogen and nitrogen contents. The carbon, oxygen, sulfur and Ash contents did not differ statistically. The GCV of PWN-infected wood varied between the highest value of hardwood and the lowest value of softwood. This interdisciplinary study stresses the important technological and economic aspects, namely the impact of PWN on wood properties and the suitability of infected P. pinaster wood for use in the wood-processing and energy industries. Content Type Journal Article Category Original Paper Pages 1-9 DOI 10.1007/s10342-011-0574-5 Authors Valeria Reva, Centre of Forest Fire Studies, Association for the Development of Industrial Aerodynamics (CEIF/ADAI), Rua Pedro Hispano, no 12, 3031-601 Coimbra, Portugal Luís Fonseca, IMAR-CMA, Department of Life Sciences, University of Coimbra, 3004-517 Coimbra, Portugal José L. Lousada, CITAB, Centre for Research and Technology of Agro-Environment and Biological Sciences, UTAD, Quinta dos Prados Apartado, 1013-5001-801 Vila Real, Portugal Isabel Abrantes, IMAR-CMA, Department of Life Sciences, University of Coimbra, 3004-517 Coimbra, Portugal Domingos X. Viegas, Centre of Forest Fire Studies, Association for the Development of Industrial Aerodynamics (CEIF/ADAI), Rua Pedro Hispano, no 12, 3031-601 Coimbra, Portugal Journal European Journal of Forest Research Online ISSN 1612-4677 Print ISSN 1612-4669

Description: Challenges in implementing sustainability impact assessment of forest wood chains Content Type Journal Article Category Editorial Pages 1-5 DOI 10.1007/s10342-011-0571-8 Authors Kaj Rosén, The Forest Research Institute of Sweden, Uppsala Science Park, 75183 Uppsala, Sweden Marcus Lindner, European Forest Institute, Torikatu 34, 80100 Joensuu, Finland Gert-Jan Nabuurs, European Forest Institute, Torikatu 34, 80100 Joensuu, Finland Piotr Paschalis-Jakubowicz, Faculty of Forestry, Department of Forest Utilization, Warsaw University of Life Sciences (SGGW), ul. Nowoursynowska 159, 02-776 Warszawa, Poland Journal European Journal of Forest Research Online ISSN 1612-4677 Print ISSN 1612-4669

Description:    Although pollen dispersal has been extensively studied in trees, parameters influencing between-population variation are still poorly understood. In this study, we conducted paternity analyses on open-pollinated seeds in four natural populations of wild cherry ( Prunus avium ) with contrasting density and clonal propagation, using eight microsatellite loci and one self-incompatibility system locus. We also measured four quantitative traits and spatial positions as potential correlates of reproductive success. Levels of polyandry differed among populations and 30% of the seed families exhibited unequal paternal contributions, suggesting variation in reproductive success rather than variation in mate availability. Mating occurred preferentially among neighbours in all populations, suggesting that it is a common pattern in wild cherry and probably results from pollinator behaviour. Paternal success was positively correlated with diameter at breast height, as indicated in previous studies and tree dominance only resulted in higher paternal success in low density plots. Mating patterns were thus also affected by both density and tree size. Large-scale studies are needed to disentangle relative influences of these factors on the mating system and pollination success. Content Type Journal Article Category Original Paper Pages 1-15 DOI 10.1007/s10342-011-0576-3 Authors Céline Jolivet, Institute of Forest Genetics, Johann Heinrich von Thünen Institut (vTI), Sieker Landstrasse 2, 22927 Grosshansdorf, Germany Aki M. Höltken, Department of Wood Science, World Forestry, University of Hamburg, Leuschnerstrasse 91, 21031 Hamburg, Germany Heike Liesebach, Institute of Forest Genetics, Johann Heinrich von Thünen Institut (vTI), Sieker Landstrasse 2, 22927 Grosshansdorf, Germany Wilfried Steiner, Nordwestdeutsche Forstliche Versuchsanstalt Abteilung Waldgenressourcen, Prof.-Oelkers-Str. 6, 34346 Hann. Münden, Germany Bernd Degen, Institute of Forest Genetics, Johann Heinrich von Thünen Institut (vTI), Sieker Landstrasse 2, 22927 Grosshansdorf, Germany Journal European Journal of Forest Research Online ISSN 1612-4677 Print ISSN 1612-4669

Description:    Soil loss rates currently recorded in forests are very low. Nevertheless, that may not be the case during stand installation and early tree growth stage, when soil is disturbed and scarcely covered. Site preparation techniques, performed to improve soil conditions for plant growth, should help reducing this erosion potential. In this study, several site preparation techniques were applied prior to installing a mixed stand ( Pseudotsuga mensiezii and Castanea sativa ) and a subsequent monitoring scheme of run-off and soil loss ran for 2 years in order to compare their effectiveness for erosion control. The experimental area, near Macedo de Cavaleiros, NE Portugal, at 700 m elevation, with annual means of 656 mm rainfall and 12°C temperature, has Mediterranean climatic conditions. Experimental design comprised three blocks, corresponding to different topographical positions (near flat plateau, moderate slope shoulder and steep mid-slope), where eight treatments were randomly distributed in plots with 375 m 2 area: (1) Original soil control (no intervention on the original abandoned field); (2) No subsoiling, no ploughing, plantation with hole digger; (3) Subsoiling over the whole area, with covering shovel; (4) No subsoiling, contour bunds shaped by two plough passes; (5) Subsoiling in future plantation rows, contour bunds shaped by two plough passes; (6) Subsoiling over the whole area, contour bunds shaped by two plough passes; (7) Subsoiling over the whole area, contour ploughing over the whole area; and (8) Potential erosion (subsoiling over the whole area, ploughing downhill). Sediment and water exported from small plots (2.5 m 2 average area), two replicates per treatment and block, were collected after each rainfall erosion event, in a total of 21, summing 1,876-mm precipitation in 2 years. Mean annual run-off and soil loss in the original soil were 3.4 mm and 11.6 g m −2 , respectively. In treatments 2–7, values were higher 3–7 times, for run-off, and 5–12 times, for soil loss. Potential erosion averages 2.3 t ha −1 year −1 . Soil loss and run-off tend to increase with tillage intensity associated with site preparation technique, even though average two-year losses, in all cases, are below tolerable rates. Soil loss and run-off rates decreased with time, becoming globally negligible after 2 years. Slight and moderate soil disturbance intensity site preparation techniques reduce erosion rates to 30% of potential erosion, halving the critical period when above tolerance rates may occur. Content Type Journal Article Category Original Paper Pages 1-14 DOI 10.1007/s10342-011-0581-6 Authors Tomás de Figueiredo, Centro de Investigação de Montanha (CIMO), Instituto Politécnico de Bragança/Escola Superior Agrária, Campus de Sta Apolónia, Apartado 1172, 5301-855 Bragança, Portugal Felícia Fonseca, Centro de Investigação de Montanha (CIMO), Instituto Politécnico de Bragança/Escola Superior Agrária, Campus de Sta Apolónia, Apartado 1172, 5301-855 Bragança, Portugal Afonso Martins, Universidade de Trás-os-Montes e Alto Douro, Apartado 1013, 5001-911 Vila Real, Portugal Journal European Journal of Forest Research Online ISSN 1612-4677 Print ISSN 1612-4669

Description: Recent studies indicate that soil soluble organic nitrogen (SON) plays an important regulatory role in the soil–plant N cycle. The aims of this study were to identify the vertical distribution of SON and its correlation with N mineralization, nitrification, and amidohydrolase activities, in a soil repeatedly amended with cow manure or chemical fertilizer. For this purpose, soil samples were collected from 0–20, 20–40, 40–60, 60–80, and 80–100 cm depths of a calcareous soil, which has been annually amended for 5 y with cow manure (CM) at two rates of 50 (CM 50 ) and 100 (CM 100 ) Mg CM ha –1 y –1 . Treatments with chemical fertilizer (CF) and a control (CT) were also included. Soluble organic N, N mineralization, nitrification rates, as well as L-glutaminase and L-asparaginase activities were determined. Both CM 50 and CM 100 enhanced SON content throughout the soil profile. Nitrogen-mineralization rate (N m ) was increased at the 0–20 cm depth of the CM 100 treatment and remained unaffected at the deeper depths. Nitrification rate (N n ) was significantly higher at the 0–60 cm depth of CM 100 compared to CF and CT. L-glutaminase and L-asparaginase activities were significantly increased at the 0–40 cm depth in both CM 50 and CM 100 compared to CF and CT. The amidohydrolase activities could not be detected below 40 cm, regardless of the fertilizer treatments. Our results suggest that SON makes a minor contribution to N mineralization in deep soil layers. It was also concluded that changes in the SON throughout the soil profile were not associated with changes in the N-transformation rates (N m and N n ) and amidohydrolase activities. While we conclude that SON is a major N pool in the whole profile of the manure applied soil further investigation is required to characterize SON and to investigate the bioavailability of SON for microbial activity in different soil depths.

Description: Wind effects on trees Content Type Journal Article Category Editorial Pages 1-5 DOI 10.1007/s10342-011-0582-5 Authors Dirk Schindler, Meteorological Institute, Faculty of Forest and Environmental Sciences, Albert-Ludwigs-University, Freiburg, Germany Jürgen Bauhus, Institute of Silviculture, Faculty of Forest and Environmental Sciences, Albert-Ludwigs-University, Freiburg, Germany Helmut Mayer, Meteorological Institute, Faculty of Forest and Environmental Sciences, Albert-Ludwigs-University, Freiburg, Germany Journal European Journal of Forest Research Online ISSN 1612-4677 Print ISSN 1612-4669

Description: Due to energy crises and stricter environmental regulations, renewable energy sources like bio-methane produced by anaerobic digestion (biogas) become increasingly important. However, the application of slurries produced by biogas fermentation to agricultural land and subsequent ammonia emission may also create environmental risks to the atmosphere and to N-limited ecosystems. Evaluating ammonia loss from agricultural land by model simulation is an important tool of agricultural-systems analysis. The objective of this study was the systematical comparison of ammonia volatilization after application of two types of biogas slurries containing high amounts of energy crops in comparison with conventional animal slurries and to investigate the relative importance of factors affecting the emission process through an empirical model. A high number of ammonia-loss field measurements were carried out in the years 2007/08 in biogas cropping systems in N Germany. The study consisted of simultaneous measurement of NH 3 losses from animal and biogas slurries in multiple-plot field experiments with different N-fertilization levels. The derived empirical model for the calculation of NH 3 losses based on explanatory variables gave good predictions of ammonia emission for both biogas and pig slurries. The root mean square error ( RMSE ) and mean bias error ( MBE ) of the empirical model for validation data were 2.19 kg N ha –1 ( rRMSE 29%) and –1.19 kg N ha –1 , respectively. Biogas slurries produced highest NH 3 emissions compared to the two animal slurries. In view of the explanatory variables included in the model, total NH application rate, slurry type, temperature, precipitation, crop type, and leaf-area index were important for ammonia-volatilization losses.

