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1. The impacts of agricultural intensification on farmland wildlife have been the subject of increasing concern, particularly over the last two decades. Population declines have occurred for a number of mammalian species, sometimes drastically so, and changes in farming practice are believed to be significant contributory factors. 2. The major policy instruments for delivering environmental benefits on farmland are agri-environment schemes. These encourage farmers to adopt more environmentally sensitive farming practices to promote farmland biodiversity. Additionally, compulsory set-aside, which reduces agricultural surplus, could also have positive impacts on wildlife. In this paper we consider some of the putative benefits of agri-environment schemes and set-aside for mammals. 3. We review how establishment and management options within agri-environment schemes and set-aside might affect habitat resources for mammals. For example, conservation headlands increase plant and invertebrate resources within the crop edge for mammals such as wood mice. Grassy field margins can support communities of smaller mammals, and hedgerows may act as important commuting and hunting routes. Their potential will depend on factors such as seed mixtures used, timing and severity of cutting, and length of time they have been in place. 4. At a farm level, habitat heterogeneity may be increased through organic agriculture, which is supported by some agri-environment schemes. Studies suggest significant benefits to mammals, including wood mice and bats. However, it is increasingly recognized that effective conservation of farmland mammals must seek solutions at the landscape scale, addressing such issues as habitat connectivity between farms. One approach may be the better targeting of scheme agreements. 5. We suggest that agri-environment schemes and set-aside can contribute to the conservation of mammals on farmland. Recent policy changes are likely to have further positive impacts on f

Previous studies suggest widespread positive responses of biodiversity to organic farming. Many of these studies, however, have been small-scale. This project tested the generality of habitat and biodiversity differences between matched pairs of organic and non-organic farms containing cereal crops in lowland England on a large-scale across a range of taxa including plants, insects, birds and bats. The extent of both cropped and un-cropped habitats together with their composition and management on a range of scales were also compared. Organic farms was likely to favour higher levels of biodiversity and indeed organic farms tended to support higher numbers of species and overall abundance across most taxa. However, the magnitude of the response differed strikingly; plants showed stronger and more consistent responses than other taxa. Some, but not all, differences in biodiversity between systems appear to be a consequence of differences in habitat quantity.

Presence of higher plant species was recorded in 1455 permanently marked quadrats located across Britain in 1978, 1990 and 1998 in a stratified, random sample of 259 1 km squares. Significant increases and decreases in frequency of each species were summarised as changes in the representation of simple traits, each of which had an established relationship with varying levels of fertility or disturbance. By testing the null hypothesis that the trait values represented among increasing or decreasing species were a random draw from the 1978 species pool, we determined the consistency of botanical change with changes in land-use in different vegetation types and landscape locations across Britain. Overall, 63% of significant changes in species occupancy were decreases and 37% increases. Trait changes were largely consistent with the impact of increased nutrient availability across vegetation types associated with inherently low fertility, such as infertile grassland, heath, bog and moorland. Linear habitats in lowland Britain saw trait changes consistent with secondary succession. Although trait changes were highly consistent with eutrophication in upland vegetation, the identity of the changing species left open the possibility that increased N deposition, sheep grazing intensity and local improvement could all have played a part. Recent changes in common plant species across Britain suggest that objectives for large-scale restoration and maintenance of plant communities must address four problems: (a) the increasing scarcity of stress-tolerant species in lowland species pools, (b) exploitation and maintenance of species populations on habitat fragments and linear features in the lowlands, (c) the spread and persistence of generalist species in upland Britain, (d) systemic nutrient enrichment in both lowland and upland environments.

The conservation and management of biodiversity requires accurate, repeatable and cost-effective monitoring techniques. In this study, a simple and rapid methodology was employed to measure the quality of different habitats for butterfly species on 10 arable farms in lowland Britain. This habitat monitoring was seven times more rapid than the traditional species-based butterfly monitoring. Data on butterfly abundance were combined with the information gathered on habitat quality at five of the farms using stepwise regression. These models had a consistently high degree of explanatory power for the summary variables of total butterfly abundance and species richness, and the functional groupings of mobile and immobile species. There was good agreement between observed and predicted estimates of species richness and abundance when the models were validated on a further five independent sites. Models to predict the abundance of 11 common butterfly species were also produced. These varied considerably in their predictive power and validity between species. The results clearly demonstrated the beneficial effects of targeted habitat creation for butterflies which is promoted under the Agri-environment Schemes, especially the recently introduced pollen and nectar seed mixtures (WM2) available under the Countryside Stewardship Scheme. The models confirmed the importance of shelter, floristically diverse field margins and the availability of nectar resources from legume species in explaining the abundance of immobile butterfly species in arable landscapes. These sources of nectar and the presence of larval host plants in the crucifer family were important factors in explaining the abundance of mobile species. The results are discussed in terms of the potential of this approach for: (i) assessing habitat quality for butterflies in intensively managed landscapes; (ii) enhancing the value of butterfly monitoring schemes in explaining changes in butterfly abundance at the site an

