Effects of forest management on ground-dwelling beetles (Coleoptera; Carabidae, Staphylinidae) in Central Europe are mainly mediated by changes in forest structure

Forest management is known to influence species diversity of various taxa but inconsistent or even contrasting effects are reported for arthropods. Regional differences in management as well as differences in regional species pools might be responsible for these inconsistencies, but, inter-regional replicated studies that account for regional variability are rare. We investigated the effect of forest type on the abundance, diversity, community structure and composition of two important ground-dwelling beetle families, Carabidae and Staphylinidae, in 149 forest stands distributed over three regions in Germany. In particular we focused on recent forestry history, stand age and dominant tree species, in addition to a number of environmental descriptors. Overall management effects on beetle communities were small and mainly mediated by structural habitat parameters such as the cover of forest canopy or the plant diversity on forest stands. The general response of both beetle taxa to forest management was similar in all regions: abundance and species richness of beetles was higher in older than in younger stands and species richness was lower in unmanaged than in managed stands. The abundance ratio of forest species-to-open habitat species differed between regions, but generally increased from young to old stands, from coniferous to deciduous stands and from managed to unmanaged stands. The response of both beetle families to dominant tree species was variable among regions and staphylinid richness varied in the response to recent forestry history. Our results suggest that current forest management practices change the composition of ground-dwelling beetle communities mainly by favoring generalists and open habitat species. To protect important forest beetle communities and thus the ecosystem functions and services provided by them, we suggest to shelter remaining ancient forests and to develop near-to-nature management strategies by prolonging rotation periods and increasing structural diversity of managed forests. Possible geographic variations in the response of beetle communities need to be considered in conservation-orientated forest management strategies.

A novel approach for assessing shifting cultivation dynamics in a regional conservation hotspot - insights from nort-eastern Madagascar

The north-eastern escarpment of Madagascar has been deemed a global hotspot of biodiversity due to its high levels of endemic speciesbeing heavily threatened by accelerated deforestation rates and landscape changes. The main concern for conservation of the remaining humid primary forests is the shifting cultivation practices of local smallholder farmers for rice production. According to the mainstream narrative, human population growth leads to a shortening of crop-fallow cycles and thus to the accelerated conversion of forests to agricultural land. However, little is currently known about the dynamic changes between forest and shifting cultivation systems at the regional level. Existing land cover change analyses in this area have so far only focused on binary forest to non-forest changes and have therefore failed to account for the dynamic nature of the change processes between forest and different agriculture land use systems. This can be partly explained by the significant challenge to delineate shifting cultivation systems on land cover maps using traditional remote sensing classification approaches. To address this gap we therefore applied a novel GIS approach, that was originally developed for the assessment of shifting cultivation dynamics in Laos and has so far never been applied elsewhere, to map shifting cultivation of different crop-fallow lengths as well as permanent agriculture land use at the regional level. Change analyses of land use maps between 1995 and 2011 allowed us to comprehend the general trends of land use trajectories and their spatial variation. This more detailed understanding of land use change dynamics is key to plan for successful interventions to slow forest loss while at the same time improving local livelihoods. We further believe that this approach holds great potential for conservation monitoring in this resource-rich but povertyprone conservation hotspot.

Deforestation and forest degradation monitoring and assessment of biomass and carbon stock of lowland rainforest in the Analanjirofo region, Madagascar

Madagascar is currently developing a policy and strategies to enhance the sustainable management of its natural resources, encouraged by United Nations Framework Convention on Climate Change (UNFCCC) and REDD. To set up a sustainable financing scheme methodologies have to be provided that estimate, prevent and mitigate leakage, develop national and regional baselines, and estimate carbon benefits. With this research study this challenge was tried to be addressed by analysing a lowland rainforest in the Analanjirofo region in the district of Soanierana Ivongo, North East of Madagascar. For two distinguished forest degradation stages: “low degraded forest” and “degraded forest” aboveground biomass and carbon stock was assessed. The corresponding rates of carbon within those two classes were calculated and linked to a multi-temporal set of SPOT satellite data acquired in 1991, 2004 and 2009. Deforestation and particularly degradation and the related carbon stock developments were analysed. With the assessed data for the 3 years 1991, 2004 and 2009 it was possible to model a baseline and to develop a forest prediction for 2020 for Analanjirofo region in the district of Soanierana Ivongo. These results, developed applying robust methods, may provide important spatial information regarding the priorities in planning and implementation of future REDD+ activities in the area.