Description:    This research encompasses soil CO 2 emission studies from forest and pasture couplets located in northwestern Spain, where two mature oak forest ecosystems partially cleared for pasture 5 or 50 years ago were selected to monitor soil C effluxes during 2 years. The CO 2 exchanges in the soil–atmosphere interphase of forest and pasture plots were seasonally determined using portable infrared gas analysers. At the same time, soil samples from both forest and pasture ecosystems were used to carry out long-term incubations under laboratory conditions. Solid-state 13 C-NMR with cross-polarization/magic angle spinning was applied to determine the deforestation effects on soil organic matter (SOM) composition. Pasture implantation caused a notable decline of the labile C pool and a decrease in the total soil C, with an increase in both the SOM humification and the relative concentration of phenolic and carboxyl C. After only 5 years, the deforestation caused a general decrease in the soil CO 2 emissions with reduced seasonal fluctuations, these effects being even more intense 50 years after clearing. The correlation observed in oak forests between the CO 2 measured in situ and the soil temperature, is masked in pasture ecosystems by the high summer soil dryness. After the partial disappearance of soil C stocks caused by deforestation, a new long-term C input/output equilibrium seems to be established, probably due to the joint adaptation of both SOM and microbial communities in the old pasture soil; however, the entire soil C retention capacity remains still degraded as compared with the original uncleared forest ecosystem. Content Type Journal Article Category Original Paper Pages 1-13 DOI 10.1007/s10342-011-0580-7 Authors Irene Fernandez, Departamento de Bioquímica del Suelo, Instituto de Investigaciones Agrobiológicas de Galicia, Consejo Superior de Investigaciones Científicas (CSIC), Apartado 122, 15780 Santiago de Compostela, Spain Beatriz Carrasco, Departamento de Bioquímica del Suelo, Instituto de Investigaciones Agrobiológicas de Galicia, Consejo Superior de Investigaciones Científicas (CSIC), Apartado 122, 15780 Santiago de Compostela, Spain Ana Cabaneiro, Departamento de Bioquímica del Suelo, Instituto de Investigaciones Agrobiológicas de Galicia, Consejo Superior de Investigaciones Científicas (CSIC), Apartado 122, 15780 Santiago de Compostela, Spain Journal European Journal of Forest Research Online ISSN 1612-4677 Print ISSN 1612-4669

Description:    In this article, the development and operationalisation of forestry-wood chain indicators within the frame of sustainability impact assessment are discussed. The analytical framework follows a distinction between indicator definition and selection in a first phase, and a second operational phase of indicator application in terms of interconnecting material flows, calculation of chain performance and utilisation within evaluation components. A clear boundary drawing effort in terms of the development of indicator definitions, related subclasses, and measurement units as well as the creation of conversion factors between indicator values and individual chain stages supports this. Economic, social and environmental indicators have to respond to data collection needs on individual process levels (that correspond to sub-divisions of the forestry-wood chain). For the usage of indicators within evaluation tools, a functional hierarchy has to be provided that supports clear preference elicitation as well as information on related externalities. In total, this paper aims at demonstrating an enhanced spectrum in the use of sustainability indicators, and the challenges that arise from a developing and applying multi-functional indicators in sustainability impact assessment. Content Type Journal Article Category Original Paper Pages 1-12 DOI 10.1007/s10342-011-0547-8 Authors Helga Pülzl, Department of Political Science and Sociology, University of Salzburg, Rudolfskai 42, 5020 Salzburg, Austria Irina Prokofieva, Forest Sciences Center of Catalonia (CTFC), Forest Economics Area, Ctra. De St. Llorenç de Morunys, km. 2, 25280 Solsona, Spain Staffan Berg, The Forestry Research Institute of Sweden, SkogForsk, Uppsala Science Park, 75183 Uppsala, Sweden Ewald Rametsteiner, EFICEEC c/o Department of Economics and Social Sciences, BOKU University of Natural Resources and Applied Life Sciences Vienna, Feistmantelstraße 4, 1180 Vienna, Austria Filip Aggestam, EFICEEC c/o Department of Economics and Social Sciences, BOKU University of Natural Resources and Applied Life Sciences Vienna, Feistmantelstraße 4, 1180 Vienna, Austria Bernhard Wolfslehner, EFICEEC c/o Department of Economics and Social Sciences, BOKU University of Natural Resources and Applied Life Sciences Vienna, Feistmantelstraße 4, 1180 Vienna, Austria Journal European Journal of Forest Research Online ISSN 1612-4677 Print ISSN 1612-4669

Description: Soil sulfur (S) partitioning among the various pools and changes in tropical pasture ecosystems remain poorly understood. Our study aimed to investigate the dynamics and distribution of soil S fractions in an 8-year-old signal grass ( Brachiaria decumbens Stapf.) pasture fertilized with nitrogen (N) and S. A factorial combination of two N rates (0 and 600 kg N ha –1 y –1 , as NH 4 NO 3 ) and two S rates (0 and 60 kg S ha –1 y –1 , as gypsum) were applied to signal grass pastures during 2 y. Cattle grazing was controlled during the experimental period. Organic S was the major S pool found in the tropical pasture soil, and represented 97% to 99% of total S content. Among the organic S fractions, residual S was the most abundant (42% to 67% of total S), followed by ester-bonded S (19% to 42%), and C-bonded S (11% to 19%). Plant-available inorganic SO 4 -S concentrations were very low, even for the treatments receiving S fertilizers. Low inorganic SO 4 -S stocks suggest that S losses may play a major role in S dynamics of sandy tropical soils. Nitrogen and S additions affected forage yield, S plant uptake, and organic S fractions in the soil. Among the various soil fractions, residual S showed the greatest changes in response to N and S fertilization. Soil organic S increased in plots fertilized with S following the residual S fraction increment (16.6% to 34.8%). Soils cultivated without N and S fertilization showed a decrease in all soil organic S fractions.

Description: A greenhouse pot experiment was carried out to investigate the effects of different P-fertilizer application forms (triple superphosphate [TSP], compost + TSP, TSP-enriched compost) on the growth of ryegrass and the soil microbial biomass. The fertilizers were applied at equivalent doses for all nutrients to a neutral Luvisol in comparison with an acidic Ferralsol. Fertilizer application led to significantly increased contents of microbial biomass C, N, and P. Furthermore, yields of shoot C and root C, and concentrations of P, Ca, Mg, K, Fe, and Mn in shoots and roots were significantly increased. These increases always followed the order TSP 〈 compost + TSP 〈 TSP-enriched compost. Sole TSP application led only to maximum concentrations of N and S. In the Ferralsol, TSP had only minimal positive effect on the P concentration of the grass shoots. The positive effect of TSP-enriched compost, i.e., incubating TSP together with compost for 24 h, did not differ between the neutral Luvisol and the acidic Ferralsol, i.e., the effect is independent of the soil type. Consequently, soluble inorganic P fertilizer should generally be mixed into an organic fertilizer before application to soil.

Description: The physical properties of a Luvisol derived from loess near Bonn, Germany, under different long-term fertilization treatments were examined. For the investigation of the impact of farmyard manure (FYM) on soil strength at the mesoscale (100 to 300 cm 3 soil cores), undisturbed samples were taken from two different depths (10 and 40 cm), either with no fertilization at all, with full mineral fertilization, with FYM only, and with both mineral and organic fertilization. We investigated hydraulic and mechanical parameters, namely precompression stress, pore-size distribution, saturated hydraulic and air conductivity, and calculated pore connectivity. Long-term organic fertilization resulted in significantly more and coarser pores which in addition were more conductant and mechanically stronger by trend. Mineral fertilization also increased pore volume by trend but not pore functionality. Mechanical strength generally increased with fertilization by trend, however, was reduced again when organic and mineral fertilization were combined. Nonetheless, FYM led to relatively higher soil strength as the FYM-treated plots with lower bulk density attained similar soil strength as the unfertilized but denser plots and thus supported the soil-improving impact of organic amendments. The subsoil physical properties were rather unaffected by fertilization, but were dominated by texture.

Description: Little is known about nutrient fluxes and nutrient-use efficiencies in urban and peri-urban agriculture (UPA) of rapidly expanding cities in developing countries. Therefore, horizontal flows of carbon (C), nitrogen (N), phosphorus (P), and potassium (K) as well as leaching losses of mineral N and P were measured over 2 years in three representative agricultural production systems of Kabul. These comprised 21 gardens and 18 fields dedicated to vegetable farming, cereal farming, and table-grape production (vineyards). Across sites (fields and gardens) biennial inputs averaged 375 kg N ha –1 , 155 kg P ha –1 , 145 kg K ha –1 , and 15 kg C ha –1 while with harvests 305 kg N ha –1 , 40 kg P ha –1 , 330 kg K ha –1 , and 7 kg C ha –1 were removed. In vegetable gardens, biennial net balances were 80 kg N ha –1 , 75 kg P ha –1 , –205 kg K ha –1 , and 4 kg C ha –1 , whereas in cereal farming biennial horizontal balances amounted to –155 kg N ha –1 , 20 kg P ha –1 , –355 kg K ha –1 , and 5 kg C ha –1 . In vineyards, corresponding values were 295 kg N ha –1 , 235 kg P ha –1 , 5 kg K ha –1 , and 3 kg C ha –1 . Annual leaching losses in two selected vegetable gardens varied from 70 to 205 kg N ha –1 and from 5 to 10 kg P ha –1 . Night soil and irrigation water were the major sources among the applied nutrient inputs in all studied farming systems, contributing on average 12% and 25% to total N, 22% and 12% to total P, 41% and 53% to total K, and 79% and 10% to total C, respectively. The results suggest that soils in extensive cereal fields are at risk of N and K depletion and in vegetable gardens of K depletion, while vineyards may be oversupplied with nutrients possibly contributing to groundwater contamination. This merits verification.