The need and rationale to survey, assess and continually monitor the state of ecosystems at small and large spatial scale have become understood and accepted by the educated public. Growing environmental concerns have given these activities ever greater scientific importance and political weight (Reid, 2000). Some decades ago, the growing perception of global change added the element of urgency. An important step in the development of thought and practice in floral and faunal inventories and integrated ecosystem assessment in the UK was the Countryside Survey Programme. Initially conceived as a single survey of British vegetation in 1978, it has developed into a programme of continuous assessing and monitoring vegetation, land cover, landscape features, soils, freshwaters and birds. In this special issue of the Journal of Environmental Management, we report some of the major findings of the latest phase of field surveys, known as Countryside Survey 2000, concentrating, where possible and appropriate, on the changes observed in the states of ecosystems since the previous surveys in 1978 and 1990. In the first paper, Firbank et al. introduce the Countryside Survey Programme. The development and approach are explained and some of the survey results and work experiences presented. The state of the natural environment in Great Britain are assessed and the recent changes are described in the following papers. Howard et al. look at changes in land cover, expressed in terms of Broad Habitats, and produce a comprehensive classification of the land into ecologically meaningful units. Petit et al. then describe changes affecting quality and extent of different types of field boundaries, so important for landscape quality. Smart et al. report on recorded changes in vegetation since 1990. Black et al. report results of a new element of the Countryside Survey, the first national survey of soil biodiversity in Britain. Haines-Young et al. focus on the regional aspects of changes i

Countryside Survey 2000 (CS2000) is the latest in a series of surveys designed to measure and evaluate stock and change of land cover, landscape features, freshwaters, habitats and the vegetation of Great Britain. The ideas behind CS2000 developed during the 1960s and 1970s and culminated in the first survey of vegetation and land cover in 1978. One kilometer sample squares were selected at random using an environmental stratification. Subsequent surveys took place in 1984, 1990 and 1998, revisiting the original sample locations, whilst progressively expanding in scope and sample size; CS2000 included soils, breeding birds, remotely sensed imagery, freshwater biota and hydromorphology. Countryside Survey data may be interpreted using the pressure–state–response model, by selecting indicators of process and quality, and by identifying models of expected responses to different pressures. Thus, results showing losses of hedgerows between 1984 and 1990 stimulated new protection for these features. Ideally, CS2000 data should be used to stimulate experiments to distinguish between different pressures, in order to ensure that policy and management responses are both appropriate and achievable. The experience from CS2000 may prove helpful for the design and management of other large scale monitoring programmes of ecosystems. In particular, the scope of the survey, and the use to which the data are applied, have evolved through time, and yet continuity was essential for change to be detected efficiently. These objectives were reconciled by collecting the data in a disaggregated form, allowing a high degree of flexibility in both analysis and reporting.

This paper describes how Countryside Survey 2000 (CS2000) and earlier Countryside Surveys in 1990 and 1984, can be used to develop an integrated view of the changes in land cover, landscape and biodiversity that have taken place at the regional scale in Great Britain. A particular concern is to develop an understanding of how the national patterns of stock and change are distributed across Great Britain, and whether such changes are leading to more or less regional differentiation in our landscapes and biodiversity. A further concern is how the structure of landscape is changing. A description of the major Environmental Zones that make up Great Britain is given. Analysis of the regional patterns of change observed suggests that there has been considerable geographical variation in the gains and losses of the stock of the Biodiversity Action Plan Broad Habitats. Between 1984 and 1990, in the lowlands of the south and west of England and Wales, there were significant increase in the area of the Arable and Horticultural and Broadleaved Woodland Broad Habitats, and a marked loss of Improved Grassland. Over the same period, in the uplands of England and Wales, significant losses of Acid Grassland were observed, with associated gains in Improved Grassland. The Environmental Zones in Scotland were more stable in terms of the changes in stock of Broad Habitats. In addition to the analysis of net changes in stock of the Broad Habitats, the paper provides an analysis of the exchanges of land between major cover categories or each of the Environmental Zones. In contrast to the regionally concentrated changes in habitat stock, more ubiquitous and uniform changes in habitat quality were detected between 1990 and 1998, which continue trends observed for the 1980s. The quality of freshwater habitats increased. However, there were declines in the quality for some terrestrial biotopes, as indicated by the loss of species diversity from agricultural habitats, and the gains in diversi

This report provides data analyses and initial interpretation of hedgerow data arising from Countryside Survey 2000. Data are presented from hedgerow diversity plots, D-plots; these are 30 m lengths of hedge, ten recorded at random positions within those 1 km sample squares where hedgerows were present. Woody species and gaps were recorded to estimate their contribution to the total length of hedge in each plot. Width and height of the hedge canopy base were also recorded to supplement other variables recorded as part of the standard Countryside Survey procedure. Data are also presented on hedgerow trees, observed in each square in 1990 and 1998 as either individual trees or lines of trees. A total of 2,393 D-plots were recorded on 520 squares across GB. Of these, 0.2 % contained 10 or more native woody species, while at the other extreme 14 % contained only a single woody species. Species-rich hedgerows are defined by the BAP as containing five or more species in a 30 m length, except in the north of England, upland Wales and Scotland where the number is four. We interpret this as a minimum of five species in Environmental Zones 1 & 2 (the lowlands of England and Wales) and four species elsewhere. By this interpretation, 28 % of hedgerows are species-rich in Environmental Zones 1 & 2 and 38 % in Environmental Zone 3. A total of 26% of all D-plots sampled had five or more woody species. Gaps constitute only small proportions of hedgerow length, very rarely exceeding 10 % (5 % of all D-plots had gaps accounting for up 10 % of the total length). These figures exclude the vast majority of plots that had no gaps recorded at all. Around 68 % of hedgerows were between 1 - 2m wide and in 69 %, the base of the hedge canopy was less than 0.5 m high. These figures differ little between Environmental Zones, except that Scottish hedgerows tended to be taller than those in England (although based on a much smaller sample). Around 90 % of hedgerows contained hawthorn (Crataegus m