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Summary 1. The effect of extreme climate events on ecosystems is an important driver of biotic responses to climate change. For forests, extreme drought has been linked to negative effects such as large-scale mortality and reduced primary production. However, the response of plant communities to extreme drought events remains poorly understood. 2. We used mortality data from a long-term monitoring programme in the core of the focal species’ ranges, in combination with annual growth data from tree-rings, to study the effect of, and recovery from, an extreme drought event. We examined both the intraspecific and interspecific drought response and explored how differential responses affect competitive dominance between the dominant species Fagus sylvatica and Quercus petraea. 3. Mortality for the most drought-susceptible species, F. sylvatica, occurred alongside a temporary reduction in competition-induced mortality of Q. petraea, resulting in the long-term alteration of the relative abundance of the two species. 4. Significant intraspecific variation occurred in post-drought recovery in surviving F. sylvatica, with two distinct cohorts identified. A prolonged recovery period was coupled with the failure to regain pre-drought growth levels in this species, whereas for Q. petraea, no severe drought impacts were observed. This species instead experienced competitive release of growth. 5. Our results demonstrate that ecosystem responses to extreme drought can involve rapid, nonlinear threshold processes during the recovery phase as well as the initial drought impact. These sudden changes can lead to the reordering of dominance between species within communities, which may persist if extreme events become more frequent.

As a consequence of long-term deforestation, woodland cover has been drastically reduced in the United Kingdom. The remaining woodland consists mainly of small, highly fragmented woodland patches within farmland. A number of agri-environment schemes aim to increase the amount and quality of woodland on agricultural land, but there is limited information on associations between moths and woodland characteristics which can be used to produce practical recommendations for woodland creation and management. We studied micro- and macromoth communities in woodland patches within farmland to assess the effects of woodland vegetation character and patch configuration. In addition, we measured the influence of the surrounding landscape to assess the potential importance of a landscape-scale management approach for moth conservation. In general, high tree species diversity and a high proportion of native tree species were related to higher moth abundance and species richness; there was a negative impact of grazing. Moth abundance and richness were higher in large woodland patches located close to other woodlands. Woodlands of compact shapes (with proportionally less edge exposed to the surrounding matrix) had higher numbers of ‘woodland species’, which were associated with woodland core habitat. Small woodland patches can potentially maintain relatively high moth abundance and richness, depending on their shape and proximity to other woodlands. Woodland extent was the most important landscape parameter influencing moths, mostly at relatively small spatial scales (6500 m); macromoth ‘woodland species’ were influenced by woodland extent at larger spatial scales (61500 m) and are more likely to benefit from a landscape-scale management approach. Our results have important implications for the design and management of woodland patches of high conservation value within agricultural land. 2012 Elsevier Ltd. All rights reserved.

© 2016 The Author(s)The aim of our study was to determine variation in the response of radial growth in $\textit{Fagus sylvatica}$ L (European Beech) to climate across the species full geographical distribution and climatic tolerance. We combined new and existing data to build a database of 140 tree-ring chronologies to investigate patterns in growth–climate relationships. Our novel meta-analysis approach has allowed the first investigation of the effect of climate on tree growth across the entire geographical distribution of the species. We identified key climate signals in tree-ring chronologies and then investigated how these varied geographically and according to mean local climate, and by tree age and size. We found that the most important climate variables significantly correlated with growth did not show strong geographical patterns. Growth of trees in the core and at the southern edge of the distribution was reduced by high temperature and low precipitation during the growing season, and by high temperatures in the previous summer. However, growth of trees growing in warmer and drier locations was more frequently significantly correlated with summer precipitation than other populations. Additionally, the growth of older and larger trees was more frequently significantly correlated with previous summer temperature than younger and smaller trees. Trees growing at the south of the species geographical distributions are often considered most at risk from climate change, but our results indicate that radial growth of populations in other areas of the distribution is equally likely to be significantly correlated with summer climate and may also be vulnerable. Additionally, tree-rings from older trees contain particular growth–climate relationships that are rarely found in younger trees. These results have important implications for predicting forest carbon balance, resource use and likely future changes to forest composition across the continent.

Agricultural expansion has led to the widespread destruction of habitats and the creation of fragmented landscapes. Woodland has been severely affected by habitat loss; remaining woodland is often highly fragmented and degraded, immersed in an agricultural matrix. Woodland is one of the most important habitats for bats because it offers roosting and feeding opportunities for many species. A number of agri-environment schemes aim to increase the amount and quality of woodland on agricultural land; however, little is known about how woodland character relates to bat abundance/activity and recommendations for woodland creation and management for foraging bats are scarce. We studied temperate bat communities and examined bat foraging activity and relative abundance (and insect prey availability) in 34 woodland fragments in agricultural landscapes using two complementary methods (acoustic monitoring and trapping assisted by an acoustic lure). We evaluated the relative importance of woodland vegetation character, patch configuration and surrounding landscape in order to assess the importance of local- vs. landscape-scale woodland management to bat populations. Bat abundance and activity were influenced by both local and landscape-level attributes. At the local scale, woodland vegetation character appeared more important than patch configuration. High activity levels of aerial hawkers (e.g. Pipistrellus species) were related to low tree densities and an open understory, while gleaning species (e.g. Myotis bats) showed the opposite trend. Areas of cluttered vegetation were associated with high insect (mostly Diptera) abundance and could act as sources of prey for certain bat species. Bats' responses to the surrounding landscape depended on species mobility. For relatively low mobility species (e.g. Pipistrellus pygmaeus), local woodland character was more important than the landscape context, whereas the opposite was observed for higher mobility species (e.g. Pipistrellus pipistrellus and Myotis bats). Higher bat activity levels were observed in small and isolated woodland fragments, and in sparsely wooded landscapes. This may reflect a more intensive use of woodland in landscapes where this habitat is scarce, where woodland creation should be prioritised. Woodland management and creation schemes should encourage habitat heterogeneity to fulfil the requirements of different bat species. © 2013 Elsevier B.V.

Rising temperatures and increasing drought severity linked to global climate change are negatively impacting forest growth and function at the equatorial range edge of species distributions. Rapid dieback and range retractions are predicted to occur in many areas as temperatures continue to rise. Despite widespread negative impacts at the ecosystem level, equatorial range edges are not well studied, and their responses to climate change are poorly understood. Effective monitoring of tree responses to climate in these regions is of critical importance in order to predict and manage threats to populations. Remote sensing of impacts on forests can be combined with ground-based assessment of environmental and ecological changes to identify populations most at risk. Modelling may be useful as a ‘first-filter’ to identify populations of concern but, together with many remote sensing methods, often lacks adequate resolution for application at the range edge. A multidisciplinary approach, combining remote observation with targeted ground-based monitoring of local susceptible and resistant populations, is therefore required. Once at-risk regions have been identified, management can be adapted to reduce immediate risks in priority populations, and promote long-term adaptation to change. However, management to protect forest ecosystem function may be preferable where the maintenance of historical species assemblages is no longer viable.