Description: Residues from biogas production contain essential plant nutrients such as nitrogen (N), phosphorus (P), and potassium (K) but also organic matter, and should be recycled in crop production. For efficient re-use as fertilizers, the availability of nutrients for crops and the effect of the residues on soil fertility need to be evaluated. Focusing on the element P, we compared effects of codigested slurry with dairy slurry, highly soluble mineral NPK fertilizer, and a control without any P supply (NK). Codigested slurry used in this experiment was based on anaerobic digestion of dairy slurry, maize silage, and wheat grain. The fertilizing effects were tested in an 8-week pot experiment on a sandy and a loamy soil using two crop species ( Zea mays L., Amaranthus cruentus L.). The plant P uptake was up to 64% greater in the slurry treatments than in the treatment without P. The effect of codigested slurry on P uptake was comparable to that of dairy slurry and mineral P. Plant N uptake from codigested slurry was lower than that from mineral N (NK, NPK), but tended to be higher than from dairy slurry. The water-soluble and double lactate–soluble P content of the soil was lower in the slurry treatments than in the mineral-P treatments and accompanied by higher contents of microbial-bound P. Differences between both organic fertilizers were detected for dehydrogenase activity which was up to 32% lower in soils fertilized with codigested slurry than it was in soils fertilized with dairy slurry. Our results indicate that codigestion of slurries in biogas plants does not substantially alter their fertilizer value as P and N sources for crops.

Description: The effect of different deficit-irrigation treatments on the dynamics of mineral nutrients in leaves of peach trees growing under Mediterranean conditions was studied. Treatments consisted of a control, continuous deficit irrigation, regulated deficit irrigation, and partial root drying. The dynamics of nutrients were unchanged by the water deficits, though the amount absorbed was slightly modified. The advantages of deficit-irrigation strategies with regard to water-use efficiency were accompanied by the absence of any harmful effect on leaf mineral nutrition.

Description: It has been suggested that short-term field experiments are not suitable for the quantitative assessment of cropping-systems impact on soil organic matter (SOM) levels in arable soils, as expectable temporal changes are very small compared to a large spatial variation of SOM background levels. However, applying an optimized sampling design based on repeated sampling in small plots, we were able to detect soil total carbon (STC) and nitrogen (STN) changes in the magnitude of ≈ 1% (STC) and ≈ 2% (STN) of background levels with only four replications, respectively. Gradually enlarging the sample size up to n = 24 did not considerably improve change detectability with STC, but with STN ( n = 15 allowing for the dection of ≈ 1% change of background levels). The common calculation of minimum detectable differences (MDD) based on a state analysis of SOM levels instead of repeated measurements considerably underestimated change detectability.

Description: Two experiments were conducted to study the effect of grafting on nitrogen-use efficiency (NUE) in mini-watermelon plants. In the first study, mini-watermelon plants ( Citrullus lanatus [Thumb.] Matsum. and Nakai cv. Minirossa) either ungrafted or grafted onto Macis, Vita ( Lagenaria siceraria [Mol.] Standl.), PS1313, and RP15 ( Cucurbita maxima Duchesne × Cucurbita moschata Duchesne) rootstocks grown in hydroponics were compared in terms of shoot dry biomass, leaf area, root-to-shoot ratio, SPAD index, shoot N uptake, and nitrate reductase (NR) activity 40 d after transplantation in response to nitrate concentration in the nutrient solution (0.5, 2.5, 5, 10, 15, or 20 mM of NO ). In the second experiment, the suitability of a selected rootstock with high NUE (Vita) to improve crop performance and NUE of grafted mini-watermelon plants was evaluated under field conditions. In the hydroponic experiment mini-watermelon grafted onto Vita rootstock needed the lowest nitrate concentration (1.31 mM of NO 3 ) in the nutrient solution to reach half maximum shoot dry weight. Total leaf area, SPAD index, and shoot N uptake increased in response to an increase of N concentration in the nutrient solution. At 2.5 mM NO , mini-watermelon grafted on either Vita or RP15 had the highest NR activity whereas no significant difference was observed at 10 mM NO . The open-field study indicated that increasing N-fertilization rates from 0 to 100 kg ha –1 improved total and marketable yields of mini-watermelon plants while decreasing NUE. When averaged over N levels, the marketable yield, NUE, N-uptake efficiency, and N-utilization efficiency were significantly higher by 39%, 38%, 21%, and 17%, respectively, in Minirossa grafted onto Vita compared to ungrafted Minirossa plants. Therefore, grafting mini-watermelon plants onto selected rootstocks can be used as a quick and effective method for improving productivity and NUE.

Description:    Soil water availability determines the vitality of trees and forest stands to a large degree. Over the last decades, an increasing number of drought spells has been observed in several parts of Europe. Our study aims to estimate long-term trends of soil drought at Scots pine ( Pinus sylvestris L.) stands along the prevailing climatic gradient in Mecklenburg-Western Pomerania, northeastern Germany. To this end, soil water balance simulations were carried out at 24 sites over the period from 1951 to 2009 with the physically based model LWF-BROOK90. As a threshold for soil water stress, we used 40% of relative extractable water (REW). The results indicated an increased number of drought days further east, together with declining totals of precipitation. However, specific site conditions had a large influence on the occurrence of soil drought, partly overriding the climatic differences across the study area. Soil drought has distinctly increased in the recent past, both in duration and in intensity, affecting the eastern sites more than the western sites. The increased soil dryness could be attributed to higher atmospheric evaporative demand due to higher temperatures, as well as slightly lower precipitation sums during the summer months. To mitigate the negative effects of future climate change, adaptation measures should preferably be conducted in the eastern parts of northeastern Germany. Content Type Journal Article Category Original Paper Pages 1-12 DOI 10.1007/s10342-011-0573-6 Authors Andreas Bauwe, Universität Rostock, Agrar- und Umweltwissenschaftliche Fakultät, Justus-von-Liebig-Weg 6, 18059 Rostock, Germany Christian Criegee, Universität Rostock, Agrar- und Umweltwissenschaftliche Fakultät, Justus-von-Liebig-Weg 6, 18059 Rostock, Germany Stephan Glatzel, Universität Rostock, Agrar- und Umweltwissenschaftliche Fakultät, Justus-von-Liebig-Weg 6, 18059 Rostock, Germany Bernd Lennartz, Universität Rostock, Agrar- und Umweltwissenschaftliche Fakultät, Justus-von-Liebig-Weg 6, 18059 Rostock, Germany Journal European Journal of Forest Research Online ISSN 1612-4677 Print ISSN 1612-4669

Description:    Despite evidences that Holm oak has a high plasticity and great adaptability, there is limited or contradictory knowledge of the morphological and physiological variability of this species. Holm oak has been widely used for reforestation projects in Mediterranean areas, but has frequently shown poor field performance. We hypothesized that Holm oak has inter-population differences in physiological responses to abiotic stressors that could affect reforestation success. The influence of nursery culture on the characteristics of Holm oaks from different provenances has not been explored in depth. Thus, we studied the effect of nursery autumn fertilization on morphological traits, frost tolerance, root growth potential, and nutritional status of two Spanish provenances of Holm oak, La Alcarria (a region with inland Mediterranean climate) and Sierra Morena Occidental (a region with a warm coastal Mediterranean climate). There were significant differences between the provenances in frost tolerance, biomass allocation, and leaf nutrient content, suggesting a role of genetic factors. The leaves of seedlings from La Alcarria had less visual damage at −12°C than seedlings from the warmer provenance (45% vs. 92%). Seedlings from La Alcarria, compared to those from Sierra Morena, had higher leaf P concentration (0.17% vs . 0.15%), greater stem diameter (3.1 mm vs . 2.7 mm), lower shoot-to-root dry mass ratio (0.46 vs . 0.53), and lower slenderness (4.03 vs . 5.31). For both provenances, N autumn fertilization improved growth, root growth potential, cold hardiness, and nutritional status of seedlings. We suggest that forest reforestation programs should consider to a greater extent Holm oak provenances and their tolerances to different abiotic stressors. Content Type Journal Article Category Original Paper Pages 1-11 DOI 10.1007/s10342-011-0578-1 Authors Enrique Andivia, Departamento de Ciencias Agroforestales, Universidad de Huelva, Escuela Técnica Superior de Ingeniería, Campus Universitario de La Rábida Palos de la Frontera, 21819 Huelva, Spain Manuel Fernández, Departamento de Ciencias Agroforestales, Universidad de Huelva, Escuela Técnica Superior de Ingeniería, Campus Universitario de La Rábida Palos de la Frontera, 21819 Huelva, Spain Javier Vázquez-Piqué, Departamento de Ciencias Agroforestales, Universidad de Huelva, Escuela Técnica Superior de Ingeniería, Campus Universitario de La Rábida Palos de la Frontera, 21819 Huelva, Spain Reyes Alejano, Departamento de Ciencias Agroforestales, Universidad de Huelva, Escuela Técnica Superior de Ingeniería, Campus Universitario de La Rábida Palos de la Frontera, 21819 Huelva, Spain Journal European Journal of Forest Research Online ISSN 1612-4677 Print ISSN 1612-4669

