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45Evidence from an international survey in the Atlantic biogeographic region of Europe 46indicates that chronic nitrogen deposition is reducing plant species richness in acid 47 grasslands. Across the deposition gradient in this region (2 to 44 kg N ha -1 yr -1 ) species 48 richness showed a curvilinear response, with greatest reductions in species richness when 49 deposition increased from low levels. This has important implications for conservation 50 policies, suggesting that to protect the most sensitive grasslands resources should be 51 focussed where deposition is currently low. Soil pH is also an important driver of species 52 richness indicating that the acidifying effect of nitrogen deposition may be contributing to 53 species richness reductions. The results of this survey suggest that the impacts of nitrogen 54 deposition can be observed over a large geographical range.

Summary1. Disturbances and resource availability are key factors affecting plant diversity in managed forests. As disturbance regimes vary among silvicultural systems and may simultaneously affect different types of resources, effects on biodiversity can be unpredictable. 2. We compared the effects of two silvicultural systems on understorey plant diversity, including species composition, structural attributes and functional organization. One hundred and thirty-five phytosociological relevés were sampled from 27 forest stands managed under either a traditional coppice-with-standards (CWS, n = 12) or a 'close-tonature' selective cutting system (SC, n = 15), over similar edaphic conditions. Important environmental factors affecting vegetation were deduced using Ellenberg indicator values. Structural diversity was described using traditional indices of α and β diversity. Guilds were defined within the local pool of species using a set of 14 traits and their relationship with silviculture was assessed using correspondence analysis. 3. Post-logged CWS stands share some compositional and structural characteristics with selectively cut stands, including high species richness and a dominance of early successional species. However the species pool for all coppicing areas was higher than for selectively cut areas, suggesting that the high disturbance frequency occurring in the latter may progressively eliminate the most sensitive species. 4. Functional diversity strongly differs between the two systems. Although it is conserved through the silvicultural cycle in the coppice-with-standards system, some guilds were lacking in selectively cut stands. The most negatively impacted guilds were tree and shrub saplings, prostrated ruderals, shade-tolerant perennials and vernal geophytes. The latter two comprise 'true forest species' which may also be considered as 'coppicingmaintained species'. To reach the same values of guild richness (i.e. number of guilds) or redundancy (i.e. proportion of the maximal species richness within each guild), larger areas were required in SC compared with CWS systems. 5. In the SC system, the high proportion of light reaching the forest floor induced a spectacular spread of blackberries Rubus fruticosus agg., which decreased species richness. It also caused shifts in guild composition: graminoids and ferns grew strongly to the detriment of true forest species. 6. Synthesis and applications . Our results suggest long-term negative effects of selective cutting on both structural and functional plant diversity, compared with coppice-withstandards. Cutting intervals are shorter than recovery times, so that early successional species-dominated communities are maintained. Vernal geophytes and shade-tolerant perennials seem to be limited by the frequency of disturbance rather than by the severity of disturbance. We conclude that, from a biodiversity point of view, this 'close-to-nature' system does not cope with the objective of sustainable forest management. The rotations currently in use do not match n...

Conflicts between biodiversity conservation and human activities are becoming increasingly apparent in all European landscapes. The intensification of agricultural and silvicultural practices, land abandonment and other land uses such as recreation and hunting are all potential threats to biodiversity that can lead to conflicts between stakeholder livelihoods and biodiversity conservation. To address the global decline in biodiversity there is, therefore, a need to identify the drivers responsible for conflicts between human activities and the conservation of European biodiversity and to promote the management of these conflicts. Here, the drivers of biodiversity conflicts are analysed in a European context for five habitat types: agricultural landscapes, forests, grasslands, uplands and freshwater habitats. A multidisciplinary approach to conflict management is described, with active stakeholder involvement at every stage of conflict identification and management as well as a range of other approaches including stakeholder dialogue and education, consumer education, improvement of political and legislative frameworks, financial incentives, and planning infrastructure.