Woody species in resource‐rich microrefugia of granite outcrops display unique functional signatures

Refugia are key environments in biogeography and conservation. Because of their unique eco‐evolutionary formation and functioning, they should display distinct functional trait signatures. However, comparative trait‐based studies of plants in refugia and non‐refugia are lacking. Here, we provide a comparison between resource‐rich (putative microrefugia for species preferring mesic habitats under increasing aridity) and resource‐impoverished woodlands (non‐refugia) around two granite outcrops in south‐western Australia. We measured and compared six functional traits (bark thickness, foliar δ¹³C, foliar C:N, leaf dry matter content, plant height, specific leaf area) in four woody species. We performed multiple‐trait, multiple‐species and single‐trait, within‐species analyses to test whether plants in resource‐rich habitats were functionally distinct and more diverse than those in the surrounding resource‐impoverished woodlands. We found that species in resource‐rich woodlands occupied larger and distinct multiple‐trait functional spaces and showed distinct single‐trait values (for specific leaf area and bark thickness). This suggests that plants in resource‐rich woodlands can deploy unique and more diverse ecological strategies, potentially making these putative microrefugia more resilient to environmental changes. These findings suggest that species in microrefugia may be characterised by unique functional signatures, illustrating the utility of comparative trait‐based approaches to improve understanding of the functioning of refugia.     

Macrofungi diversity in cork-oak and holm-oak forests in Andalusia (southern Spain); an efficient parameter for establishing priorities for its evaluation and conservation

In this work, the fungal diversity of holm-oak and cork-oak woodlands in southern Spain is studied in order to analyse the macrofungi component and its ecological characteristics, as well as to establish priorities for its conservation. For this, we have compiled published as well as unpublished data, and applied compositional analysis and statistical methods (basic statistics, non-parametric and multivariate analyses). Priority areas were selected based on complementarity analysis. As a result, 838 taxa were recorded, 78.6% in cork-oak and 76.4% in holm-oak forests, with 55.1% in common. The ratio of mycorrhizal to saprophitic species indicated that cork-oak woodlands present a higher diversity and conservation degree of its macrofungal community than holm-oak woodlands, since the mycorrhizal component is more important for the conservation of these forests (due to nutritional relations). Both forests types appear well differentiated in the multivariate analysis. In the complementarity analysis, with only one site, we recorded 40% of the total species encountered. The percentage increased to 80% with four sites. This type of approach, by highlighting the important areas for conservation of fungal diversity, constitutes a powerful tool to optimise conservation efforts.     

Lichens — the biodiversity value of western woodlands

Summary

The Atlantic broad-leaved woodlands of Britain are of international renown for their lichen floras. They are inhabited by 517 lichens, representing 28.3% of the total lichen flora and 73.2% of all British woodland lichens, and they are the main habitat for 165 species. Of these, 31 have a marked southern distribution and do not reach Scotland, whereas 26 species are found in Scotland, but not England or Wales. Their British Red-listed species are outnumbered by the 86 species for which Britain has International Responsibility.

Within the Atlantic broad-leaved woodlands, only 30 lichens show a preponderance for oak. With the exception of some ancient oakwoods in southern England, a high lichen biodiversity is rarely dependent on a dominance of oak in the woodland canopy, more usually it is the result of a long ecological continuity, often a varied tree and shrub composition, a varied canopy density, and good air quality. Consequently, the oak stands within former ‘industrial’ woodlands have a much lower lichen biodiversity compared with woodlands that have a history as ‘pasture woodland’ or, as with some ravine woodlands, have otherwise escaped intensive management.

The life-history of an oak tree is considered in relation to the niches it provides for lichen colonisation with time. Some management scenarios are provided with the enhancement of the lichen interest of former ‘industrial’ oakwoods as an objective.     