Description:    Patterns in radial growth have often been used to predict forest decline since they are regarded as indicators of the tree responses to long-term stressors. However, the sensitivity of tree growth to climate, as a proxy of the trees’ adaptive capacity to short-term climatic stress, has received less attention. Here, we used retrospective tree-ring analyses to determine whether growth patterns and sensitivity to climate are related to Abies alba (silver fir) decline in the Spanish Pyrenees. We used regional climatic data to calculate normalised temperatures and drought indexes. Basal-area increment (BAI) was measured for declining (defoliation 〉50%) and non-declining (defoliation 〈50%) silver firs in four stands with contrasting decline levels. A dynamic factor analysis (DFA) was applied to test the hypothesis that declining and non-declining trees have experienced different long-term growth trends. Growth sensitivity to climate was computed as the average change in BAI per unit of change in a given climate variable. Declining trees showed a negative growth trend during the last 20 years. Trees with lower relative BAI and negative BAI trends showed stronger growth sensitivity to climate and higher defoliation than trees with the opposite characteristics. Our findings underscore the idea that long-term climatic warming seems to be a major driving factor of growth decline in Pyrenean silver fir forests. Ongoing growth reduction and enhanced growth sensitivity to climate may promote vegetation shifts in these declining forests located near the xeric edge of the species distribution area. Content Type Journal Article Category Original Paper Pages 1-12 DOI 10.1007/s10342-011-0572-7 Authors Juan Carlos Linares, Área de Ecología, Universidad Pablo de Olavide, Ctra. Utrera km. 1, 41002 Sevilla, Spain J. Julio Camarero, ARAID, Instituto Pirenaico de Ecología (CSIC), Avda. Montañana 1005, 50192 Zaragoza, Spain Journal European Journal of Forest Research Online ISSN 1612-4677 Print ISSN 1612-4669

Description:    The development of ToSIA (tool for sustainability impact assessment of the Forest Wood Chain) involved to measure economic, social and environmental indicators of all transformation processes belonging to the Forest Wood Chain (FWC). In this context, a specific tool has been developed to measure indicators related to almost all transport processes of each European FWC. The aim of this article is to describe the approach and the method used to set up this tool and also to illustrate some of its applications through an example. The example shows how the tool can deal with major transport issues by determining, in a German case, the distances (respectively, 330 and 280 km) setting the economic advantage to use rail and inland waterways instead of road. Moreover, it evaluates the implications of such changes in term of Green House Gas reduction (respectively, 50 and 56%). Content Type Journal Article Category Original Paper Pages 1-8 DOI 10.1007/s10342-011-0530-4 Authors Jean-Baptiste Chesneau, FCBA—Pôle EEP, 10 avenue de Saint Mandé, 75012 Paris, France Elisabeth Le Net, FCBA—Pôle EEP, 10 avenue de Saint Mandé, 75012 Paris, France Staffan Berg, The Forest Research Institute of Sweden, Uppsala Science Park, SE-751 83 Uppsala, Sweden Journal European Journal of Forest Research Online ISSN 1612-4677 Print ISSN 1612-4669

Description:    The genus Quercus , which belongs to the family Fagaceae , is native to the northern hemisphere and includes deciduous and evergreen species. The trees of the different species are very important from both economic and ecological perspectives. Application of new technological approaches (which span the fields of plant developmental biology, genetic transformation, conservation of elite germplasm and discovery of genes associated with complex multigenic traits) to these long-rotation hardwoods may be of interest for accelerating tree improvement programs. This review provides a summary of the advances made in the application of biotechnological tools to specific oak species. Significant progress has been made in the area of clonal propagation via organogenesis and somatic embryogenesis (SE). Standardized procedures have been developed for micropropagating the most important European ( Q. robur , Q. petarea, Q. suber ) and American ( Q. alba , Q. bicolor , Q. rubra ) oaks by axillary shoot growth. Although regenerated plantlets are grown in experimental trials, large-scale propagation of oak species has not been carried out. The induction of SE in oaks from juvenile explants is generally not problematic, although the use of explants other than zygotic embryos is much less efficient. During the last decade, enormous advances have been made in inducing SE from selected adult trees, mainly specimens of pedunculate oak ( Q. robur ) and cork oak ( Q. suber ). Advances in the understanding of the maturation and germination steps are required for better use of embryogenic process in clonal forestry. Quercus species are late-maturing and late-flowering, exhibit irregular seed set, and produce seeds that are recalcitrant to storage by conventional procedures. Vitrification-based cryopreservation techniques were used successfully in somatic embryos of pedunculate oak and cork oak, and an applied genbank of cork oak selected genotypes is now under development. The feasibility of genetic transformation of pedunculate oak and cork oak somatic embryos by means of co-culture techniques with several strains of Agrobacterium tumefaciens has also been demonstrated. To date, most research on the genomics of Quercus species has concerned population genetics. Approaches using functional genomics to examine the molecular and cellular mechanisms that control organogenesis and or somatic embryogenesis are still scarce, and efforts on the isolation and characterization of genes related to other specific traits should be intensified in the near future, as this would help improve the practical application of clonal forestry in recalcitrant species such as oaks. Content Type Journal Article Pages 1-21 DOI 10.1007/s10342-011-0526-0 Authors Ana M. Vieitez, Instituto de Investigaciones Agrobiológicas de Galicia, CSIC, Avda. de Vigo s/n, Campus Sur, Apartado 122, 15780 Santiago de Compostela, Spain Elena Corredoira, Instituto de Investigaciones Agrobiológicas de Galicia, CSIC, Avda. de Vigo s/n, Campus Sur, Apartado 122, 15780 Santiago de Compostela, Spain M. Teresa Martínez, Instituto de Investigaciones Agrobiológicas de Galicia, CSIC, Avda. de Vigo s/n, Campus Sur, Apartado 122, 15780 Santiago de Compostela, Spain M. Carmen San-José, Instituto de Investigaciones Agrobiológicas de Galicia, CSIC, Avda. de Vigo s/n, Campus Sur, Apartado 122, 15780 Santiago de Compostela, Spain Conchi Sánchez, Instituto de Investigaciones Agrobiológicas de Galicia, CSIC, Avda. de Vigo s/n, Campus Sur, Apartado 122, 15780 Santiago de Compostela, Spain Silvia Valladares, Instituto de Investigaciones Agrobiológicas de Galicia, CSIC, Avda. de Vigo s/n, Campus Sur, Apartado 122, 15780 Santiago de Compostela, Spain Nieves Vidal, Instituto de Investigaciones Agrobiológicas de Galicia, CSIC, Avda. de Vigo s/n, Campus Sur, Apartado 122, 15780 Santiago de Compostela, Spain Antonio Ballester, Instituto de Investigaciones Agrobiológicas de Galicia, CSIC, Avda. de Vigo s/n, Campus Sur, Apartado 122, 15780 Santiago de Compostela, Spain Journal European Journal of Forest Research Online ISSN 1612-4677 Print ISSN 1612-4669

Description:    Knowledge on the natural dynamics of Norway spruce-European silver fir forests is scarce, but is of high importance for the sustainable management of these ecosystems. Using a unique data set from five forest reserves in the Swiss Alps that covers up to 35 years, we elucidated communalities and differences in stand structure and species composition across the reserves and over time and investigated the role of site conditions versus intrinsic forest dynamics. For the early and late successional phases, we found a clear relationship between stand structure (diameter distributions) and species composition. Two pathways of early succession were evident as a function of the disturbance regime. Thus, the spatial extent of disturbances in spruce-fir forests strongly determines the pathway in early succession. Contrary to earlier descriptions of clearly distinguishable optima phases, our data did not reveal a relationship between stand structure and species composition for the early, mid-, and late optimum phases. Although the reserves investigated here are characterized by highly different climatic and soil conditions, their temporal development was found to fit well into a single successional scheme, suggesting that in spruce-fir mountain forests, the life-history strategies of the tree species may have a stronger influence on successional trajectories than site conditions per se. Content Type Journal Article Pages 1-16 DOI 10.1007/s10342-011-0525-1 Authors Caroline Heiri, WSL Swiss Federal Institute for Forest, Snow and Landscape Research, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland Annett Wolf, Forest Ecology, Institute of Terrestrial Ecosystems, Department of Environmental Sciences, Swiss Federal Institute of Technology Zurich, 8092 Zurich, Switzerland Lukas Rohrer, Forest Ecology, Institute of Terrestrial Ecosystems, Department of Environmental Sciences, Swiss Federal Institute of Technology Zurich, 8092 Zurich, Switzerland Peter Brang, WSL Swiss Federal Institute for Forest, Snow and Landscape Research, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland Harald Bugmann, Forest Ecology, Institute of Terrestrial Ecosystems, Department of Environmental Sciences, Swiss Federal Institute of Technology Zurich, 8092 Zurich, Switzerland Journal European Journal of Forest Research Online ISSN 1612-4677 Print ISSN 1612-4669

Description:    Nectria flute canker is a fungal disease that results in cankers on Pinus radiata stems. The disease, caused by the pathogen Neonectria fuckeliana, is associated with commercial pruning operations that limit knot defect to a central core to promote growth of high-quality clearwood. Nectria flute canker is present in commercial plantation forests in parts of New Zealand and Chile. Symptoms of the disease, bark cracks, stem flattenings or depressions and flute cankers, were identified on 25 mature Pinus radiata trees. Trees were felled, and discs crosscut from within, and adjacent to, the disease symptoms. The discs were photographed, and three different methods were used to determine the extent of Nectria damage beyond the defect core into the valuable clearwood sheath. These methods included a visual assessment of photographs of internal damage and two quantitative methods, based on calculations of defect extent using image processing software. Overall, flute cankers were associated with the greatest degree of encased bark and severe decay pockets, and stem flattenings the least. None of the flattened stems had internal decay. The average damage to the clearwood sheath due to flute canker was 43%, whilst that for bark cracks and flattenings was 19 and 8%, respectively. Similar results were achieved using all three methods, and the preferred method would depend on the context of the study. Using a combination of all three methods provides a robust method for measuring the damage to internal wood quality by stem pathogens and other abiotic agents. Content Type Journal Article Pages 1-7 DOI 10.1007/s10342-011-0522-4 Authors A. J. M. Hopkins, Scion, Private Bag 3020, Rotorua, 3010 New Zealand C. L. Todoroki, Scion, Private Bag 3020, Rotorua, 3010 New Zealand D. Pont, Scion, Private Bag 3020, Rotorua, 3010 New Zealand Journal European Journal of Forest Research Online ISSN 1612-4677 Print ISSN 1612-4669

