ALBERT

Description: Forests, Vol. 9, Pages 170: Managing the Early Warning Systems of Invasive Species of Plants, Birds, and Mammals in Natural and Planted Pine Forests Forests doi: 10.3390/f9040170 Authors: María Martínez-Jauregui Mario Soliño Jesús Martínez-Fernández Julia Touza Plantations with alien forest species could be a major way for invasive plant and animal species to become introduced and naturally established in a territory, but the sensitivity of plantations with native forest species to invasive plant and animal species is still unknown. This paper studies the probability of the presence and the richness of invasive species of three different taxa (plants, birds, and mammals) in pine forests of southwestern Europe. To do so, the relative contribution from natural and planted forests is analysed to explain the presence and the richness of invasive species in 3950 cells (10 km × 10 km) covering Spain after controlling for the possible effects of variables related to geography, climate, land use, landscape, and human pressure on the environment. Our results show that man’s influence on the establishment of invasive species is notable. However, those forests that are the most intensely managed by man, such as pine plantations with native species, seem less susceptible to the establishment and propagation of invasive species. Reasons may be found in those planted pine forests being closely monitored, controlled, and managed by man. Therefore, it is argued that efforts related to the early warning systems of invasive species should be focused on natural pine forests.

Description: Locating potential tree-planting sites and analyzing tree canopy cover is important in the planning and management of urban forests. This paper reports the quantification of potential planting sites as well as tree canopy cover in the urban area of Mexico City, estimated by means of SPOT (Satellite Pour l’Observation de la Terre) 6 satellite images and a supervised pixel-based classification approach. Results showed an estimated area of 3100.7 ha of potentially useful sites, including places with bare soil and grass-covered areas such as median strips, roundabouts and parks. An average tree canopy cover of 10.6% and an average impervious surface of 79.2% for the 15 boroughs were also analyzed. The area of potential planting sites would represent a 5% gain for the current tree canopy cover if it were to be planted. With an overall accuracy of 92.4%, the use of both images from the SPOT 6 sensor and the classification approach proved to be appropriate for obtaining thematic covers in the urban environment of Mexico City.

Description: We carried out morphological and dimensional analysis of the detritic elements deposited in the galleries of two termite species of the Kalotermitidae family present in Spain known as drywood termites (Cryptotermes brevis (Walker, 1853) and Kalotermes flavicollis (Fabricius, 1793)). This was in order to gauge the possibility of differentiating the species only on the basis of debris observation and analysis. Ten samples from six different geographical sources were analyzed and measured. Significant statistical differences were found between these two termite species in all measured parameters, and multivariate statistical models, able to predict species on the basis of dimensional measurements, were developed, with a degree of success higher than 75%. The most important dimensional differences were length and width, as well as the variable hexagonal shape of the cross-section of the detritic elements. The detritic elements of both species had a variable form of a hexagonal prism with slightly concave faces, and with pointed or rounded ends. Those of the Cryptotermes brevis species were significantly larger, less elongated, and had a smaller concavity on the faces of the prism. Color was found to be particularly variable in both species, and was not useful. Nevertheless, the debris of Kalotermes flavicollis was markedly “dirty” (mixed with other wood remains).

Description: In this study, dynamic hardness tests on solid and engineered wood flooring specimens of Eucalyptus globulus Labill. and Eucalyptus grandis W. Hill ex Maiden hardwoods were performed because nowadays, these fast-growing hardwoods are still scarcely employed for this use. Furthermore, another two examples of hardwood commonly applied on wood flooring, Quercus robur L. and Hymenaea courbaril L., were also tested. To compare their properties, a dynamic impact hardness test based on the impact of steel balls, with several diameters, and drop heights was developed. Accordingly, 120 solid wood flooring specimens and 120 engineering wood flooring specimens were producing with these four hardwood species. Dynamic impact tests were made with three steel balls of different diameters (30–40–50 mm), and they were carried out from five different drop heights (0.60–0.75–0.90–1.05–1.20 m). The impact of the steel ball drew the size of the footprint on the surface and this mark was measured with a digital caliper for both dimensions, diameter and depth, as footprint diameter (FD) and indentation depth (ID). Data from 3000 samples, corresponding to 120 different individual groups (4 species × 3 ball diameters × 5 drop height × 2 floor type) were analyzed. Results indicated that the variability of ID (CV between 19.25–25.61%) is much greater than the values achieved for FD (CV between 6.72–7.91%). Regarding the fast-growing hardwood species tested, E. globulus showed a similar behavior to traditional hardwood applied on wood flooring in Europe, Q. robur, and it could be a promising growth in the flooring industry. However, E. grandis showed the worst values compared to traditional hardwood in all test configurations.

Description: Traditional agroforestry systems are recognized as having great importance for providing multiple benefits for local communities all over the world, especially in tropical countries. Thanks to their multifunctional role, they can support small farmers, contribute to hydrogeological risk reduction, water regulation, preservation of soil, agrobiodiversity and landscape, as well as being examples of mitigation and adaptation towards climate change. The Globally Important Agricultural Heritage Systems (GIAHS) programme of the Food and Agriculture Organization (FAO) aims to identify agricultural systems of global importance, preserving landscape, agrobiodiversity and traditional knowledge, through dynamic conservation principles. The Sabana de Morro is a traditional agroforestry system located in El Salvador based on cattle grazing in pastures with the presence of Crescentia alata and Crescentia cujete trees, locally called Morro or Jícaro. We documented the main characteristics of this system, that has never been deeply studied, in the Municipality of Dolores, in accordance with the five GIAHS criteria, and through detailed land use mapping, to assess the relations between landscape structure, agrobiodiversity and traditional silvopastoral practices. Sabana de Morro proved to be based on strong interactions between trees, cattle and farmers. The pulp of the Morro fruits is eaten by grazing cattle, completing their feeding and giving a peculiar taste to the locally produced cheese. Morro trees provide shade for the animals while cattle contribute by spreading their seeds that also take advantage of the manure. Results show that this agroforestry system contributes to the preservation of a rich agrobiodiversity and of the traditional landscape. At the same time, it supports local farmers’ livelihood and is consistent with the aim of the GIAHS programme, even if further surveys and research are needed to assess the real possibility of the inclusion in this FAO programme.

