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Spiders play a key role in forest food webs, where they regulate decomposer populations and may act as predators of pests and disease vectors. Spider community composition is determined in part by vegetation structure. Therefore, the exclusion of large mammals, such as deer and wild boar, through wildlife fencing may affect the composition of spider communities and their prey in forest ecosystems. Web-building spiders and their prey were hand-collected in plots that had been fenced for three years, as well as adjacent unfenced plots in a mixed temperate forest in north-eastern Germany. Additionally, spiders in the leaf litter were sampled in fenced and unfenced subareas by sieving litter. Wildlife fencing did not significantly affect spider densities or community composition per microhabitat. However, fencing affected the cover of different microhabitats significantly as there was a higher density of larger trees and higher leaflitter cover in fenced plots while there was a higher percentage of bare ground and deadwood in unfenced plots. Spider communities and their prey composition differed significantly between microhabitats (deciduous trees, coniferous trees, dead wood, understory vegetation, leaf litter) independent of fencing. Thysanoptera prey was mainly caught by spiders on coniferous trees and in the understory vegetation. Heteroptera prey were captured most frequently in the understory vegetation while Hymenoptera (excl. Formicidae) prey were mostly caught on deciduous trees. Several spider species showed a preference between deciduous and coniferous trees in the mixed forest. Wildlife fencing alters the vegetation structure of mixed forests and has indirect effects on spider communities and their role in forest food webs due to alteration of microhabitat availability. [ABSTRACT FROM AUTHOR]

• Flower fields can have similarly positive effects on bat activity as hedgerows. • AES can promote bats in agricultural landscapes and may provide suitable foraging habitats for bats in homogenous landscapes. • Critically endangered bat species were found flying above all our AES. Agri-environment schemes (AES) have become important tools for farmland biodiversity conservation, providing suitable habitats, resources, and connectivity within the agricultural landscapes. Bats are rarely studied in relation to AES effectiveness in contrast to birds, even though their presence and activity as biological control agents on insects, especially pest species, can be important for agricultural crops. While the role of hedgerows for bat occurrence and activity, as well as for their prey's diversity and abundance has been widely studied, the role of other AESs such as flower fields remains unclear. We monitored the activity of the main functional groups (edge, narrow and open space foragers) using ultrasound recorders, as well as potential prey abundances using light traps, across 35 study sites representing different AES in Central Germany from late July to September 2018. The sampled AES consisted of annual flower fields, mixed flower fields (with annual and biennial vegetation), perennial flower fields (sown every 5 years), hedgerows (surrounded by meadows and agricultural fields), and were compared to winter wheat (control) in a balanced design. Bat activity over hedgerows increased threefold for edge space foragers and sevenfold for narrow space foragers compared to wheat fields. Compared to wheat fields, narrow space forager activity increased fourfold over perennial flower fields, threefold over annual and twofold over mixed flower fields. This group's activity over hedgerows also increased almost threefold compared to mixed flower fields. However, the number of feeding buzzes and prey abundance did not differ significantly between AES. We detected foraging group-specific differences in bat activity between the studied AES. Thus, to promote bats in agricultural landscapes and to ensure their biological control services, it is important to establish more AES, such as hedgerows and flower fields, to increase their diversity and connectivity in intensively used agricultural landscapes. [ABSTRACT FROM AUTHOR]

For the conservation of biodiversity, heathlands present important ecosystems throughout Europe. The formerly widespread habitats are nowadays restricted to small and isolated remnants. Without land use heathland vegetation undergoes succession and, in addition, the increasing amount of atmospheric nitrogen deposition has resulted in an encroachment of grasses. In the present study we analysed the effects of succession and grass encroachment on Orthoptera in a coastal heathland on the Baltic island of Hiddensee, Germany. Vegetation, microclimate, soil humidity and Orthoptera were sampled in the five main stages of heathland succession, namely grey dunes, dwarf-shrub heath, grassy heath, heath with shrubs, and birch forest. Vegetation and environmental parameters showed strong differences among the successional stages. Orthoptera species richness was highest in transitional stages. The high proportion of grasses offer favourable habitat conditions for graminivorous, chorto- and thamnobiont species. Orthoptera density was highest in grey dunes. Threatened and specialised species were restricted to the young stages grey dunes and dwarf-shrub heath. Hence, in order to maintain a high diversity of Orthoptera in heathlands, maintaining different successional stages is of critical importance and this should be integrated into heathland management practices. [ABSTRACT FROM AUTHOR]

The globally threatened Aquatic Warbler Acrocephalus paludicola is an umbrella species for fen mires and is at risk of extinction in its westernmost breeding population due to severe habitat loss. We used boosted regression trees to model Aquatic Warbler habitat selection in order to make recommendations for effective management of the last remnant habitats. Habitat data were collected in the years 2004–2006 in all remaining breeding sites in Pomerania (eastern Germany and western Poland) as well as in recently abandoned sites. Models were validated using data from similar Aquatic Warbler habitats in Lithuania. The probability of occurrence of Aquatic Warblers in late May/early June was positively associated with low isolation from other occupied sites, less eutrophic conditions, a high proportion of area mown early in the preceding year, high availability of vegetation 60–70 cm high, high prey abundance and high habitat heterogeneity. Early summer land management is needed in the more productive sites to prevent habitat deterioration by succession to higher and denser vegetation. As this also poses a serious threat to broods, management that creates a mosaic of early and late used patches is recommended to preserve and restore productive Aquatic Warbler sites. In less productive sites, winter mowing can maintain suitable habitat conditions. Aquatic Warbler-friendly land use supports a variety of other threatened plant and animal species typical of fens and sedge meadows and can meet the economic interests of local land users. [ABSTRACT FROM AUTHOR]