Description:    Enhancement of Juniperus thurifera recruitment and colonisation by oak and pine species has been related at the local level to changes in livestock pressure. We used forest inventory data from Castilla y León Autonomous Region (Central Spain), an area comprising 34% of the world range of J. thurifera , to assess whether this process is occurring at a larger scale. We compared tree composition and density in a set of 659 permanent plots over a 10-year period. Logistic models and redundancy analysis were used to assess the effect on this process of parameters such as livestock pressure, propagule availability and climatic conditions. Between 1992 and 2002, juniper woodlands became denser (1.31% juniper stem year −1 ) and tree diversity increased due to rapid colonisation by oaks and pines (2.21% occupied plots year −1 ). In addition, the presence of juniper increased in other types of forests at a moderate rate (0.6% y −1 ). Thus, we observed both a disruption of the borders between current forest types and a generalised increase in α-diversity of tree species. The seed source was the main factor explaining colonisation rate, suggesting that the pace of colonisation is critically constrained by the spatial configuration of the landscape and the local propagule availability of the colonising species. If the current colonisation trends continue, monospecific juniper woodlands will become very scarce by the end of the twenty-first century. Content Type Journal Article Pages 1-8 DOI 10.1007/s10342-011-0531-3 Authors José M. Olano, Laboratorio de Botánica, EUI Agrarias de Soria, Universidad de Valladolid, Los Pajaritos s/n, 42004 Soria, Spain Miguel A. Zavala, Departamento de Ecología, Edificio de Ciencias, Universidad de Alcalá, 28871 Alcalá de Henares, Madrid, Spain Vicente Rozas, Misión Biológica de Galicia, Consejo Superior de Investigaciones Científicas, Apdo. 28, 36080 Pontevedra, Spain Journal European Journal of Forest Research Online ISSN 1612-4677 Print ISSN 1612-4669

Description: An evaluation of the factors determining the occurrence and the properties of soils with low permeability occurring in vast areas in S Portugal was carried out taking into account the terrain morphology and the geology of the region. This paper deals with the variation patterns of the physical and chemical characteristics of soils from several soil toposequences that occur under different gradient slopes and on different parent rocks. Spatial variation of soil properties mainly depends on the composition of their cation-exchange complex, as the role of other factors, such as the mineralogy of the clay fraction, were of minor importance. There is often a stronger increment of Na and/or Mg than of Ca with depth, causing a variable degree of sodicity in some of these soils, to which waterlogging tendency of their upper horizons is related. Though the occurrence of these features is determined by the nature of the parent rock, their degree of expression varies primarily according to the topographic position of soils. Therefore, a catenary distribution including nonsodic Cambisols or Luvisols in the hillcrests and Stagnic Solonetz or Sodic Luvisols or Sodic Stagnosols in the topographic lows is common. Such soil characteristics are of utmost importance for irrigation suitability and management of these soils, and for environmental impacts assessment, as the region is vulnerable to desertification.

Description: Oxisols cover ≈ 23% of the land surface in the tropics and are utilized extensively for agricultural purposes in the tropical countries. Under the variable input types of agricultural systems practiced locally, some of these soils still appear to have problems in terms of proper soil classification and subsequently hinder attempts to implement sustainable agro-management protocols. The definition for Oxisols in Soil Survey Staff (1999) indicates that additional input is still required to refine the definition in order to resolve some of the outstanding classification problems. Therefore, the objective of this study is to examine the properties of some Oxisols and closely related soils in order to evaluate the classification of these soils. Soils from Brazil, several countries in Africa, and Malaysia were used in this study. Field observations provided the first indication that some of the presently classified kandi-Alfisols and kandi-Ultisols were closer to Oxisols in terms of their properties. Water-retention differences and apparent CEC of the subsurface horizons also supported this idea. The types of extractable Fe oxides and external specific surface areas of the clay fractions showed that many kandic horizons have surface properties that are similar to the oxic horizons. Micromorphology indicated that the genetic transition from the argillic to the oxic involves a diminishing expression of the argillic. Properties, such as CEC, become dominant. The kandic horizon is therefore inferred as a transition to the oxic horizon. It is proposed that the Oxisols be keyed out based only on the presence of an oxic horizon and an iso–soil temperature regime. The presence of a kandic horizon will be reflected at lower levels in Oxisols. The Oxisols will now be exclusive to the intertropical belt with an iso–soil temperature regime. The geographic extend of the Oxisols would increase and that of kandi-Alfisols and Ultisols would decrease. A few kandi-Alfisols and Ultisols in the intertropical area will have low CEC which would fail the weatherable mineral contents. The kandic subgroups of some Alfisols and Ultisols will be transitional between the low (〈 16 cmol c [kg clay] –1 )- and high (〉 24 cmol c [kg clay] –1 )-activity clay soils. The proposed changes to classification will contribute to a better differentiation of the landscape units in the field. Testing of the proposed classification on some Malaysian soils showed that the new definition for Oxisols provides a better basis for the classification of the local soils and the development of meaningful soil-management groups for plantations.

Description: Variability in soil properties is a complication for fertilization, irrigation, and amendment application. However, only limited progress has been made in managing soil variability for uniform productivity and increased water-use efficiency. This study was designed to ameliorate the poor-productivity areas of the variable sandy soils in Florida citrus groves by using frequent small irrigations and applying organic and inorganic soil amendments. Two greenhouse experiments were set up with sorghum and radish as bioassay crops in a randomized complete block design (RCBD). The factors studied were two soil-productivity classes (very poor and very good), two water contents (50% and 100% of field capacity), two amendments (phosphatic clay and Fe humate), and two amendment rates (10 and 25 g kg –1 for sorghum and 50 and 100 g kg –1 for radish). Amendments applied at 50 and 100 g kg –1 increased the water-holding capacity (WHC) of poor soil by 2- to 6-fold, respectively. The lower rates (10 and 25 g kg –1 ) of amendments were not effective in enhancing sorghum growth. The higher rates (50 and 100 g kg –1 ) doubled the radish growth as compared to the control. The results indicate that rates greater than 50 g kg –1 of both amendments were effective in improving water retention and increasing productivity. Irrigation treatment of 100% of field capacity (FC) increased the sorghum and radish growth by about 2-fold as compared with the 50%–water content treatment. The results suggest that the root-zone water content should be maintained near FC by frequent small irrigations to enhance water availability in excessively drained sandy soils. In addition, application of soil amendments in the root zone can enhance the water retention of these soils. Furthermore, managing variable sandy soils with WHC-based irrigation can increase water uptake and crop production in the poor areas of the grove.

Description:    Scots pine ( Pinus sylvestris L.) forests of many inner Alpine valleys have recently displayed a quick loss of vitality. A decline disease has been suggested as the cause, with drought as the main predisposing factor and the additional contribution of biotic agents inciting tree dieback. This study is focused on Valle d’Aosta, a dry, inner-Alpine region in NW Italy. We inferred vitality changes between years 2000 and 2007 by computing reductions in enhanced vegetation index (EVI). Image differencing was carried out on pre-processed Moderate Resolution Imaging Spectroradiometer (MODIS) imagery taken in late springtime and validated against ancillary ground truth. We: (1) tested whether EVI reductions in Scots pine forests were significantly higher than those of a control species and of a wetter region for the same species, (2) analyzed decline incidence as a function of site and topographic variables, and (3) assessed the relative influence of site and stand structure on decline probability by means of path analysis. Mean EVI in the study area increased due to an early onset of the 2007 growing season. Nevertheless, the incidence of decline was 6.3% and significantly greater for Scots pine than the control species and site. Low-elevation, northerly exposed sites exhibited the highest incidence of decline. Path analysis suggested that the most important determinants of decline probability were slope, solar radiation, and stand sparseness. Content Type Journal Article Category Original Paper Pages 1-12 DOI 10.1007/s10342-011-0570-9 Authors Giorgio Vacchiano, Department of Agriculture, Silviculture and Land Management, University of Torino, Via L. da Vinci 44, 10095 Grugliasco, TO, Italy Matteo Garbarino, Department of Agriculture, Silviculture and Land Management, University of Torino, Via L. da Vinci 44, 10095 Grugliasco, TO, Italy Enrico Borgogno Mondino, Department of Agricultural, Forestry and Environmental Economics and Engineering, University of Torino, Via L. da Vinci 44, 10095 Grugliasco, TO, Italy Renzo Motta, Department of Agriculture, Silviculture and Land Management, University of Torino, Via L. da Vinci 44, 10095 Grugliasco, TO, Italy Journal European Journal of Forest Research Online ISSN 1612-4677 Print ISSN 1612-4669

Description: A greenhouse experiment was conducted to evaluate the effects of humic substances extracted from composted sewage sludge on growth, phenological development, and photosynthetic activity of pepper ( Capsicum annuum L. cv. Piquillo) plants. Humic substances derived from composted sludge (HSS) were compared with those derived from leonardite (HSL). Two doses of both humic substances were assayed (200 and 500 mg C [L substrate] –1 ) and compared with a control (C). HSS showed higher nitrogen content and a higher percentage of aliphatic carbon, as well as a lower content of aromatic and phenolic carbon than HSL. HSS significantly increased plant dry-matter production (up to 560%), plant height (86%–151%), and leaf area (436%–1397%) during the early stages of pepper development. Net photosynthesis and stomatal conductance increased in the treatments with HSS (up to 48% and 63%, respectively) at the vegetative stage. In addition, HSS accelerated the phenological development of pepper plants, reducing significantly the number of days to flowering and ripening, which occurred 12 and 14 d earlier than in control plants, respectively. In general, the treatments with HSS and HSL did not markedly affect chlorophyll and nutrient concentrations in the leaves. At maturity, only small differences in total fruit yield, number of fruits per plant, and fruit size were observed between amended and control plants. The results suggest that the mechanisms through which HSS affected plant growth and development were not associated with an improved nutrient uptake. Although the identity of the growth-promoting factors remains to be found, the results suggest that they may be linked to the chemical structure of the humic substances.