Species-area curves and growth-form spectra for some herb-rich woodlands in western Victoria,Australia

Species-area curves are presented for three woodlands with herbaceous understoreys in western Victoria. Australia. Up to 93 species of vascular plant were recorded from 128 m². making these woodlands one of the richest terrestrial vegetations recorded from temperate Australia. Species richness at this scale is comparable with that recorded from kwongan (sclerophyllous shrubland) in south-western Australia. Up to 45 species were recorded from 10 m². At this scale the woodlands are the richest terrestrial vegetation recorded from Australia, and among the richest in the world, being comparable with the renowned chalk grasslands of Europe. The growth-form spectra of these woodlands differ dramatically from those of other species rich communities in temperate Australia due to the abundance of herbs and dearth of woody species. In contrast to species rich woodlands in Israel and California, perennial herbs rather than annuals predominate. Although the woodlands studied are protected in conservation reserves, regional floristic surveys are required to determine the geographic extent, floristic variability and conservation status of herb-rich woodlands in Victoria.     

The macrolepidoptera of farm woodlands: determinants of diversity and community structure

The Farm Woodland Scheme, which provided incentives to convert agricultural land to timber production, contained an implicit assumption that farm woodlands produce important benefits for wildlife. The moth fauna of 18 farm woodlands in the Vale of York was surveyed between May and November 1991. The aims were twofold. The first was to determine if there were benefits for moth species diversity. The second was to ascertain whether concepts of island biogeography and the plant species richness of the woods were related to the moth species composition.Eleven families, 214 species and over 16 000 individuals of moths were recorded. Classification of the species presence/absence matrix indicated that small woods (less than 1ha) did not have characteristic woodland moth communities. Woods larger than 5ha were judged to be more valuable for the long-term conservation of woodland moth diversity. The best predictor of moth species richness was the herbaceous plant species richness within woodlands. Species richness of the family Geometridae was positively related to woodland area, as well as to woodland shape (compact shapes being preferable to elongated shapes). Characteristic woodland species are influenced by isolation (less isolated woods being richer in species). The implications of different powers of dispersal between moth families are discussed. Farm woodlands will be of more value for the conservation of the Macrolepidoptera if they are large, compact and incorporate remnants of existing woodland with extant herbaceous vegetation. These should be factors which are taken into consideration when providing incentives to establish and manage farm woodlands.     

Mid to late Holocene vegetation and land use history in the Weald of south-eastern England: multiple pollen profiles from the Rye area

The High Weald is an unusually well-wooded area in southern England. A high proportion of this woodland is ancient, being formerly exploited as seasonal pasture and coppice. Multiple pollen profiles from the Rye area have been used to elucidate the origins of this cultural landscape. By combining sites with small and large pollen source areas, both local and regional patterns of vegetation change have been determined. The mid-Holocene Tilia-dominated woodlands were subjected to temporary clearance as early as the Neolithic. This woodland was more extensively exploited over a ca. 700 year period from the beginning of the Bronze Age. The main elements of the modern landscape (woodland, pasture and limited cultivation) can be traced back to a more intensive phase of human activity, which commenced in the late Bronze Age. A regional increase in Fagus sylvatica pollen ca. 750 B.C. probably reflects the use of the Wealden woods for pasturage. There is no palynological evidence that the fuel demands of the Roman iron industry resulted in widespread woodland destruction. The early Anglo-Saxon period appears to have been one of land-use continuity, with a second increase in Fagus pollen at ca. A.D. 700 corresponding to historical evidence for the presence of wood-pastures in the Weald.     

New evidence of unexpectedly high animal density and diet diversity will benefit the conservation of the Critically Endangered western ringtail possum

A comprehensive and contemporary understanding of habitat and resource requirements has been critical to the conservation of multiple taxa and ecosystems globally. Until recently, much of the ecological knowledge that contributes to conservation priorities and strategies for the Critically Endangered western ringtail possum (Pseudocheirus occidentalis) was largely derived from decades‐old observations in peppermint (Agonis flexuosa) and marri‐jarrah (Corymbia calophylla and Eucalyptus marginanta) woodlands in the northern parts of the species range. These observations do not account for more recent evidence of their flexible use of habitat resources in other regions of its range. This may represent a significant conservation opportunity for the species through the identification of additional habitats that warrant protection. In a region where knowledge of their ecology is scarce, we used scat analysis and quantitative spotlighting to determine the diet and density of western ringtail possums in three vegetation types: peppermint, sheoak (Allocasuarina fraseriana) and marri‐eucalypt (C. calophylla, E. marginanta and Eucalyptus staerii) woodlands. Given the species’ reported dependence on peppermint woodlands and dominant canopy species for food sources, we hypothesised that western ringtail possums would be most abundant in this habitat type and that their diet would comprise the foliage of few (≤2 species) canopy species. We found western ringtail possums consumed a higher diversity of plant species than expected (8–14), exhibited dietary preference for non‐dominant canopy species and were present in all sampled vegetation types at substantially higher densities than previously recorded for the region (as high as 17 possums ha^?1). Our results confirm (i) the western ringtail possum is flexible in its use of habitat resources and (ii) the significant conservation value of sheoak and marri‐eucalypt woodlands in the southernmost portion of its distribution.     

