Countryside Survey Research Articles

Benefits of habitat restoration to small mammal diversity and abundance in a pastoral agricultural landscape in mid-Wales

Changes in agricultural practice are predicted across the UK following agricultural reform driven by government policy. The suitability of agri-environment schemes for many species is currently debated because limited quantitative data are collected. In order to understand the changes to biodiversity due to agri-environment schemes, there is a need for studies to not just compare biodiversity and species composition in and out of agri-environment areas, but to factor in the influence of temporal habitat changes. In this study, we investigate the suitability of an agri-environment initiative to support and enhance a small mammal fauna among pastoral hill farms in mid-Wales. Grazed and ungrazed woodlands, riparian habitats, and broadleaf plantations, were compared for small mammal abundance and diversity following a trapping study. Mammal diversity was similar across habitats, though abundance varied significantly. A principle component analysis identified that mammal abundance clustered into three main habitat groups separated by seral stage (early, mid, late). No relationship between mammal abundance and stock grazing was found. A canonical correspondence analysis confirmed that vegetation structure was important in explaining the distribution of captures of mammal species across the landscape. The results for habitat type, and habitat context, suggest that a mix of vegetation seral stages, reflecting a varied vegetation structure, is important to maintain small mammal diversity and abundance across the study area. Heterogeneity in structural diversity at the landscape scale is important to maintain a variety of ground-dwelling mammal species, and particularly because trends in countryside surveys show that woodlands are skewed towards late seral stages. Habitat heterogeneity can be maintained because the hill farms neighbour each other, and the farmers co-operate as a group to manage the landscape. Habitat diversity is therefore possible. These results help us to advocate, and anticipate, the benefits of groups of farms within a landscape.

Declines in forage availability for bumblebees at a national scale

We assessed national scale changes in the forage plants of bumblebees in Britain, as a means of providing quantitative evidence for the likely principal cause of declines in bumblebee species. We quantified the relative value of native and long-established plant species as forage (nectar and pollen) resources for bumblebees by collating visitation data from 14 field sites across Britain. Twentieth Century changes in range and frequency of these forage plants were assessed using data from the New Atlas of the British and Irish Flora (1930–1969 to 1987–1999) and the Countryside Surveys of Britain (1978–1998). Forage plants declined in both large-scale range and local-scale frequency between the two survey periods. These changes were of greater magnitude than changes in other native plant species, reflecting serious reductions in quality of foraging habitats for bees as well as a general decline in insect-pollinated plants. Seventy-six percent of forage plants declined in frequency within 1-km squares, including those (e.g. Trifolium pratense) of particular value for threatened bumblebee species. We consider how our findings relate to other recorded changes in the British flora, how they may help to explain declines in bumblebees and how they could contribute to a conservation strategy.

Multi-scale survey by sample-based field methods and remote sensing: A comparison of UK experience with European environmental assessments

Effective implementation of national and European policy on the environment requires the design and utilisation of multi-scale environmental monitoring and information distribution systems. To be cost effective, consistent and well supported, any environmental monitoring scheme will need to serve multiple end users. The Centre for Ecology and Hydrology (CEH), in the UK and the EU, is addressing the issues of environmental data collection at a range of different scales, creating a structure to integrate detailed field-based measurements with information from remote sensing. CEH undertakes ‘Countryside Surveys’ that comprise sample-based field surveys and land cover maps from satellite images. Integration and inter-calibration of the data for the field surveys and remotely sensed maps is creating a unified product that exploits the strengths of each. In Europe, land cover maps produced as part of the CORINE programme have a coarser spatial resolution, thus the UK contributions to CORINE are generalisations of the national products. The UK can be seen to have an integrated environmental assessment from field to European scales. The European Global Monitoring for Environment and Security (GMES) programme aims to improve ecological assessment through the development of standard products and operational delivery services at continental scales. GMES must build on programmes such as Countryside Survey and CORINE to deliver data and information for truly multi-scale, multi-use landscape level environmental applications across Europe. This paper therefore aims to describe emerging systems in the UK and the European Union to assist the collection and analysis of environmental data at a range of different scales through the integration of detailed field-based measurements with information from remote sensing.

