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Human–wildlife conflicts may have devastating consequences for fauna due to targeting by humans of wildlife populations suspected to have predated livestock. Suspicion of depredation of extensively raised livestock by vultures in Europe has triggered public administration-led forensic investigations intended to distinguish between predation and scavenging in order to compensate farmers for attacks on their livestock. In this study, gross and histological analyses were carried out on suspected cases of domestic animal depredation by griffon vultures (Gyps fulvus) over a 1-year period. Fifty-eight animals were affected (n = 41, suspected depredation), including domestic cattle (75.9%), sheep (22.4%) and a goat (1.7%). All the adults affected were female and most cases of suspected depredation occurred during the peripartum period (56%). Histological investigations distinguished between post-mortem (84% of diagnostic samples) and ante-mortem (16% of diagnostic samples) cases, and gross examinations revealed significant differences (P ≤ 0.002) between ante-mortem, post-mortem and non-diagnostic samples. This study highlights the need to optimize sampling protocols to increase the success of forensic studies. The forensic investigations presented here may be applied to resolve human–wildlife conflicts involving not only vultures but other endangered carnivores and contribute to human–wildlife coexistence in rural areas by protecting the interests of both the livestock sector and endangered species. [ABSTRACT FROM AUTHOR]

The area covered by plantations of hybrid poplar in Europe is increasing greatly because of the high profitability of these trees. However, the productivity varies widely depending on nutritional status, and it is therefore essential to identify the limiting nutrients. The aims of this study were (a) to identify the main nutrients limiting the growth and vitality of monoclonal poplar ( Populus × euramericana) plantations and (b) to develop a means of early detection of nutrition-related problems in growth, based on visual crown conditions (crown transparency, VCT, and visual crown discoloration, VCD). The study was carried out in one of the most suitable areas for this species in Southern Europe. Thirty-two Populus × euramericana (clone I-214) stands displaying different levels of decline were selected for study, and tree growth, nutritional status (soil properties and foliar nutrient concentrations) and crown conditions were assessed. The stands, which were growing in soils with high contents of coarse fragments, displayed low growth rates, poor crown conditions and deficiencies in Fe, B, N, P, K, and to a lesser extent, Zn and Cu. The deficiencies increased with the age of the stand, presumably because of the higher nutrient demand in older trees. Visual crown conditions were related to growth rates and nutritional status. Predictive models were developed to relate crown conditions to the nutritional status identified by analysis of soil properties and foliar concentrations of nutrients. [ABSTRACT FROM AUTHOR]

Abstract: This study proposes stand level models for estimating biomass yield, total energy and carbon sequestration in Eucalyptus globulus and Eucalyptus nitens plantations, on the basis of measurements made in 131 plots established at the usual range of initial forest densities for southwestern Europe. The timber volume, total aboveground biomass, logging residue biomass, crown biomass, carbon in aboveground biomass and soil organic layer, energy in aboveground biomass, energy in logging residue biomass and usable cellulose yield were represented in the form of isolines (taking mortality into account) and plotted against dominant height. These variables were calculated and compared with previously published data on two silvicultural options for short rotation forestry, one destined for bioenergy production and the other consisting of the standard silviculture regime applied to both species in southern Europe, considering the average site index for each species. Yield levels were higher in E. nitens than in E. globulus for all variables because of faster diameter increment at similar densities. The total yield in terms of biomass was 13.9–14.6Mgha−1 y−1 for E. globulus and 20.4–21.5Mgha−1 y−1 for E. nitens. Energy in aboveground biomass ranged between 233 and 245GJha−1 y−1 for E. globulus and 345 and 364GJha−1 y−1 for E. nitens, carbon accumulation rate in aboveground biomass and soil organic layer was 6.9–7.2Mgha−1 y−1 for E. globulus and 12.7–13.5Mgha−1 y−1 for E. nitens, and usable cellulose was 5.7–5.9Mgha−1 y−1 for E. globulus and 9.0–10.1Mgha−1 y−1 for E. nitens. It was found that 50% increments in the initial density result in only marginal increments in biomass and usable cellulose yields. [Copyright &y& Elsevier]

Abstract: Managed forests often differ substantially from undisturbed forests in terms of tree structure and diversity. By altering the forest structure, management may affect the C stored in biomass and soil. A survey of 58 natural stands located in the south-westernmost limit of European beech forests was carried out to assess how the C pools are affected by the changes in tree structural diversity resulting from past management. The mean tree density, basal area and the number of large trees found in unmanaged forests were similar to those corresponding to virgin beech forests in Central Europe, whereas large live trees were totally absent from partially cut stands. Analysis of the Evenness index and the Gini coefficient indicated high structural diversity in the three stand types. The results of the Kolmogorov–Smirnov test used to compare the diameter distributions of each group revealed significant differences between stand types in terms of distributions of total tree species and of Fagus sylvatica. The mean C stocks in the whole ecosystem – trees, litter layer and mineral soil – ranged from 220 to 770Mgha−1 (average 380Mgha−1). Tree biomass (above and belowground), which averaged 293MgCha−1, constituted the main C pool of the system (50–97%). The statistical test (Kolmogorov–Smirnov) revealed differences in the distribution of C pools in tree biomass between unmanaged and partially cut stands. As a consequence of the presence of large trees, in some unmanaged stands the C stock in tree biomass was as high as 500–600MgCha−1. In the partially cut stands, most of the C was mainly accumulated in trees smaller than 20cmdbh, whereas in unmanaged stands the 30% of tree C pool was found in trees larger than 50cmdbh. Furthermore, many unmanaged stands showed a larger C pool in the litter layer. The C content of mineral soils ranged from 40 to 260MgCha−1 and it was especially high in umbrisols. In conclusion, the implementation of protective measures in these fragile ecosystems may help to maintain the highly heterogeneous tree structure and enhance the role of both soils and trees as long-term C sinks. [Copyright &y& Elsevier]