An overview of the ecology,management and conservation of Australia’s temperate woodlands

Summary Australia’s temperate woodlands are environments of cultural and ecological importance and significant repositories of Australia’s biodiversity. Despite this, they have been heavily cleared, much remaining vegetation is in poor condition and many species of plants and animals are threatened. Here, we provide a brief overview of key issues relating to the ecology, management and policy directions for temperate woodlands, by identifying and discussing ten themes. When addressing issues relating to the conservation and management of temperate woodlands, spatial scale is very important, as are the needs for a temporal perspective and a complementary understanding of pattern and process. The extent of landscape change in many woodland environments means that woodland patches, linear networks and paddock trees are critical elements, and that there can be pervasive effects from ‘problem’ native species such as the Noisy Miner (Manorina melanocephala). These consequences of landscape change highlight the challenge to undertake active management and restoration as well as effective monitoring and long‐term data collection. In developing approaches for conservation and management of temperate woodlands, it is essential to move our thinking beyond reserves to woodland conservation and management on private land, and recognise the criticality of cross‐disciplinary linkages. We conclude by identifying some emerging issues in woodland conservation and management. These include the need to further develop non‐traditional approaches to conservation particularly off‐reserve management; the value of documenting approaches and programmes that demonstrably lead to effective change; new lessons that can be learned from intact examples of temperate woodlands; and the need to recognise how climate change and human population growth will interact with conservation and management of temperate woodlands in future decades.     

Co‐benefits of planting species mixes in carbon projects

The carbon market offers a unique opportunity to achieve large‐scale ecological restoration of degraded agricultural landscapes. Here, we outline some of the benefits of planting mixes of native species rather than monocultures in carbon plantings as a step towards creating biodiverse carbon‐rich forests and woodlands in Australia. We highlight the gaps in our knowledge and emphasise the importance of setting benchmarks for carbon projects to maximise their potential to deliver co‐benefits such as habitat provision for wildlife. On the whole, we are optimistic that ongoing refinement of joined biodiversity conservation and carbon credit initiatives will help to develop a carbon market that can drive ecological restoration of Australian agricultural landscapes.     

Relative value of riparian woodlands in landscapes with different forest cover for medium-sized Iberian carnivores

This study analyses the role of riparian woodland in the conservation of five common carnivore species as compared with other non-riparian habitats according to woodland cover on the landscape scale (>60, 20–35 and <15% on 20 × 20-km surface area). I hypothesised that the importance of riparian woodlands in carnivore conservation on the regional scale would be greater in landscapes with low forest cover than in those with intermediate or high forest cover. To test this hypothesis, in each landscape type I sampled five riparian forests and 10–15 non-riparian habitats and recorded species richness and frequency of occurrence (number of sampled sites with species presence/total sampled sites) in both habitat types. The presence of (or use by) species at each particular sampling site was recorded using sign-surveys (search for scats and badger dens). The relative importance of riparian and non-riparian habitats in each landscape type was analysed by comparing species richness and frequency of occurrence for each species. Comparison of species richness and frequency of occurrence between landscape types indicate that riparian woodlands are important habitats in all landscape contexts. However, in accordance with the initial hypothesis, riparian woodlands are essential for carnivore conservation in the most deforested areas. Any agricultural or development policy should take into account the need to maintain and preserve riparian woodlands in landscapes, especially in intensively cultivated landscapes.     

