Issue 3 ENVIRONMENT MINISTER ASKS WHAT IS HAPPENING TO OUR COUNTRYSIDE? CONTENTS IS IT REALLY CLEVER? MEASURING VEGETATION CHANGE

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1 JUNE 99 Issue 3 NEWSLETTER FOR THE COUNTRYSIDE SURVEY 2000 ENVIRONMENT MINISTER ASKS WHAT IS HAPPENING TO OUR COUNTRYSIDE? Following publication of the results of the 1990 Countryside Survey a series of follow up studies were undertaken, known as the ECOFACT programme. This research sought to develop new approaches to analysing vegetation and to identify the causes of changes observed following the 1990 survey. Environment Minister Alan Meale, (speaking in March at the SET 99 exhibition in Bristol) announced the launch of the first of these publications. Vegetation of the British Countryside as the report is ambitiously titled, describes a new statistical classification called the Countryside Vegetation System (CVS) which encompasses the full range of common vegetation sampled throughout Great Britain. Mr Meale said: We need to know what is happening to our countryside and this scientific study will help us to improve our understanding of the changes which are taking place. The CVS provides a ready-made reference system for assessing the distribution, ecological associations and environmental determinants of common vegetation types. The classification procedure is strictly objective and reproducible, easy-to-use and freely available on the Internet. The second volume, (to be published in June) will show how British vegetation changed during the study period ( ). Using several different methods it was confirmed that there were significant declines in the diversity of plants in Britain in a range of habitats. The most marked declines were in the botanical diversity of unimproved and semi-improved agricultural grasslands. Plants that changed in abundance included food plants associated with declining butterflies and seed-eating birds of lowland farmland. The overall changes in vegetation indicate trends towards the increased abundance of common plant species associated with greater levels of nutrient availability. Inside this issue CS2000 News asks how the CVS will be used in the analysis of CS2000 data as well as details of how to obtain copies of the ECOFACT publications. CONTENTS IS IT REALLY CLEVER? USING ECN TO INTERPRET CS2000 VEGETATION RESULTS THE NORTHERN IRELAND COUNTRYSIDE SURVEY MEASURING VEGETATION CHANGE Environment Minister, Alan Meale, and school children at the SET 99 exhibition A BETTER QUALITY OF LIFE

2 IS IT REALLY CLE How will new approaches to satellite mapping benefit the user? The Land Cover Map of Great Britain (LCMGB) has been one of the most widely used of Countryside Survey 1990 datasets with some 300 licenced users to date. For the Land Cover Map 2000 (LCM2000), newly developed techniques known collectively as CLEVER-Mapping are being used both to improve the accuracy of land cover mapping and to produce a more flexible product which can be integrated with data from other sources. In this article, CS2000 News has asked Geoff Smith to cut through the technical jargon and explain what CLEVER-Mapping is and why he thinks it will benefit the user. The source of data for LCM2000 is no different to that available in The same satellite still collects data on a regular grid (approximately 25 m) and we use two images, one from winter when deciduous vegetation has died back, and one from summer at the height of the growing season. The difference for LCM2000 is how we process these data. In 1990 we took each pixel separately and classified it as a single land cover type. One of the drawbacks to this approach was that pixels with a mixture of land cover were difficult to classify. The novelty of the CLEVER-Mapping approach is that we are dividing the landscape into land parcels and looking at groups of pixels as an entity. The easiest way to visualise what is going on is to think of field patterns in an agricultural landscape. The CLEVER-Mapping approach would look at a whole field and Example of output from the 1997 Land Cover Map of Jersey showing a range of stored data