Speciation reversal and biodiversity dynamics with hybridization in changing environments

A considerable fraction of the world's biodiversity is of recent evolutionary origin and has evolved as a by-product of, and is maintained by, divergent adaptation in heterogeneous environments. Conservationists have paid attention to genetic homogenization caused by human-induced translocations (e.g. biological invasions and stocking), and to the importance of environmental heterogeneity for the ecological coexistence of species. However, far less attention has been paid to the consequences of loss of environmental heterogeneity to the genetic coexistence of sympatric species. Our review of empirical observations and our theoretical considerations on the causes and consequences of interspecific hybridization suggest that a loss of environmental heterogeneity causes a loss of biodiversity through increased genetic admixture, effectively reversing speciation. Loss of heterogeneity relaxes divergent selection and removes ecological barriers to gene flow between divergently adapted species, promoting interspecific introgressive hybridization. Since heterogeneity of natural environments is rapidly deteriorating in most biomes, the evolutionary ecology of speciation reversal ought to be fully integrated into conservation biology.

Spatial isolation and genetic differentiation in naturally fragmented plant populations of the Swiss Alps

Aims The effect Of anthropogenic landscape fragmentation on the genetic diversity and adaptive potential of plant populations is a major issue in conservation biology. However, little is known about the partitioning of genetic diversity in alpine species, which occur in naturally fragmented habitats. Here, we, investigate molecular patterns of three alpine plants (Epilobium fleischeri, Geum reptans and Campanula thyrsoides) across Switzerland and ask whether Spatial isolation has led to high levels of populations differentiation, increasing over distance, and a decrease of within-population variability. We further hypothesize that file contrasting potential for long-distance dispersal (LDD) of Seed in these Species will considerably influence and explain diversity partitioning. Methods For each study species, we Sampled 20-23 individuals from each of 20-32 populations across entire Switzerland. We applied Random Amplified Polymorphic Dimorphism markers to assess genetic diversity within (Nei's expected heterozygosity, H-e; percentage of polymorphic hands, P-P) and among (analysis of molecular variance, Phi(st)) populations and correlated population size and altitude with within-populalion diversity. Spatial patterns of genetic relatedness were investigated using Mantel tests and standardized major axis regression as well as unweighted pair group method with arithmetic mean cluster analyses and Monmonier's algorithm. To avoid known biases, We standardized the numbers of populations, individuals and markers using multiple random reductions. We modelled LDD with a high alpine wind data set using the terminal velocity and height of seed release as key parameters. Additionally, we assessed a number of important life-history traits and factors that potentially influence genetic diversity partitioning (e.g. breeding system, longevity and population size). Important findings For all three species, We found a significant isolation-by-distance relationship but only a moderately high differentiation among populations (Phi(st): 22.7, 48 and 16.8%, for E. fleischeri, G. reptans and C. thyrsoides, respectively). Within-population diversity (H-c: 0.19-0.21, P-p: 62-75%) was not reduced in comparison to known results from lowland species and even small populations with < 50 reproductive individuals contained high levels of genetic diversity. We further found no indication that a high long-distance seed dispersal potential enhances genetic connectivity among populations. Gene flow seems to have a strong stochastic component causing large dissimilarity between population pairs irrespective of the spatial distance. Our results suggest that other life-history traits, especially the breeding System, may play an important role in genetic diversity partitioning. We conclude that spatial isolation in the alpine environment has a strong influence on population relatedness but that a number of factors can considerably influence the strength of this relationship.

Effects of forest management on the diversity of deadwood-inhabiting fungi in Central European forests