Description:    Whole-tree harvesting (WTH), where logging residues are removed in addition to stems, is widely practised in Fennoscandian boreal forests. WTH increases the export of nutrients from forest ecosystems. The extent of nutrient removals may depend on tree species, harvesting method, and the intensity of harvesting. We developed generalized nutrient equations for Scots pine ( Pinus sylvestris L.), Norway spruce ( Picea abies Karsten), and birch ( Betula pendula Roth and Betula pubescens Ehrh.) stands to be able to calculate the amounts of nitrogen, phosphorus, potassium, and calcium in stems and above-ground biomass (stem and crown) as a function of stand volume. The equations were based on Fennoscandian literature data from 34 pine, 26 spruce, and 5 birch stands, and they explained, depending on the tree species and nutrient, 61–99% and 56–87% of the variation in the nutrient amounts of stems and above-ground biomass, respectively. The calculations based on the equations showed that nutrient removals caused by stem-only harvesting (SOH) and WTH per harvested stem m 3 were smaller in pine than in spruce and birch stands. If the same volume of stem is harvested, nutrient removals are, in general, nearly equal at thinnings and final cuttings in SOH, but larger in thinnings than final cuttings in WTH. If the principal aim is to minimize the nutrient removals per harvested stem m 3 , the harvesting should be done at mature pine stands. The effect of biomass removal on overall site nutrient status depends on site-specific factors such as atmospheric deposition, weathering of minerals, and the size of the nutrient pools in the soil. Content Type Journal Article Category Original Paper Pages 1-20 DOI 10.1007/s10342-011-0567-4 Authors Marjo Palviainen, Department of Forest Sciences, University of Helsinki, P.O. Box 27, 00014 Helsinki, Finland Leena Finér, Finnish Forest Research Institute, Joensuu Research Unit, P.O. Box 68, 80101 Joensuu, Finland Journal European Journal of Forest Research Online ISSN 1612-4677 Print ISSN 1612-4669

Description:    A severe oak decline is taking place across the Mediterranean region since the 1980s. Among the climatic and biological factors involved in this complex syndrome, the longhorn C. welensii is currently considered a major element. Furthermore, larval damage to young or healthy trees is being increasingly important and thereby also the need to manage this emerging pest species. This paper deals with quantifying the adult populations in the field in order to evaluate the potential performance of mass trapping as control method against C. welensii . We used a mark-recapture protocol using feeding traps, which was complemented with some nocturnal observations and additional laboratory studies. Research was conducted in the Cornalvo Natural Park (southwestern Spain) during two consecutive years (2008–2009). Data were analysed with classic closed population (CP) methods and Maximum Likelihood Spatially Explicit Capture-Recapture (ML SECR) detection models. The results strongly supported the potential success of mass trapping as control method for C. welensii , including a high trapping efficiency (70–81%), relatively low adult population density for a pest species (316 and 265 adults/ha in 2008 and 2009), movement pattern of flying adults and highly aggregated distribution of adults in trees with traps. We also found experimental evidence that most adults come to the traps close to emergence as showed body appearance , longevity estimates and female reproductive age at trapping time. We discuss the practical achievement of mass trapping as control method integrating behavioural and ecological perspectives and, though a large-scale field validation is still lacking, we conclude that mass trapping may be a potential tool to manage C. welensii populations in dehesa open woodlands. Content Type Journal Article Category Original Paper Pages 1-14 DOI 10.1007/s10342-011-0579-0 Authors Luis M. Torres-Vila, Servicio de Sanidad Vegetal, Consejería de Agricultura DRMAyE, Junta de Extremadura, Avda. de Portugal s/n, 06800 Mérida, Badajoz, Spain Álvaro Sanchez-González, Servicio de Sanidad Vegetal, Consejería de Agricultura DRMAyE, Junta de Extremadura, Avda. de Portugal s/n, 06800 Mérida, Badajoz, Spain Francisco Ponce-Escudero, Servicio de Sanidad Vegetal, Consejería de Agricultura DRMAyE, Junta de Extremadura, Avda. de Portugal s/n, 06800 Mérida, Badajoz, Spain Daniel Martín-Vertedor, Servicio de Sanidad Vegetal, Consejería de Agricultura DRMAyE, Junta de Extremadura, Avda. de Portugal s/n, 06800 Mérida, Badajoz, Spain Juan J. Ferrero-García, Servicio de Sanidad Vegetal, Consejería de Agricultura DRMAyE, Junta de Extremadura, Avda. de Portugal s/n, 06800 Mérida, Badajoz, Spain Journal European Journal of Forest Research Online ISSN 1612-4677 Print ISSN 1612-4669

Description: An accurate assessment of soil respiration is critical for understanding and predicting ecosystem responses to anthropogenic perturbation such as climate change, pollution, and agriculture. Infra-red gas analyzer (IRGA)–based field measurement is the most widely used technique for assessing soil-respiration flux rates. In this study, respiration rates obtained with two common IRGA systems (LI-COR 8100 and PP Systems EGM-4) were compared across three ecosystem types. Our results showed that both methods were highly comparable in their flux estimates, but the associated methodology used (notably the use or absence of a soil collar) resulted in greater uncertainty in flux rates and a greater degree of intrasite variation. Specifically, the use of collars significantly decreased the flux estimate for both IRGAs compared to the no-collar estimate. The disturbance caused by collar insertion was assumed to be a major factor in causing the differing flux estimates, with root and mycorrhizal severance likely being the main contributor. We conclude that the two IRGAs used in this study can be reliably compared for overall flux estimates but emphasis is needed to validate a common measurement methodology.

Description: Provision of appropriate fertilizer recommendations to smallholder farmers is becoming increasingly important, for reasons of food security, economic viability, and the need to maintain soil fertility. Oil palm is one of the most important crops in the humid tropics, but smallholder growers (〈 10 ha) typically have low yields, largely due to inadequate fertilizer inputs and/or incomplete harvesting. It is difficult to produce appropriate fertilizer recommendations for the smallholder growers, due to their large numbers and small farm sizes. In this work, we developed a way of transferring to smallholder growers the fertilizer recommendations that have been developed for nearby plantation fields using large fertilizer trials. The study site was in West New Britain Province, Papua New Guinea, and transfer of information was done using a geographic information system and maps of plantation fields, smallholder blocks, and soil types. The soil-map-unit descriptions were interpreted, and a unified classification system was derived. Then, fertilizer recommendations that had been made on a field-specific basis for the large plantations were allocated to soil types and thereby to individual smallholder blocks. In this way, block-specific fertilizer recommendations were made for more than 4000 individual smallholders. The procedures used were developed into a conceptual framework which is transferable to other regions. Recommendations can be updated as new information becomes available on smallholder block locations or plantation fertilizer recommendations.

Description: The efficacy of arbuscular mycorrhizae (AM) on nutrients, organic solutes, and antioxidant enzymes of wheat under salt stress was investigated and related to root colonization and plant productivity. The mycorrhizal inoculation increased N, P, K, Ca, and Mg uptake, soluble sugars, free amino acids, and proline accumulation, as well as peroxidase and catalase activities under saline conditions as compared to nonmycorrhizal plants. On the other hand, Na concentration was lower in mycorrhizal than in nonmycorrhizal plants grown under saline conditions. Arbuscular mycorrhizae protected wheat against the detrimental effects of salinity and stimulated its productivity. Hence, mycorrhizal colonization can play a vital role in the mitigation of the adverse effects of salinity by improving the wheat osmotic adjustment response, enhancing its defense system, and alleviating oxidative damage to cells. Arbuscular mycorrhizae are able to alter plant physiology in a way that empowers the plant to grow more efficiently on salt-affected lands.

Description:    Density estimators for k -tree distance sampling are sensitive to the amount of extra Poisson variance in distances to the k th tree. To lessen this sensitivity, we propose an adaptive composite estimator (COM). In simulated sampling from 16 test populations, a three-component composite density estimator (COM)–with weights determined by a multinomial logistic function of four readily available ancillary variables–was identified as superior in terms of average relative absolute bias. Results from a different set of nine validation populations–with widely different stem densities and spatial patterns of tree locations—confirmed that relative root mean squared errors (RRMSE) of COM were, on average, considerably lower than those obtained with the three-component k -tree density estimators. The RRMSE performance of COM improved with increasing values of k . With k  = 6 and sample sizes of 10, 20, and 30, the average relative bias of COM was between −5 and 5% in seven validation populations but in an open low-density savanna-like population bias reached −12% (1979 data) and 7% (1996 data). For k  = 6 and n  = 10, the RRMSE of COM was, in six of the nine validation populations, within 3.3 percentage points of the RRMSE for sampling with fixed-area plots. Jackknife estimates of the precision of COM estimates of density were negatively biased, leading to under-coverage (7%) of computed 95% confidence intervals. Content Type Journal Article Pages 1-14 DOI 10.1007/s10342-011-0502-8 Authors Steen Magnussen, Natural Resources Canada, Canadian Forest Service, 506 West Burnside Rd., Victoria, BC V8Z 1M5, Canada Lutz Fehrman, Department of Forest Inventory and Remote Sensing, Faculty of Forest Sciences and Forest Ecology, Georg-August-Universität Göttingen, Büsgenweg 5, 37077 Göttingen, Germany William J. Platt, Department of Biological Sciences 202 LSB, Louisiana State University, Baton Rouge, LA 70803, USA Journal European Journal of Forest Research Online ISSN 1612-4677 Print ISSN 1612-4669