Predicting the risk of losing parcels of semi-natural habitat to intensive agriculture

Analysis of detailed data on habitat turnover derived from the Countryside Survey of Great Britain indicates that some types of habitat conversion can be predicted. We report that parcels of semi-natural grassland were more likely to have been converted to intensive agriculture if they were large, had a high nutrient status and were in the proximity of land that has already been intensified; three variables indicating an environmental potential for intensification. Most of the conversions predicted by the models were observed (high specificity) but a substantial number of conversions were not predicted (low sensitivity), indicating that the models could be refined by integrating additional information. We suggest that the ecological and spatial characteristics of individual parcels of semi-natural habitats and their surrounding land use should be used as a basis to assess the risk of biodiversity loss in dynamic agricultural landscapes.

Integrating land-cover data with different ontologies: identifying change from inconsistency

Spatially coincident land-cover information frequently varies due to technological and political variations. This is especially problematic for time-series analyses. We present an approach using expert expressions of how the semantics of different datasets relate to integrating temporal time series land-cover information where the classification classes have fundamentally changed. We use land-cover mapping in the UK (LCMGB and LCM2000) as example data sets because of the extensive object-based meta-data in the LCM2000. Inconsistencies between the two datasets can arise from random, gross and systematic error and from an actual change in land cover. Locales of possible land-cover change are inferred by comparing characterizations derived from the semantic relations and meta-data. Field visits showed errors of omission to be 21% and errors of commission to be 28%, despite the accuracy limitations of the land-cover information when compared with the field survey component of the Countryside Survey 2000.

Estimation of deforestation rates in Great Britain

Summary Estimates of national deforestation rates are required for reporting under the United Nations Framework Convention on Climate Change (UNFCCC) and the Kyoto Protocol. The most direct record of deforestation in Great Britain (GB) is provided by Forestry Commission (FC) unconditional felling licences, which give a value of ~500 ha a ‐1 for recent years. This probably represents a minimum, as unlicensed felling will also occur but to an unknown extent. The deforestation rate can be estimated indirectly by constructing a forest area budget, assuming deforestation is the residual term remaining after the observed change in forest area is subtracted from the recorded area of newly planted forest. Independent estimates of the total GB forest area can be obtained from the FC Woodland Census, the FC National Inventory of Woodland & Trees, and the Countryside Survey. An additional independent source of estimates of the total Scottish forest area is provided by the National Countryside Monitoring Scheme (NCMS). The observed increase in total area in these data does not differ significantly from the recorded planting rate, and a statistically significant deforestation rate was not detectable. An alternative approach is to use national survey schemes, in which repeated surveys of land use are made in a set of permanent plots. Deforestation rate can be calculated as the sum of transitions from all forest classes to all non-forest classes. Both the NCMS and the Countryside Survey can be used in this way. The NCMS survey can be scaled to give a GB deforestation rate of ~1000 ha a ‐1 , whilst the Countryside Survey gives a value of ~20000 ha a ‐1 . The NCMS value is thought to be more reliable, as the afforestation rate estimated in this way agrees closely with FC figures, whilst the Countryside Survey substantially overestimates afforestation. National mapping data from the Ordnance Survey (OS) can be used in a similar way and, as the whole country is covered by a rolling programme of surveys, sampling bias should be removed. These data show a similar temporal pattern to the felling licence data, but with considerably higher deforestation rates, with a mean of 4059 ha a ‐1 and a peak at over 7000 ha a ‐1 . However, these data suggest that there was substantial conversion of forest to agricultural land (62 per cent of the total deforested area). It seems unlikely that extensive unlicensed felling would have occurred for expanding agricultural land, when there has been little economic or policy incentives to do so, and we therefore suspect that these data may overestimate rural deforestation. The best estimate of the recent deforestation rate may be obtained by combining the data from the FC unconditional felling licences (accounting for conversions to rural uses) with the OS estimate of deforestation for non-rural uses which do not generally require a felling licence. This gives a value of 1375 ha a ‐1 .