Description: Most populations of Scots pine in Spain are locally adapted to drought, with only a few populations at the southernmost part of the distribution range showing maladaptations to the current climate. Increasing tree heights are predicted for most of the studied populations by the year 2070, under the RCP 8.5 scenario. These results are probably linked to the capacity of this species to acclimatize to new climates. The impact of climate change on tree growth depends on many processes, including the capacity of individuals to respond to changes in the environment. Pines are often locally adapted to their environments, leading to differences among populations. Generally, populations at the margins of the species’ ranges show lower performances in fitness-related traits than core populations. Therefore, under expected changes in climate, populations at the southern part of the species’ ranges could be at a higher risk of maladaptation. Here, we hypothesize that southern Scots pine populations are locally adapted to current climate, and that expected changes in climate may lead to a decrease in tree performance. We used Scots pine tree height growth data from 15-year-old individuals, measured in six common gardens in Spain, where plants from 16 Spanish provenances had been planted. We analyzed tree height growth, accounting for the climate of the planting sites, and the climate of the original population to assess local adaptation, using linear mixed-effect models. We found that: (1) drought drove differences among populations in tree height growth; (2) most populations were locally adapted to drought; (3) tree height was predicted to increase for most of the studied populations by the year 2070 (a concentration of RCP 8.5). Most populations of Scots pine in Spain were locally adapted to drought. This result suggests that marginal populations, despite inhabiting limiting environments, can be adapted to the local current conditions. In addition, the local adaptation and acclimation capacity of populations can help margin populations to keep pace with climate change. Our results highlight the importance of analyzing, case-by-case, populations’ capacities to cope with climate change.

Description: Fusarium circinatum Nirenberg & O’Donnel is listed among the species recommended for regulation as quarantine pests in Europe. Over 60 Pinus species are susceptible to the pathogen and it also causes disease on Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) and species in genera such as Picea and Larix. The European Food Safety Authority considers the probability of new introductions—via contaminated seeds, wood material, soil and growing substrates, natural means and human activities—into the EU very likely. Due to early detection, constant surveillance and control measures, F. circinatum outbreaks have officially been eradicated in Italy and France. However, the global spread of F. circinatum suggests that the pathogen will continue to be encountered in new environments in the future. Therefore, continuous surveillance of reproductive material, nurseries and plantations, prompt control measures and realistic contingency plans will be important in Europe and elsewhere to limit disease spread and the “bridgehead effect”, where new introductions of a tree pathogen become increasingly likely as new environments are invaded, must be considered. Therefore, survey programs already implemented to limit the spread in Europe and that could be helpful for other EU countries are summarized in this review. These surveys include not only countries where pitch canker is present, such as Portugal and Spain, but also several other EU countries where F. circinatum is not present. Sampling protocols for seeds, seedlings, twigs, branches, shoots, soil samples, spore traps and insects from different studies are collated and compiled in this review. Likewise, methodology for morphological and molecular identification is herein presented. These include conventional PCR with a target-specific region located in the intergenic spacer region, as well as several real-time PCR protocols, with different levels of specificity and sensitivity. Finally, the global situation and future perspectives are addressed.

Description: The fungal pathogen Fusarium circinatum (Nirenberg and O’ Donnell) is the causal agent of pine pitch canker (PPC) disease, which seriously affects conifer species in forests and nurseries worldwide. In Europe, PPC is only established in the Iberian Peninsula; however, it is presumed that its range could expand through the continent in the near future. Infection caused by this fungus requires open wounds on the tree, including physical damage caused by insects. Therefore, a relationship probably occurs between PPC and a wide variety of insects. The aim of this review is to outline the taxonomic and ecological diversity of insect species with high potential association with F. circinatum in Europe and elsewhere. The insects were classified as vectors, carriers and wounding agents according to the association level with the PPC disease. In addition, we discuss the insect-mediated spreading of PPC disease in relation to the different phases of forest stand development, from seeds and seedlings in nurseries to mature stands. Lastly, to improve our predictive capacities and to design appropriate intervention measures and strategies for controlling disease dissemination by insects, variables such as geographic location, time of the year and host species should be considered. Our review provides a framework of the multiple factors that regulate the insect–host interactions and determine the success of the infection.

Description: In semi-arid regions, afforestation with fast-growing species cultured with low irrigation can be an effective approach for environmental protection. An experiment was conducted to evaluate the stem biomass production of Paulownia in a semi-arid climate and clay soils under contrasting low-irrigation and fertilization treatments. The stem biomass at the stand level was estimated by applying allometric equations fitted in sample resprouts and inventory data. The results show that biomass production improved when either irrigation or fertilizer was added, but the combination of a higher dose of irrigation and fertilization did not lead to the highest biomass production; thus water availability was the main factor controlling biomass production. Under the higher dose of irrigation, the absence of a fertilizer effect would be due in part to the fertile soil, which could supply sufficient nutrients for Paulownia growth at the higher level of soil moisture. The stem biomass estimated ranged from 2.14 to 4.50 t×ha−1 (lower irrigation dose without fertilization, and higher irrigation with fertilization). The greater production was similar to other studies in the Mediterranean area receiving more irrigation. Thus, this study permitted us to understand the potential of Paulownia to provide biomass in semi-arid environments with low irrigation due to water use restrictions.