Description:    Austrocedrus chilensis forests suffer from a disease caused by Phytophthora austrocedrae , which is found often in wet soils. We applied three widely used modelling techniques, with different data requirements, to model disease potential distribution under current environmental conditions: Mahalanobis distance, Maxent and Logistic regression. Each model was built using field data of health condition and landscape layers of environmental conditions (distance to streams, slope, aspect, elevation, mean annual precipitation and soil pH NaF). We compared model predictions by area under the receiver operating characteristic curve and Kappa statistics. A reasonable ability to predict observed disease distribution was found for each of the three modelling techniques. However, Maxent and Logistic regression presented the best predictive performance, with significant differences with respect to the Mahalanobis distance model. Our results suggested that if good absence data are available, Logistic regression should be used in order to better discriminate sites with high risk of disease. On the other hand, if absence data are not available or doubtful, Maxent could be a very good option. The three models predicted that around 50% (49–56%) of the currently asymptomatic forests are located on sites at risk of disease according to abiotic factors. Most of these asymptomatic forests surround the current diseased patches, at distances lower than 100 m from diseased patches. Management considerations and the scope of future studies were discussed in this article. Content Type Journal Article Pages 1-15 DOI 10.1007/s10342-011-0503-7 Authors L. La Manna, Laboratorio de Suelos, Centro de Investigación y Extensión Forestal Andino Patagónico and Universidad Nacional de la Patagonia San Juan Bosco, Ruta 259 km 4, C.C. 14, 9200 Esquel, Chubut Argentina S. D. Matteucci, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina T. Kitzberger, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina Journal European Journal of Forest Research Online ISSN 1612-4677 Print ISSN 1612-4669

Description:    Water availability and salt excess are limiting factors in Mexican mixed pine-oak forest. In order to characterise the acclimatation of native species to these stresses, leaf water (Ψ w ) and osmotic potentials (Ψ s ) of Juniperus flaccida, Pinus pseudostrobus and Quercus canbyi were measured under natural drought and non-drought conditions under two different aspects in the Sierra Madre Oriental. Factorial ANOVA revealed significant differences in Ψ w and Ψ s between two aspects, species and sampling dates. In general, all species showed high predawn and low midday values that declined progressively with increasing drought and soil–water loss. Seasonal and diurnal fluctuation of Ψ w and Ψ s were higher for J. flaccida and Q. canbyi than for P. pseudostrobus . Leaf Ψ w and Ψ s were mainly correlated with soil water content, while Ψ s of P. pseudostrobus were hardly correlated with environmental variables. Thus, species have different strategies to withstand drought . P. pseudostrobus was identified as a species with isohydric water status regulation, while J. flaccida and Q. canbyi presented water potential patterns typical for anisohydric species. The type of water status regulation may be a critical factor for plant survival and mortality in the context of climate change. Nevertheless, for precise conclusions about the advantages and disadvantages of each type, further long-term investigations are required. Content Type Journal Article Pages 1-13 DOI 10.1007/s10342-011-0507-3 Authors Wibke Himmelsbach, Departamento de Silvicultura, Facultad de Ciencias Forestales, Universidad Autónoma de Nuevo León (UANL), Apartado Postal 41, Carretera Nacional No 85, Km 145, 67700 Linares, NL Mexico Eduardo J. Treviño-Garza, Departamento de Silvicultura, Facultad de Ciencias Forestales, Universidad Autónoma de Nuevo León (UANL), Apartado Postal 41, Carretera Nacional No 85, Km 145, 67700 Linares, NL Mexico Humberto González-Rodríguez, Departamento de Ciencias Básicas, Facultad de Ciencias Forestales, Universidad Autónoma de Nuevo León (UANL), Apartado Postal 41, Carretera Nacional No 85, Km 145, 67700 Linares, NL Mexico Marco A. González-Tagle, Departamento de Silvicultura, Facultad de Ciencias Forestales, Universidad Autónoma de Nuevo León (UANL), Apartado Postal 41, Carretera Nacional No 85, Km 145, 67700 Linares, NL Mexico Marco V. Gómez Meza, Facultad de Economía, Universidad Autónoma de Nuevo León, Monterrey, NL Mexico Oscar A. Aguirre Calderón, Departamento de Silvicultura, Facultad de Ciencias Forestales, Universidad Autónoma de Nuevo León (UANL), Apartado Postal 41, Carretera Nacional No 85, Km 145, 67700 Linares, NL Mexico A. Eduardo Estrada Castillón, Departamento de Ciencias Básicas, Facultad de Ciencias Forestales, Universidad Autónoma de Nuevo León (UANL), Apartado Postal 41, Carretera Nacional No 85, Km 145, 67700 Linares, NL Mexico Ralph Mitlöhner, Burckhardt-Institute, Tropical Silviculture and Forest Ecology, Faculty of Forest Sciences and Forest Ecology, Georg-August University Göttingen, Büsgenweg 1, 37077 Göttingen, Germany Journal European Journal of Forest Research Online ISSN 1612-4677 Print ISSN 1612-4669

Description:    Using wood as a building material affects the carbon balance through several mechanisms. This paper describes a modelling approach that integrates a wood product substitution model, a global partial equilibrium model, a regional forest model and a stand-level model. Three different scenarios were compared with a business-as-usual scenario over a 23-year period (2008–2030). Two scenarios assumed an additional one million apartment flats per year will be built of wood instead of non-wood materials by 2030. These scenarios had little effect on markets and forest management and reduced annual carbon emissions by 0.2–0.5% of the total 1990 European GHG emissions. However, the scenarios are associated with high specific CO 2 emission reductions per unit of wood used. The third scenario, an extreme assumption that all European countries will consume 1-m 3 sawn wood per capita by 2030, had large effects on carbon emission, volumes and trade flows. The price changes of this scenario, however, also affected forest management in ways that greatly deviated from the partial equilibrium model projections. Our results suggest that increased wood construction will have a minor impact on forest management and forest carbon stocks. To analyse larger perturbations on the demand side, a market equilibrium model seems crucial. However, for that analytical system to work properly, the market and forest regional models must be better synchronized than here, in particular regarding assumptions on timber supply behaviour. Also, bioenergy as a commodity in market and forest models needs to be considered to study new market developments; those modules are currently missing. Content Type Journal Article Pages 1-14 DOI 10.1007/s10342-010-0463-3 Authors Ljusk Ola Eriksson, Department of Forest Resource Management, Swedish University of Agricultural Sciences, 90183 Umeå, Sweden Leif Gustavsson, Department of Engineering and Sustainable Development, Mid Sweden University, 831 35 Östersund, Sweden Riitta Hänninen, Finnish Forest Research Institute, P.O. Box 18, 01301 Vantaa, Finland Maarit Kallio, Finnish Forest Research Institute, P.O. Box 18, 01301 Vantaa, Finland Henna Lyhykäinen, Department of Forest Sciences, University of Helsinki, P.O. Box 27, 00014 Helsinki, Finland Kim Pingoud, VTT Technical Research Centre of Finland, Tekniikantie 2, P.O. Box 1000, 02044 VTT Espoo, Finland Johanna Pohjola, Department of Forest Sciences, University of Helsinki, P.O. Box 27, 00014 Helsinki, Finland Roger Sathre, Department of Engineering and Sustainable Development, Mid Sweden University, 831 35 Östersund, Sweden Birger Solberg, Department of Ecology and Natural Resource Management, Norwegian University of Life Sciences, P.O. Box 5044, 1432 Ås, Norway Jarle Svanaes, Norsk Treteknisk Institutt, P.O. Box 113, Blindern, 0314 Oslo, Norway Lauri Valsta, Department of Forest Sciences, University of Helsinki, P.O. Box 27, 00014 Helsinki, Finland Journal European Journal of Forest Research Online ISSN 1612-4677 Print ISSN 1612-4669

Description: Different procedures to investigate dissolved trace element concentration at the transition from unsaturated to saturated zone in soils were compared by concurrent sampling of soil solution and solid soil material in this zone. The in situ sampled soil solution from the percolated water was used to measure in situ concentrations, while solid soil material was used to measure concentrations at two liquid–solid ratios using batch experiments on 250 sample pairs. The liquid–solid ratios were 2 L kg –1 and 5 L kg –1 . At 5 L kg –1 , the ionic strength was adjusted with Ca(NO 3 ) 2 to a sample-specific value similar to in situ , while at 2 L kg –1 , the ionic strength was not adjusted. The extracted concentrations of most trace elements exhibited a statistically significant but weak correlation ( p value 〈 0.01) to the corresponding in situ concentrations. In the liquid–solid ratio of 2 L kg –1 extracts, Pb and Cr showed very poor comparability with the in situ equivalent. A likely cause was the enhanced dissolved-organic-C release in the extract due to the lower ionic strength compared to in situ conditions in combination with effects from drying and moistening soil samples. For the other elements, correlation increased in the order As 〈 Cu, Zn, Sb, Mo, V 〈 Cd, Ni, Co where adjustment of the ionic strength led to slightly better results. In addition to the element-specific shortcomings, it appeared that low concentration levels of in situ concentrations were generally underestimated by batch extraction methods. The liquid–solid ratio of 2 L kg –1 extracts could only be used as a method to predict exceedance of thresholds if a safety margin of approximately one order of magnitude higher than the thresholds was adopted. The ability of the batch-extraction methods to estimate in situ concentrations was equally limited.

Description: Tonoplast Na + /H + antiporters increase the salt resistance of various plant species, but very little is known about the role of these antiporters in the salt resistance of trees. Understanding the physiological responses of plants to salinity stress is of paramount importance in examining the salt resistance of transgenic plants. In this study, the wild-type poplar (WT; Populus × euramericana var. Neva) and its transgenic varieties (TR) that overexpress the AtNHX1 gene were exposed to various seawater concentrations (0%, 10%, 20%, and 30%) for 30 d to determine the effects of seawater on seedling growth, ion content, and photosynthetic productivity. Results show that TR plants grew much better than WT under saline conditions. Differences between WT and TR in most parameters were significant after 30 d exposure to 20% and 30% seawater concentrations. The dry weight of TR was higher than that of WT for each seawater treatment. Transgenic variety was able to maintain higher photosynthetic ability than WT upon exposure to salinity and maintained higher K + concentrations and K + : Na + ratio but had less Cl – compared with WT. This suggests that AtNHX1 has a critical role in the regulation of K + homeostasis, which in turn affects plant K + nutrition and salt resistance.