Effects of area and isolation of woodland patches on herbaceous plant species richness across Great Britain

Richness of Ancient Woodland Indicator plant species was analysed in 308 woodland patches that were surveyed during the Countryside Survey of Great Britain carried out in 1998. The Countryside Survey recorded vegetation plots and landscape structure in 569 stratified 1 km sample squares and developed a remotely-sensed land cover map of the UK. Using these datasets, we tested the hypothesis that Ancient Woodland Indicator species richness in woodland fragments was limited by patch area, shape and spatial isolation and that woodland patches located in the lowland region of Great Britain would respond differently than those in the upland region. The variation in Ancient Woodland Indicator species richness in the British lowlands (n = 218) was mainly explained by patch area and two measures of connectivity, the length of hedgerows and lines of trees in the 1 km square and the area of woodland within 500 m of the vegetation plot. By contrast, variation in Ancient Woodland Indicator species richness in the British uplands (n = 90) was related to Ellenberg scores of the vegetation communities sampled – a surrogate for habitat quality – and no significant effect of spatial structure was detected. It therefore appears that the degree of fragmentation of woodland in the British lowlands limits the distribution of Ancient Woodland Indicator species, while in the uplands, failed colonisation is a matter of habitat quality rather than a result of landscape structure.

A national perspective on recent changes in the spatial characteristics of woodland in the British landscape

In this paper, we assessed to what extent the overall increase in woodland area observed in Great Britain over the last 20 years (about 9%) has modified the distribution and spatial characteristics of woodland at the landscape level. Field mapping data recorded in 1984 and 1998 during the national monitoring programme Countryside Survey were analysed for the six main regions of Great Britain. Results indicate that, woodland patches are very dynamic features in the British landscape, hence contradicting the widely shared view that woodland are stable elements in a landscape. It also appeared that the net increase in woodland density observed across regions hid important turnovers and that a substantial number of existing woodland patches, some of them probably quite ancient, were either removed or suffered from shrinkage. Gains in woodland density resulted as much from the proliferation of newly planted patches than from the expansion of existing patches, hence a relatively limited increase in average patch size. It, therefore, appears that the increase in total area of woodland in Britain has not stopped the continuous loss of old woodland and has only led to little de-fragmentation.

Actor–network theory: a suitable framework to understand how land cover mapping projects develop?

The Countryside Surveys of 1990 and 2000 are introduced and their methodological or ontological differences described. Actor–network theory examines the processes by which individual scientific claims are supported, debated and constructed by determining the interactions, connections and activities of the actors involved. The actors and their networks for the Countryside Surveys of 1990 and 2000 are compared. Such an analysis provides a description of why science evolves. Changes in the commissioning context behind scientific results and the process by which empirical facts are established are clearly illustrated. This type of analysis goes beyond the technological developments that would be revealed if only the scientific elements were examined. This type of analysis provides a useful tool to those seeking to reconcile ontological and semantic differences between scientific data.

The development and scientific principles of an environmental classification for strategic ecological survey in the United Kingdom

A method of environmental classification has been applied twice to surveys of the whole of England, Scotland and Wales (the United Kingdom). Such experience is now being extended to the European continent. The paper draws on the unpublished working-papers of the relevant scientists and institutions in reconstructing both the motives and circumstances in which a methodology was developed in the UK for the assessment of the ecological resources of the wider countryside. The principles of strategic classification and subsequent sampling from defined strata were initially devised for broadleaved woodland, and first tested at a regional level. They drew on classical regression theory, with the environmental classification being the independent, and the vegetation or habitat the dependent, variable. The approach was linked to the development of efficient algorithms for analysis and classification, and more recently remote sensing and geographical information systems. Successive Countryside Surveys of the UK, carried out since 1978, have provided an objective measurement of the decline in the quality of vegetation and habitats. Such a statistically robust approach can be used to measure the rates of vegetation and habitat change at the strategic European level, and as an aid to devising appropriate rural-resources policies.

Changes in Land Cover and Parcel Size of British Lowland Woodlands over the Last Century in Relation to Game Management

The area and number of woodlands within landscapes managed for shooting pheasants and other lowland game birds are contrasted with those not managed for game. The study locations were sample 1-km squares from the Countryside Survey (CS), a survey of the land cover of Great Britain. Two-hundred-and-thirty-two appropriate CS squares were divided into game and non-game squares on the basis of evidence of management for game. No significant differences were found in changes in woodland area or parcel number during the periods 1984-90 and 1990-98. Twelve matched pairs of game and non-game squares were selected, and the disposition of woodland was taken from maps of the 1870s, 1940s, 1960s and 1980s, recording total area, number of woodland parcels and parcel sizes. The number of parcels of woodland in game squares increased more than that in non-game squares during the period 1960s-1980s, but mean parcel size changed little. Landscapes where management for game has taken place have retained a greater proportion of the woodland present in the 1870s. It seems that game shooting has encouraged landowners to retain existing woodlands, and to plant new ones, during the period 1960s-1980s.