Vegetation and songbird response to land abandonment: from landscape to census plot

While intensification of human activities and its ecological effects in many natural areas have recently received much attention, land abandonment in marginal areas is still the largely ignored side of a process rooted in the same socioeconomic context. Decreasing human impact in marginal rural areas often triggers a recovery of seminatural vegetation. Over a period of 25 years, we studied the changes in landscape and vegetation structure that followed land abandonment in a traditional Mediterranean mosaic of crops, grasslands, shrublands and woodlands, and assessed their effects on songbird occurrence and distribution. We combined an analysis of vegetation changes based on aerial photo interpretation with an analysis of bird censuses from 1978, 1992 and 2003 at two spatial scales: landscape and census plot (respectively 2800 and 3 ha). The perceived temporal changes in the vegetation were scale dependent. At the landscape scale, open habitats tended to disappear and woodlands matured. The contrasts in vegetation structure that defined habitat patches at the onset of the study tended to disappear. There was an overall shift of the bird community in favour of woodland species. At the scale of the census plot, however, the colonization by woody vegetation of patches formerly characterized by a homogeneous grass cover increased the local diversity of the vegetation, at least temporarily. Of seven species dependent on open habitats, the occurrence rate of five species significantly decreased, whereas it increased for two species: woodlark (Lulula arborea) and melodious warbler (Hippolais polyglotta). This increase was linked to the transitional increase in local vegetation diversity. In patches originally dominated by woodlands, local vegetation diversity decreased as woody vegetation expanded into clearings. The occurrence rate significantly increased for seven species relying on closed woodlands, while it decreased for two woodland species. As most species of high conservation profile in the Mediterranean are tied to open or to heterogeneous transitional habitats, these trends raise questions concerning their persistence in the future.     

“Ghosts of the past”: flightless saproxylic weevils (Coleoptera: Curculionidae) are relict species in ancient woodlands

Historic maps show that the Central European landscape was influenced by exploitive human land-use during the middle ages and in the following centuries. A mixture of ancient woodlands, which survived the period of woodland destruction, and recent woodlands, which were established after 1800, cover about 10% of the study area in NW Germany today. Weevils (Coleoptera: Curculionidae) of the subfamily Cryptorhynchinae with the genera Acalles, Kyklioacalles, Ruteria and of the subfamily Molytinae, tribe Acicnemidini with the genus Trachodes are all flightless and possibly influenced by landscape history. The aims of this investigation are (1) to examine the spatial distribution of flightless saproxylic weevils in ancient and recent woodlands in NW Germany and (2) to test the frequency of possible relict species in relation to historical and current woodland size. Based on a field study in 29 deciduous woodlands and species records in collections and literature, six flightless saproxylic weevils were found to be associated with ancient woodlands in NW Germany. None of these were recorded in any of the 14 recent woodlands studied. The frequency of these relict species is correlated with historical, but not with current, woodland size. Distribution maps for Lower Saxony and data on the phenology of the relict species are presented. These weevils are relict species of ancient woodland, because they were unable to colonise isolated woods that were established after 1800. All of them are dependent on dead or dying wood for larval development. The results show that ancient broadleaved woodlands with long-lasting habitat continuity are of high conservation value for invertebrate species such as saproxylic weevils.     

Documenting Biogeographical Patterns of African Timber Species Using Herbarium Records: A Conservation Perspective Based on Native Trees from Angola

In many tropical regions the development of informed conservation strategies is hindered by a dearth of biodiversity information. Biological collections can help to overcome this problem, by providing baseline information to guide research and conservation efforts. This study focuses on the timber trees of Angola, combining herbarium (2670 records) and bibliographic data to identify the main timber species, document biogeographic patterns and identify conservation priorities. The study recognized 18 key species, most of which are threatened or near-threatened globally, or lack formal conservation assessments. Biogeographical analysis reveals three groups of species associated with the enclave of Cabinda and northwest Angola, which occur primarily in Guineo-Congolian rainforests, and evergreen forests and woodlands. The fourth group is widespread across the country, and is mostly associated with dry forests. There is little correspondence between the spatial pattern of species groups and the ecoregions adopted by WWF, suggesting that these may not provide an adequate basis for conservation planning for Angolan timber trees. Eight of the species evaluated should be given high conservation priority since they are of global conservation concern, they have very restricted distributions in Angola, their historical collection localities are largely outside protected areas and they may be under increasing logging pressure. High conservation priority was also attributed to another three species that have a large proportion of their global range concentrated in Angola and that occur in dry forests where deforestation rates are high. Our results suggest that timber tree species in Angola may be under increasing risk, thus calling for efforts to promote their conservation and sustainable exploitation. The study also highlights the importance of studying historic herbarium collections in poorly explored regions of the tropics, though new field surveys remain a priority to update historical information.     