Description: Recent studies have documented adverse affects of urea on the establishment and growth of aerobic rice when applied at seeding. The following experiments were conducted to examine the relative importance of ammonia and nitrite (NO ) toxicities as mechanisms contributing to poor germination and early growth of aerobic rice. Soil was collected from an experiment in the Philippines where aerobic rice was grown continuously for 7 years. Subsamples of the soil were: (1) pretreated with sulfuric acid (0.5 M H 2 SO 4 added at 75 mL kg –1 ), (2) oven-heated at 120°C for 12 h, or (3) left untreated. In a greenhouse study N was applied to the untreated, acidified, and oven-heated soils as either urea or ammonium sulfate (0.0 or 0.3 g N kg –1 ). Plant height, root length, total biomass, and number of seminal roots were evaluated after 10 d. Microdiffusion incubations were used to assess the effects of soil pretreatment, N source, and N rate (0, 0.5, 1.0, 1.5 g N kg –1 ) on ammonia (NH 3 ) volatilization and germination. Nitrite incubations were conducted to establish a critical level for NO toxicity and measure the extractable NO and germination trends as affected by soil pretreatment, N source, and N rate. On untreated soil, urea reduced early growth and germination while ammonium sulfate caused no adverse effects. Progressively higher rates of urea increased NH 3 volatilization and inhibited germination, while oven-heating and acidification minimized the adverse effects. All treatment combinations (soil pretreatment, N source, N rate) had extractable NO levels below the critical level of 0.2 g N kg –1 , suggesting that ammonia and not NO toxicity was the principal cause of inhibition. Since the risk of NH 3 toxicity is highest just following urea hydrolysis, strategies to optimize the timing and placement of urea should be considered.

Description: Soil structure affects all soil functions especially those related to physical and biological processes. On the other hand, soil structure itself is directly affected by these agents. Hence, soil structure—from single pores to the pedon scale—is expected to reflect the capacity of soil to deliver ecosystem functions. We analyzed soil structure including its seasonal dynamics for two plots within the long-term fertilization experiment in Bad Lauchstädt (Germany). The different plots received very different amounts of mineral and organic fertilizers over a period of 106 y. The quantification of structural properties includes pore-size distribution and pore connectivity obtained by X-ray microtomography. We present a methodological approach for image analysis that allows to combine samples of different size and resolution to cover pores within one order of magnitude in diameter. The results for the different plots obtained in spring and summer are compared. We found that the enormous difference in energy input only affects the structure of the topsoil (Ap horizon) towards a higher porosity and pore-network connectivity and in terms of an increased resilience after tillage. However, the structural properties of the subsoil below the plowed horizon (Ah horizon) are not affected. We hypothesize that the structure of the subsoil reflects soil formation over much longer time scales, it allows for an increased turnover of soil organic matter, and it is rather stable at the time scale of the fertilization experiment.

Description: The organic matter supply can promote the dispersal and activity of applied plant growth–promoting rhizobacteria (PGPR), but the complementary effect of organic fertilization and PGPR application on the turnover of P is scarcely known. The effects of the application of two PGPR strains ( Pseudomonas fluorescens strain DR54 and Enterobacter radicincitans sp. nov. strain DSM 16656) alone and in combination with organic fertilization (cattle manure and biowaste compost) on growth and P uptake of maize ( Zea mays L.) and oilseed rape ( Brassica napus L.) were investigated under semi–field conditions. Furthermore, P pools and phosphatase activities in soil and the arbuscular mycorrhizal–fungi colonization of maize roots were examined. The organic-fertilizer amendments increased the growth and P uptake of both plant species and the soil P pools. The application of the E. radicincitans strain increased P uptake of oilseed rape when no organic fertilizer was added. Furthermore, the application of both bacterial strains increased the activities of phosphatases under both plant species. Here, the effect of the PGPR application even exceeded the effect of organic fertilization. The magnitude of this effect varied between the different fertilizing treatments and between the two bacterial strains. Phosphatase activities were increased to the greatest extent after application of P. fluorescens in the unfertilized soil. Under rape increases of 52% for acid phosphatase activities (ACP), 103% for alkaline phosphatase activities (ALP), and 133% for phosphodiesterase (PDE) were observed therewith. In the unfertilized soil, the application of P. fluorescens also resulted in a strong increase of the arbuscular mycorrhizal colonization of maize. We conclude that application of PGPR can promote the P mobilization and supply of crops in P-deficient soils, however, in combination with organic fertilization these effects might be masked by a general improved P supply of the crops. Interactive effects of applied bacterial strains and organic fertilization depend on the sort of organic fertilizer and crop species used.

Description: To ensure high yield and quality in organic vegetable production, crops often require additional fertilizer applied during the season. Due to the risk of contamination of edible plant products from slurry, plant-based fertilizers may be used as an alternative. The purpose of our work was to develop mobile green manures with specific high nutrient concentrations ( e.g., nitrogen [N], sulfur [S], and phosphorus [P]) that are released quickly after soil incorporation and that are easy to handle during storage and application. To distinguish from traditional green manures that are grown to improve soil fertility, the term “mobile green manures” is used for green-manure crops that are harvested in one field and then moved as a whole and used as fertilizer in other fields. To further investigate mobile-green-manure crops for use as efficient fertilizers, pot and field experiments were conducted with cauliflower ( Brassica oleracea botrytis ) and kale ( Brassica oleracea sabellica ) supplied with organic matter consisting of a wide range of plant species with varying nutrient concentrations. Further, field experiments were conducted with leek ( Allium porrum ) and celery ( Apium graveolens dulce ) supplied with increasing amounts of organic matter consisting of fresh, ensiled, or dried green manures. Results show that garden sorrel ( Rumex acetosa ), dyer's woad ( Isatis tinctoria ), and fodder radish ( Raphanus sativus ) harvested with a high leaf-to-stem ratio resulted in high P concentration, and cruciferous crops in high S concentration. Dyer's woad, salad burnet ( Sanguisorba minor ), and stinging nettle ( Urtica dioica ) showed high boron (B) concentration, whereas species such as dandelion ( Taraxacum officinale ), chicory ( Cichorium intybus ), and garden sorrel showed high potassium (K) concentration. Green manures with high P and S concentrations increased the nutrient uptake and yield of pot-grown cauliflower and kale. Field experiments showed that the production of cauliflower and kale decreased when the carbon-to-nitrogen (C : N) ratio of applied green manure increased. In kale, for example, application of 160 kg N ha –1 in early harvested lucerne ( Medicago sativa ) with a C : N ratio of 10 resulted in the highest kale production whereas application of an equal amount of N in late harvested lucerne with a C : N ratio of 20 produced 34% less. Differences in vegetable production were not due to the amount of N applied, but to the N availability. Field experiments with fresh, ensiled, or dry green manure applied to leek and celery showed that the C : N ratio has to be low to get a fast response. Further, these field experiments demonstrate the importance of green manures, which can be stored and are easy to handle during transport, crop application, and soil incorporation. It is concluded that it is possible to produce green manures with high concentrations of S, P, K, and B, and low C : N ratios and that these properties have a great impact on the value of the green manure for vegetable production.

Description: Splash cups have long been successfully used for both the quantification of kinetic energy of rainfall and the detachability of soil particles by rainfall impact, the so-called “splash erosion”. Measurements of kinetic energy, however, have been difficult to operate in the field especially in remote areas, on steep slopes, and in forests since boundary conditions need to be controlled precisely. This paper introduces a new splash cup based on Ellison's archetype that reliably and accurately measures kinetic energy as a function of sand loss under a large variety of conditions. The Tübingen splash cup (T splash cup) is relatively easy to operate under harsh field conditions, and it can be used in experimental designs with a large number of plots and replications at reasonably low costs. The cup is constructed from plastic laboratory flasks and plastic pipes from water-supply equipments. The unit sand is held by a removable carrier system that can easily be replaced in the field. The splash cups have been calibrated in combination with a laser distrometer using a linear regression function with r 2 = 0.98. They measure kinetic energy over a wide range of rainfall intensities from 0.6 to 40 L m –2 h –1 . Kinetic energy per area varies between 10 and 250 J m –2 . Two years of field test measurements in a subtropical forest ecosystem in China proved the reliability, durability, and usability of our new splash cups and allowed detecting differences in kinetic energy between different tree species and biodiversity levels.

Description:    Individual and family heritabilities and juvenile–mature genetic correlations were estimated for growth and biomass traits recorded in treatment with optimal and limiting water and/or nutrient availability to study how the different growth environments affected genetic parameter estimates. Thirty open-pollinated families, randomly selected among the 58 families used in field progeny tests in Galicia, were cultivated for 30 weeks in a climatic chamber under controlled conditions. Two water regimes (high and low water supply) combined with two nutrient regimes (high and low nutrient supply) were applied by subirrigation. Several growth, branching and dry mass traits were assessed 30 weeks after sowing and compared with field performance (height, diameter and volume) of 4-year-old progeny tests established at three different sites in Galicia (NW Spain). Both the irrigation and the fertilization treatments had a strong effect in all the assessed traits except irrigation for the number of branches. Heritabilities for growth and biomass traits were moderate to high (0.13–0.77) in individual treatments. However, when analyzing all treatments together, the impact of the family × treatment interactions led to a reduction (0.20–0.35) in the heritability estimates. The results indicated that the genotype × water and genotype × nutrient interactions may be important and could not be ignored in the Galician radiata pine breeding program. Climatic chamber–field correlations were different between different traits measured at climatic chamber experiments and the three field tests. The correlations were larger with the well-watered treatments, suggesting that further development of early testing methods for radiata pine in Galicia should include treatments with no limiting water availability. Content Type Journal Article Pages 1-9 DOI 10.1007/s10342-011-0501-9 Authors V. Codesido, CINAM-Lourizán, Ap. 127, 36080 Pontevedra, Spain R. Zas, CINAM-Lourizán, Ap. 127, 36080 Pontevedra, Spain J. Fernández-López, CINAM-Lourizán, Ap. 127, 36080 Pontevedra, Spain Journal European Journal of Forest Research Online ISSN 1612-4677 Print ISSN 1612-4669