Field boundaries in Great Britain: stock and change between 1984, 1990 and 1998

Field boundaries are man-made features found worldwide and their multiple functions in agricultural landscapes are now widely recognised. These landscape features have declined drastically in many developed countries as a result of agricultural intensification. In Great Britain, field boundaries are regarded as elements of particular significance in the countryside, both in term of extent and value, whether ecological, cultural, or aesthetic. The Countryside Surveys of Great Britain, a national ecological, surveillance programme initiated in the late 1970s, provides information about the change in extent and ecological condition of field boundaries. In this paper, we present the main results on field boundaries derived from the latest survey, Countryside Survey 2000. These include stock and change of boundaries for the 1990–1998 period as well as an update of the previously published 1984–1990 data. Special attention is given to the evolution of the length of hedges. Applicability of the Countryside Survey methodology to other monitoring programmes and further use of the data is discussed together with the potential ecological consequences of the changes described in the paper.

Changing landscapes, habitats and vegetation diversity across Great Britain

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 diversity in semi-natural habitats, such as Acid Grasslands, more usually associated with vegetation types that are poor in species. An important driver of qualitative change appears to be widespread nutrient enrichment from nitrogen. However, such processes are probably superimposed upon more local factors, such as changes in the way land is managed for agriculture. The importance of understanding the various drives of change for future countryside policy is emphasized.

Assessing stock and change in land cover and biodiversity in GB: an introduction to Countryside Survey 2000

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.

National-scale vegetation change across Britain; an analysis of sample-based surveillance data from the Countryside Surveys of 1990 and 1998

Patterns of vegetation across Great Britain (GB) between 1990 and 1998 were quantified based on an analysis of plant species data from a total of 9596 fixed plots. Plots were established on a stratified random basis within 501 1 km sample squares located as part of the Countryside Survey of GB. Results are primarily conveyed in terms of a classification of national land-cover into 22 mutually exclusive Broad Habitat types. Each of the fixed vegetation plots could be assigned to the Broad Habitat in which they were located in either year. Two types of analysis are reported, both based on changes in plant species composition within monitoring plots. The first examined turnover and net change between Broad Habitat types. The second quantified more subtle changes that had occurred within each Broad Habitat using a series of condition measures that summarized multivariate plant species data as a single scalar value for each plot at each time. There are major difficulties in using uncontrolled, large-scale surveillance data to unravel causal linkages and no attempt was made to quantitatively partition variation among competing causes. However, it was clear that results were broadly consistent with environmental drivers known to have operated prior to and during the survey interval. Large-scale vegetation changes could be summarized in terms of shifts along gradients of substrate fertility and disturbance. Changes implied increased nutrient availability across upland and lowland ecosystems while, in lowland landscapes, linear features and small biotope fragments saw a marked shift to species compositions associated with greater shade and less disturbance.

Sampling Broad Habitat change to assess biodiversity conservation action in Northern Ireland

A habitat monitoring programme, the Northern Ireland Countryside Survey, carried out by the University of Ulster for the Department of the Environment for Northern Ireland, is described. It was based on a random sample of quarter kilometer grid squares, stratified by multivariate land classification. Estimates of change in habitat area between 1987–1992 and 1998 are presented and used to assess policy-related priorities for biodiversity conservation action in widespread habitats in Northern Ireland (NI). The basis of the assessment is Broad Habitats, a classification developed as part of the United Kingdom (UK) Biodiversity Action Plan. Improved Grassland, Neutral Grassland and Bog Broad Habitats occupy the largest area of NI, which holds a large proportion of the UK Neutral Grassland and Fen Marsh and Swamp Broad Habitat resource. The greatest net area increases with time were in Improved Grassland (33%), Coniferous Woodland (12%) and Broadleaved, Mixed and Yew Woodland (9%). The greatest net area decreases were in Neutral Grassland (−32%), Arable and Horticulture (−25%), Fen, Marsh and Swamp (−19%), Bog (−8%) and Calcareous Grassland (−7%). These changes are a function of agriculture, public and private forestry, building construction and peat cutting for fuel. The Key biodiversity issue is seminatural Broad Habitat loss, in particular, Neutral Grassland and Fen, Marsh and Swamp, highlighting the lack of effective action for protecting biodiversity in the countryside as a whole. The extent to which current land use is shown to be driving change, indicates that biodiversity conservation action through implementing landscape-scale agri-environment measures could deliver major biodiversity gains. The reliable information on recent changes, provided by the Northern Ireland Countryside Survey, has been used to guide conservation planning. Future re-survey will allow the effectiveness of the conservation strategy as it applies to the countryside as a whole, to be determined. As decisions on land use increasingly have a strong European dimension, concerted action for protecting biodiversity in the countryside as a whole is needed. This would be promoted by a structured sampling approach, based on standard habitat mapping procedures.