3 VER? classify it according to the most likely land cover type, ignoring the confused signals from edge pixels, and smoothing any internal variation. The result is a map showing each land parcel, rather than each pixel, coloured up to represent land cover or Broad Habitat types. This was the approach used to produce the 1997 Land Cover Map of Jersey. The product was a state-of-the-art land cover database for the Island, with 21 land cover types and 9 arable sub-types. Validation estimated the accuracy to be 95 %. As well as recording the most likely land cover type, the system also stored a score for the probability with which the land parcel had been classified plus additional contextual information. In the Jersey example, digital cartography provided the linework used to divide up the landscape into field patterns or land parcels. In LCM2000, a similar approach is planned for Northern Ireland. But, for the rest Image segmentation techniques have been successfully applied in upland situations. This example shows a 1 km square in the Cairngorms of the UK, image segmentation is being used to create the linework. Segmentation looks for both discontinuities and uniform areas in the original satellite images, to divide up the landscape. This procedure has been shown to work well in the lowlands, discriminating the field patterns, and in the uplands where it has the advantage of dividing up tracts of open countryside objectively according to cover and spectral characteristics. The use of the per-parcel approach does not mean local information is lost, far from it. Gridded data, like those from 1990, will be added to the Geographical Information System (GIS) database, to record the within-field patterns as well as a field s dominant cover. Users of LCM2000 will have access to a much more flexible product, cross-referencing several types of information and offering the possibility to integrate yet more data into the system. Geoff Smith A leading member of the LCM2000 team, based at ITE Monks Wood

4 USING ECN TO INTERPRET CS2000 VEGETATION RESULTS Eight years have passed between the last Countryside Survey in 1990 and the CS2000 field survey. Major changes over that period can be detected but it is important to make sure that the picture is not clouded by any short-term factors which only applied during For example, the summer of 1998 was much wetter than the last few years in many parts of the country did this have an impact on the vegetation? If it did, do we need to make any allowance in our interpretation of the results? In order to deal with this sort of issue, CS2000 is using Environmental Change Network (ECN) sites to assess year to year changes in vegetation. ECN is a collaborative programme sponsored by the main environmental regulation authorities and research organisations in the UK. The aim is to intensively monitor a varied series of sites for a wide range of environmental variables, from physical ones such as climate and air pollution to biological ones, such as vegetation composition and animal populations. In this way it should be possible to not only detect changes, but also identify the likely causes of these changes. The different sites are run by different organisations but all use the same methods and regular checks are made to ensure consistency. There are in fact two networks, a terrestrial one and a freshwater one, but the main interest for CS2000 is the terrestrial network. At 10 of the terrestrial ECN sites, vegetation has been recorded annually in permanently marked plots in order to help interpret the main CS2000 vegetation survey. A major analysis of the data will be carried out after the survey at ECN sites has been repeated again this summer. The first step will to be to identify those plants and vegetation types which vary most year to year, we will then be able to test whether the patterns we find can be explained by changes in other aspects of the environment. One of our top priorities will be to look at the effects of weather. A preliminary look back over the last few years indicates that some vegetation changed after the unusually hot, dry summer we had in 1995: it will be interesting to see if these changes have been reversed! Michael Morecroft A member of the ITE Environmental Change Network group, based at Wytham Wood