Land use and land use change affect deadwood amount, quality and associated biodiversity in forest ecosystems. Old growth or virgin forests, which are exceptionally rare in temperate Europe harbor more deadwood and associated fungal species than managed forests. Whether and how more recent abandonment of management, to reestablish more natural forests, affects deadwood amount and fungal diversity on deadwood is unknown. Our main aim was to compare deadwood amount, characteristics and deadwood inhabiting fungi in differently managed forest types typical for large areas of Central Europe. We sampled deadwood inhabiting fungi on 27 forest plots of 400 m2 each in three geographically distant regions in Germany. Three forest management types, namely managed coniferous, managed deciduous and unmanaged deciduous forests, were represented by nine plots each. In autumn 2008 we collected all fungal fruiting bodies on deadwood >7 cm of diameter. We found deadwood amounts and fungal species numbers in unmanaged forests to be lower than in managed forests, which we attributed to the lack of natural tree death during the short time since management abandonment of usually 10–30 years. However, rarefaction analysis among deadwood items in forest plots indicated a slightly higher species density in unmanaged forests, which may be the first signal of a positive effect on fungal species richness on deadwood after management was abandoned. Although the three study regions span a large geographical gradient, we did not detect differences in the fungal species composition or in deadwood amounts and patterns, which reflects the wide distribution of this group of organisms and points to consistent management procedures among study regions. A very clear composition difference however occurred between deciduous and coniferous wood showing species substrate specialization. We conclude that the amount of deadwood is the main driver of deadwood fungal species richness, and substrate diversity in terms of various decay degrees, deadwood tree species and deadwood size are also important. Thus, to promote species richness of deadwood fungi it is vital to enhance deadwood amounts and diversity

Herbivores equalize the seedling height growth of three dominant tree species in an African tropical rain forest

Determining the impact of insect herbivores on forest tree seedlings and saplings is difficult without experimentation in the field. Moreover, this impact may be heterogeneous in time and space because of seasonal rainfall and canopy disturbances, or ‘gaps’, which can influence both insect abundance and plant performance. In this study we used fine netting to individually protect seedlings of Microberlinia bisulcata, Tetraberlinia bifoliolata and Tetraberlinia korupensis trees (Fabaceae = Leguminosae) from insects in 41 paired gap-understorey locations across 80 ha of primary rain forest (Korup, Cameroon). For all species, growth in height and leaf numbers was negligible in the understorey, where M. bisulcata had the lowest survival after c. 2 years. In gaps, however, all species responded positively with pronounced above-ground growth across seasons. When exposed to herbivores their seedling height growth was similar, but in the absence of herbivores, M. bisulcata significantly outgrew both Tetraberlinia species and matched their leaf numbers. This result suggests that insect herbivores might play an important role in maintaining species coexistence by mitigating sapling abundance of the more palatable M. bisulcata, which in gaps was eaten the most severely. The higher ratio in static leaf damage of control-to-caged M. bisulcata seedlings in gaps than understorey locations was consistent with the Plant Vigour Hypothesis. This result, however, did not apply to either Tetraberlinia species. For M. bisulcata and T. korupensis, but not T. bifoliolata (the most shade-tolerant species), caging improved relative seedling survival in the understory locations compared to gaps, providing restricted support for the Limiting Resource Model. Approximately 2.25 years after treatments were removed, the caged seedlings were taller and had more leaves than controls in all three species, and the effect remained strongest for M. bisulcata. We conclude that in this community the impact of leaf herbivory on seedling growth in gaps is strong for the dominant M. bisulcata, which coupled to a very low shade-tolerance contributes to limiting its regeneration. However, because gaps are common to most forests, insect herbivores may be having impacts upon functionally similar tree species that are also characterized by low sapling recruitment much more widely than currently appreciated. An implication for the restoration and management of M. bisulcata populations in forests outside of Korup is that physical protection from herbivores of new seedlings where the canopy is opened by gaps, or by harvesting, should substantially increase its subcanopy regeneration, and thus, too, its opportunities for adult recruitment.

Spider Ecophysiology

With over 43,000 species, spiders are the largest predacious arthropod group. They have developed key characteristics such as multi-purpose silk types, venoms consisting of hundreds of components, locomotion driven by muscles and hydraulic pressure, a highly evolved key-lock mechanism between the complex genital structures, and many more unique features. After 300 million years of evolutionary refinement, spiders are present in all land habitats and represent one of the most successful groups of terrestrial organisms. Ecophysiology combines functional and evolutionary aspects of morphology, physiology, biochemistry and molecular biology with ecology. Cutting-edge science in spiders focuses on the circulatory and respiratory system, locomotion and dispersal abilities, the immune system, endosymbionts and pathogens, chemical communication, gland secretions, venom components, silk structure, structure and perception of colours as well as nutritional requirements. Spiders are valuable indicator species in agroecosystems and for conservation biology. Modern transfer and application technologies research spiders and their products with respect to their value for biomimetics, material sciences, and the agrochemical and pharmaceutical industries.