Assessing soil biodiversity across Great Britain: national trends in the occurrence of heterotrophic bacteria and invertebrates in soil

An assessment of the biodiversity of soils was a component of the Countryside Survey 2000 (CS2000). This was the first integrated survey of soil biota and chemical properties at a national scale. A total of 1052 soil samples were collected across Great Britain during CS2000 and analysed for a range of soil microbial and invertebrate characteristics resulting in the production of a series of robust datasets. A principal objective was to use these datasets to investigate relationships between soil biota and environmental factors such as geographical location, vegetation, land use, land cover, soil type and pollutant levels as first stages in characterising the inherent biodiversity of British soils and investigating the potential of soil biodiversity as indicators of soil health at a regional or national scale. Preliminary results for culturable heterotrophic, invertebrate taxa, Acari, Collembola and Oribatid mites are presented here to illustrate the nature of the data collected and the patterns of soil biodiversity in relation to large-scale regional, vegetation and soil characteristics across the British countryside.

General principles of monitoring land cover change based on two case studies in Britain and Denmark

There is a well-established need to monitor land use and ecological change so that appropriate policies for the maintenance and enhancement of biodiversity can be developed. By building such exercises around sound scientific principles the reliability of the results can be quantified and policy makers can have confidence that they are genuinely independent. This paper describes two case studies of the development of such systems, the Small Biotope project of Denmark and the Countryside Survey project of Great Britain. These systems illustrate the problems involved in studies at the landscape level and the way satisfactory results can be achieved. Monitoring is considered to be effectively repeated surveillance and needs especially strict protocols to separate real change from the artefacts of sampling. The lessons to be learnt from these studies are summarised as a number of guidelines.

A comparison of the ecological quality of land between an English agri-environment scheme and the countryside as a whole

A survey of 451 Countryside Stewardship Scheme (CSS) agreements was carried out across England in 1998–1999 to characterise the ecological quality of the land. The land within the agreements was mapped using the UK Biodiversity Action Plan Broad and Priority Habitats and the vegetation of the agreements was sampled using random quadrats. By far the most widespread Broad Habitat was Improved Grassland, accounting for around 50% of all agreement land. Of this, the majority was semi-improved. Priority Habitats accounted for 15% of all agreement land (equivalent to around 18,500 ha). In addition to the 15%, there was also land within habitat mosaics containing one or more Priority Habitat. The analysis of vegetation revealed that 53% of all randomly-placed quadrats were categorised as Infertile Grassland and 24% as Fertile Grassland. Survey data were compared with results from the Countryside Survey 2000, a national assessment of vegetation undertaken in 1998. In the lowland areas of England, CSS land had a much higher proportion of grassland habitats and was much more likely to be typical of low fertility situations than the countryside as a whole. In the marginal uplands and uplands, CSS agreement land contained a greater proportion of grassland, but with a reduced proportion of important upland Broad Habitats, such as Dwarf Shrub Heath and Bog, although these do tend to be found more in the Environmentally Sensitive Areas. The differences between the CSS and the countryside as a whole clearly reflect the priorities of the CSS, especially the high proportion of grassland. The CSS has targeted Broad and Priority Habitats and in this respect has been successful.

Landscape modelling using integrated airborne multi-spectral and laser scanning data

By integrating multi-spectral and elevation data from airborne sensors (CASI and ALTM) and adopting a parcel-based approach, a progression is achieved from land-cover classification to landscape modelling. This work involved data integration, per-parcel classification, knowledge-based correction and the derivation of landscape objects. For a 1 km 2 study area, a 14 land-cover class vector dataset was generated in which the parcels relate to landscape objects and contain information on their structure and 'terrain' context. At a 1 m spatial resolution, the correspondence between land-cover mapped using the airborne sensor data and identified by Countryside Survey 2000 field surveyors was 88%.