Response of Orthoptera communities to succession in alluvial pine woodlands

During the past 150 years forest management has dramatically altered in Central European woodlands, with severe consequences for biodiversity. Light forests that fulfilled variable human demands were replaced by dark high forests that function solely as wood plantations. In the Alps, by contrast, open woodlands are still present because the traditional land use as wood pasture has remained and physiographical conditions favour natural dynamics. The aim of our study was to investigate the effects of succession on the Orthoptera communities of alluvial pine woodlands in the northern Alps. Orthoptera showed a clear response to succession, with each successional stage harbouring a unique assemblage. The influence of succession on species richness and abundance were identical: The values were highest in the intermediate and lowest in the late seral stage. The diversity and abundance peak in the mid-successional stage probably reflects a trade-off between favourable ambient temperatures for optimal development and sufficient food, oviposition sites and shelter against predators. Food shortage and easy access for predators seemed to be limiting factors in the early successional stage. In contrast, in the late successional stage adverse microclimatic conditions probably limit Orthoptera occurrence. Although all three successional stages of the pine woodlands are relevant for conservation, the early and mid-successional stages are the most important ones. Conservation management for Orthoptera in this woodland type should aim at the reintroduction of cattle grazing and the restoration of the natural discharge and bedload-transport regimes of the alpine rivers.     

Bryophytes as indicators of ancient woodlands in Schleswig-Holstein (Northern Germany)

Ancient woodlands, with their long ecological continuity, frequently harbor a high number of typical, rare and threatened species, and are therefore of particular importance for nature conservation. To pinpoint these habitats, a common application is the use of plants as “ancient woodland indicators”. The occurrence of these particular species allows for evaluating the continuity of woodland cover in time. While lists of ancient woodland vascular plants have been derived for many regions, the identification and use of bryophytes as ancient woodland indicators has been widely neglected. This is a bit surprising because certain woodland bryophytes are very sensitive to varying environmental conditions or changes in land management. It therefore appeared promising to compile an ecologically grounded list of ancient woodland indicator bryophytes for practical use.In this study, we present a set of ancient woodland indicator bryophytes based on the analysis of datasets from the North German federal state of Schleswig-Holstein. To compile this list, we systematically evaluated the bryophyte distribution data from floristic surveys in relation to ancient woodland cover data from state-wide inventories. In this way, we were able to determine ancient woodland bryophytes using consistent and repeatable statistical methods.The presented list of 31 ancient woodland indicator bryophytes is ecologically sound and corresponds well with data from the sparse literature. We could distinguish two groups of ancient woodland indicator bryophytes. The first group is linked to base-rich, semi-natural deciduous woodlands with high soil and air humidity. The second group comprises acidophilic bryophytes that occur not only in acidic beech and oak woods, but also in acidic mixed or coniferous forests on ancient woodland sites. Apart from the ancient woodland indicator bryophytes, we could identify one group of recent woodland bryophytes and four groups of bryophytes that are more or less indifferent with respect to woodland continuity.Finally, we provide recommendations for the application of ancient woodland indicator bryophytes in nature conservation practice. Management suggestions for the conservation of the typical bryophyte diversity of ancient semi-natural woodlands are also given.     

The effect of woodland area on avian community composition in a fragmented southern UK landscape and associated management recommendations

ABSTRACT

Capsule: Smaller woodlands not only support fewer species but also show different avian community composition due to loss of woodland interior and an increase in edge habitat.

Aims: To use observed community composition changes, rather than traditional total species richness-area relationships, to make area-specific management recommendations for optimizing woodland habitat for avian communities in fragmented landscapes.

Methods: 17 woodlands were selected in Oxfordshire, UK, with areas between 0.2 and 120 ha. Three dawn area searches were conducted in each woodland between 1st April and 28th May 2016 to record encounter rates for each species. The impact of internal habitat variation on woodland comparability was assessed using habitat surveys.