Brownfield sites contribute significantly to urban biodiversity due to their high spatio-temporal dynamics and their transient character. Plant species richness is, among other factors, contingent on vegetation structure. In this study, we examined plant species richness, vegetation height, vegetation density and soil parameters of a chronosequence of urban brownfield sites in Bremen and Berlin, Germany. These parameters were linked to successional age using single and multiple linear regression. Most biotic and abiotic variables differed significantly between sites with and without brick rubble in the soil, indicating a strong effect of site history on vegetation development. Soil parameters of the sites were not clearly linked to site age. Vegetation height and density increased significantly over time. Additionally, height and density increased with soil phosphorus content and water permeability of the soil, whilst plant available water only contributed to the model of vegetation density. Species richness increased with vegetation height but decreased with vegetation density. This indicates that species richness is maximised when a community comprises a mixture of early and mid-successional species. The results suggest that high plant species richness on sandy brownfield sites can be achieved by strong disturbances at an interval of 5 (±2) years. However, limiting soil resources can prolong this interval considerably. Management aiming to maximise plant species richness in urban brownfield sites should therefore take into account the interplay between soil resources and site age. [ABSTRACT FROM AUTHOR]

Despite great efforts in European nature conservation, semi-natural habitats such as calcareous grasslands are still suffering considerable declines due to abandonment. Shrub cutting and subsequent grazing or mowing are effective restoration measures to counteract the adverse effects of management cessation. Here, for the first time, we used leafhoppers (Auchenorrhyncha) as bioindicators to assess the conservation value of restored calcareous grasslands. We compared environmental conditions and leafhopper assemblages of 21 restored grasslands and 21 regularly managed sites (control) within the largest area of calcareous grasslands in the northern part of Germany. Furthermore, we applied Generalised Linear Mixed-effects Models (GLMM) to assess the effects of environmental parameters on species richness of leafhoppers within the restored grasslands. After a period of three to eight years, the restoration measures had led to species-rich leafhopper assemblages, including both habitat specialists and threatened species. However, we still found clear differences in leafhopper composition compared to the control. Within the restored grasslands, a pronounced field layer and an increased number of host plants positively affected species richness. In conclusion, the restored grasslands form open fringe-like habitat structures that clearly enhance the conservation value of calcareous grasslands by (i) harbouring numerous exclusive (indicator) species leading to a higher leafhopper diversity at the habitat level and (ii) by providing habitats for several habitat specialists which occurred only rarely on control grasslands. In order to maintain or even increase the biodiversity of calcareous grasslands, we recommend a combination of traditional grazing and small-scale shrub cutting. • First study using leafhoppers for the evaluation of calcareous grassland restoration • Restoration measures have formed open fringe-like habitat structures within calcareous grasslands. • These new habitat structures were colonized by species-rich leafhopper assemblages. • Species composition clearly differed between restored and extant calcareous grasslands. • Restored sites provided habitats for several specialised species. [ABSTRACT FROM AUTHOR]

Tidal wetlands have been increasingly recognized as long-term carbon sinks in recent years. Work on carbon sequestration and decomposition processes in tidal wetlands focused so far mainly on effects of global-change factors such as sea-level rise and increasing temperatures. However, little is known about effects of land use, such as livestock grazing, on organic matter decomposition and ultimately carbon sequestration. The present work aims at understanding the mechanisms by which large herbivores can affect organic matter decomposition in tidal wetlands. This was achieved by studying both direct animal-microbe interactions and indirect animal-plant-microbe interactions in grazed and ungrazed areas of two long-term experimental field sites at the German North Sea coast. We assessed bacterial and fungal gene abundance using quantitative PCR, as well as the activity of microbial exo-enzymes by conducting fluorometric assays. We demonstrate that grazing can have a profound impact on the microbial community structure of tidal wetland soils, by consistently increasing the fungi-to-bacteria ratio by 38-42%, and therefore potentially exerts important control over carbon turnover and sequestration. The observed shift in the microbial community was primarily driven by organic matter source, with higher contributions of recalcitrant autochthonous (terrestrial) vs. easily degradable allochthonous (marine) sources in grazed areas favoring relative fungal abundance. We propose a novel and indirect form of animal-plant-microbe interaction: top-down control of aboveground vegetation structure determines the capacity of allochthonous organic matter trapping during flooding and thus the structure of the microbial community. Furthermore, our data provide the first evidence that grazing slows down microbial exo-enzyme activity and thus decomposition through changes in soil redox chemistry. Activities of enzymes involved in C cycling were reduced by 28-40%, while activities of enzymes involved in N cycling were not consistently affected by grazing. It remains unclear if this is a trampling-driven direct grazing effect, as hypothesized in earlier studies, or if the effect on redox chemistry is plant mediated and thus indirect. This study improves our process-level understanding of how grazing can affect the microbial ecology and biogeochemistry of semi-terrestrial ecosystems that may help explain and predict differences in C turnover and sequestration rates between grazed and ungrazed systems., (© 2017 by the Ecological Society of America.)