Results: Woodlands with area less than 3.6 ha showed a significant positive relationship between total avian species richness and woodland area. Woodlands with area over 3.6 ha were all consistent with a mean (± se) total richness of 25.4?±?0.6 species, however the number of woodland specialists continued to increase with woodland area. Woodland generalists dominated the total encounter rate across the area range, however the fractional contribution of woodland specialists showed a significant positive correlation with woodland area, while the fractional contribution of non-woodland species significantly decreased. Non-woodland species numbers peaked in mid-sized woodlands with enhanced habitat heterogeneity.

Conclusions: Community composition analysis enabled more targeted recommendations than total species richness analysis, specifically: large woodlands (over 25?ha) in southern UK should focus conservation efforts on providing the specific internal habitats required by woodland specialists; medium-sized woodlands (between approximately 4 and 25?ha) should focus on promoting internal habitat variety, which can benefit both woodland species and non-woodland species of conservation concern in the surrounding landscape; small woodlands (under 4?ha) should focus on providing nesting opportunities for non-woodland species and on improving connectivity to maximize habitat for woodland generalists and facilitate movement of woodland specialists.     

Erasing a European biodiversity hot-spot: Open woodlands,veteran trees and mature forests succumb to forestry intensification,succession, and logging in a UNESCO Biosphere Reserve

Open woodlands are among the biologically richest habitats of the temperate zone. Although open woodlands were much more common in the past and covered large areas of Europe, their original cover and magnitude of their loss remain mostly unknown. Here, we quantify the loss of open woodlands and assess the potential for their restoration in an internationally protected biodiversity hot-spot, floodplain woodlands of lower Thaya and March rivers of Dolní Morava UNESCO Biosphere Reserve in Czech Republic. Aerial photographs from years 1938 and 2009 were used to analyse changes in forest canopy closure across an area of 146 km² and separately for 270 ha of nature reserves found in the area. Forestry maps and aerial photographs were used to analyse changes in forest age structure. Between 1938 and 2009, expansion of closed-canopy forest reduced open woodlands cover from 41% to 5.7% of total wooded area, or 68.5% to 14.1% in the state reserves respectively. Logging has led to a decrease in mature forest cover from 45% to 26% between 1990 and 2009. State reserves prevented logging, but not open woodlands loss. The magnitude of open woodlands loss parallels that of tropical habitats, but has gone unabated by nature conservation. Opportunities to restore open woodlands and conserve associated biodiversity in the internationally protected (e.g. UNESCO, Natura 2000), mostly state-owned, woodlands are being compromised by rapid logging. Our results also point to the low efficiency of international conservation measures in post-communist members of European Union.     

The effects of urban or rural landscape context and distance from the edge on native woodland plant communities

The increasing rate of urban sprawl continues to fragment European landscapes threatening the persistence of native woodland plant communities. The dynamics of woodland edges depend on the characteristics of woodland patches and also on landscape context. Our aim was to assess the extent of edge influences on the understorey vegetation of small native woodlands in rural and urban landscapes. The study was carried out in two cities of north-western France. Ten comparable woodlands, each of about 1.5 ha, were surveyed; five were situated adjacent to crops and five adjacent to built-up land. Vascular plant species were recorded in 420 3 × 3 m plots placed at seven different distances from the edge (from 0 to about 45 m from the edge). Soil pH, light levels, level of disturbance and tree and shrub cover were also recorded. Plant species were first classified as non-indigenous or indigenous and then three groups of indigenous species were distinguished according to their affinity for forest habitat (forest specialists, forest generalists and non-forest species). We inferred certain ecological characteristics of understorey vegetation by using Ellenberg values. An inter-class correspondence analysis was carried out to detect patterns of variation in plant community composition. Linear mixed models were used to test the effects of adjacent land use, distance from the edge and their interactions on the species richness of the different groups and on the ecological characteristics of vegetation. Total species richness, richness of forest generalists and of non-forest species decreased from edge to interior in both urban and rural woodlands. The number of non-indigenous species depended mainly on urban–rural landscape context. Urban woodland edges were not as rich in forest specialists as rural edges. More surprisingly, the number of forest specialists was higher in rural edges than in rural interiors. Community composition was mainly affected by urban–rural context and to a lesser degree by the edge effect: the community composition of urban edges resembled that of urban interiors whereas in rural woodlands vegetation near edges (up to 10 m) strongly differed from interiors with a pool of species specific to edges. Urban woodland vegetation was more nitrophilous than rural vegetation in both edges and interiors. A major difference between urban and rural vegetation was the distribution of basiphilous species according to distance from the edge. Generally edge vegetation was more basiphilous than interior vegetation however the presence of basiphilous species fell off quickly with distance from the edge in rural woodlands (in the first 10–15 m) and more slowly (from 25 m onwards) in urban woodlands. This pattern was linked to variation in measured soil pH. As regards the conservation of flora in small native woodlands, it appeared that invasion of exotic and non-forest species was currently limited in both urban and rural landscape contexts but might pose problems in the future, especially in urban woodlands. Forest species were not negatively affected by the edge effect and indeed edges seemed to provide important habitats for this group. Hence conservationists should pay particular attention to the protection of edges in urban woodlands.     

Evaluating the benefits of CAP reforms: Can afforestations restore bird diversity in Mediterranean Spain?

Current Common Agricultural Policy (CAP) subsidies in the Mediterranean region tend to prioritize afforestation on former arable land with oaks rather than pines because pine plantations would maintain lower biological diversities than native forests. Nevertheless, no thorough evaluations of the conservation values of pine plantations as compared to oak remnants have been carried out to date. We analyze the diversity and conservation value of bird assemblages breeding in 200 remnants of Holm oak Quercus ilex woodlands and 82 mature (>50-year-old) pine plantations in central Spain, a Mediterranean region mostly devoted to arable farming. Species–area relationships were compared between forest types. The conservation value of bird assemblages was assessed using the “Species of European Conservation Concern” (SPEC) classification of Burfield and van Bommel [(2004). Birds in Europe: Populations estimates, trends and conservation status. Cambridge: BirdLife International]. Overall numbers of bird species maintained by oak and pine archipelagoes were rather similar, but species–area relationships differed between forest types. Intercepts were higher in oak fragments, whereas slopes were steeper in pine plantations. Small oak fragments held more species (mainly Mediterranean Sylvia warblers) than plantations, whereas large plantations held more species than large oak remnants. Differences in species–area relationships seemed to be due to differences in vegetation structure, especially understorey shrub cover and tree height and cover. We recorded nine SPECs, all exclusive (6) or near-exclusive (3) to oak woodlands, although such woodlands do not appear to be critical for their conservation. Hence, we conclude that pine afforestations have played a role for maintaining and restoring forest bird communities in the farming landscapes of central Spain. Promoting large and shrubby plantations would enhance their conservation value for breeding birds, together with promoting growth, regeneration and expansion of Holm oak remnants by means of set-aside measures previous or alternative to oak reafforestation. The increasing importance of non-commercial as compared to commercial values of Mediterranean forests would justify subsidizing the proposed policy.     

Geographical distribution and habitat occurrence of the Water Shrew (Neomys fodiens) in the Weald of South-East England

A survey of 96 sites in a range of riparian habitats in the catchments of five rivers during June–August 1998 used the bait tube method to investigate the geographical distribution and habitat occurrence of Water Shrews (Neomys fodiens) in the Weald of South‐East England. Water Shrews were found at 42% of sites, and were widely distributed in all river catchments except the Mole. They occurred in many riparian habitats, including rivers, streams, canals and ditches, with a range of physical and biotic characteristics. There were no signs of habitat avoidance in response to human disturbance but Water Shrews were absent from the river catchment with lowest water quality. Logistic regression analysis was used to model the effect of habitat variables on the presence of Water Shrews, with current speed, water depth, bank incline and bank‐side vegetation identified as important variables. Fast‐flowing shallow waters had a significant positive effect on their presence, whereas scarce herbaceous vegetation and a bank of low incline had a significant negative effect. These habitat variables appear to be reliable indicators of the probability of finding Water Shrews at a particular site, and have implications for habitat management and conservation.