5 THE NORTHERN IRELAND COUNTRYSIDE SURVEY A separate survey, using a similar approach to CS2000, has been carried out concurrently in Northern Ireland. The Northern Ireland survey is a repeat of a series of surveys carried out by the University of Ulster on behalf of the Environment and Heritage Service Northern Ireland between 1986 and The surveys originated as independent studies of Areas of Outstanding Natural Beauty for which the aim was to provide consistent environmental information on environmental resources as part of the re-designation process. The approach was subsequently extended to the Fermanagh District and the wider countryside in order to cover the whole of Northern Ireland and is seen by the Environment and Heritage Service as a key database for strategic planning and resource estimation. The Northern Ireland Countryside Survey and CS2000 are broadly similar in their approach, both adopting a sampling strategy based on a classification of the underlying environment. A strength of the Northern Ireland survey is that its sampling unit is smaller than that for CS2000, (25 ha rather than 1 km square) but the sampling intensity is much higher. This enables greater capability in making regional estimations. Vegetation plots were not recorded in the original Northern Ireland survey but have subsequently been added in 1993 and They differ from the CS2000 vegetation plots in being targeted at selected semi-natural vegetation types (grasslands, heaths and bogs). A separate project is being undertaken as part of the CS2000 programme by ITE on behalf of DETR to forge links between the surveys with the ultimate aim of joint UK report. This work is being carried out alongside the two surveys to recommend how field survey recording protocols can be related. The first report of this project concluded that integration could be achieved by adopting the Broad Habitats as a common reporting framework. This will provide for the first time, a consistent common reporting framework for biodiversity in the UK. To find out more about the Northern Ireland survey contact: Alan Cooper at the University of Ulster (a.cooper@ulst.ac.uk). SHORTS Land Cover Map is now UK Links between CS2000 and the Northern Ireland Countryside Survey were further strengthened in March when EHS, DANI, OSNI, DETR and NERC agreed to jointly fund a satellite Land Cover Map for Northern Ireland. The work will be carried out alongside the consortium funded Land Cover Map for Great Britain project and means that for the first time a complete UK map will be produced. CIS new version Version 6 of the Countryside Information System software is scheduled for release in June For more information about the new version contact: Sue Wallis, Fiona Pugh or Tim Moffat, at the Environmental Information Centre, ITE Monks Wood, Abbots Ripton, Huntingdon, Cambridgeshire, PE17 2LS, Tel: , Fax: , EIC@ITE.AC.UK or visit the Web site ( Completion of the CS2000 field work After the difficulties experienced due to the poor weather conditions in northern Britain last summer (see CS2000 News No 2), plans are now well advanced to complete the CS2000 field survey during Additional funding is being offered by DETR, NERC and the Scottish Office. The work programme has been adjusted so that the data from the 50 remaining squares will slot straight into the data analysis with no overall delay in the reporting schedule.

6 MEASURIN C An example of the distribution of vegetation plots within a 1 km sample square with surveyors recording a main field plot and a linear verge plot The Countryside Vegetation System (CVS) was referred to on the front page of this issue of CS2000 News. CVS and other analytical techniques developed under the ECOFACT programme, provide a novel toolkit for measuring changes in the botanical quality of the countryside and the processes involved. In this article CS2000 News asks Simon Smart of the vegetation analysis team how and why vegetation data have been collected in CS2000. How has vegetation data been collected in CS2000? The basic sampling unit for the CS2000 field survey is a 1 km square, and the vegetation data are collected from a series of plots within the square. A list of plant species and their abundance has been recorded from eleven types of plot, each designed to sample different landscape elements such as fields, field boundaries, road verges, streamsides, arable field Vegetation of the British Countryside is the first in a series of research reports commissioned by DETR which examine the ecological factors causing changes in the British vegetation. The work was undertaken by the Institute of Terrestrial Ecology, a component research organisation of the Natural Environment Research Council (NERC). The 224 page manual is illustrated in full colour with photographs, maps and diagrams. It is available from the DETR publication sales unit, priced 48, ISBN Department of the Environment, Transport and the Regions Publications Sale Centre Unit 21, Goldthorpe Industrial Estate Goldthorpe Rotherham S63 9BL Tel: Fax: The CVS structure is available as a software package which enables a user to classify sample plots. The package is currently available via the Internet: Volumes 2 and 3 are currently in press and will be available from: ITE Publication Sales, Monks Wood, Abbots Ripton, Huntingdon, Cambs PE17 2LS. Tel: Fax:

7 G VEGETATION HANGE margins and open countryside. The random sampling approach tends to favour representation of the typical rather than the specialised vegetation communities. The number of plots recorded depends on which landscape elements are present in the 1 km square, the average is 30 plots per square. The plots are permanently marked and georeferenced using GPS so that the exact locations can be re-located and re-surveyed in subsequent years. In 1978 around 2,500 plots were surveyed. This increased to around 11,500 plots in 1990 and 15,714 in 1998 (and further plots will be surveyed in 1999). The botanical data from the series of Countryside Surveys are recorded to consistent and rigorous standards. They constitute a unique national data set for quantitative vegetation analysis of Broad Habitat types. Why collect vegetation data? Vegetation data are particularly valuable because plants are not only the essential components of terrestrial ecosystems, including those important for agriculture or forestry use and nature conservation, but also because the plant species themselves carry The relationships between CVS classes may be interpreted in terms of environmental gradients information about the changing environmental conditions in which they grow. In practical terms, plant assemblages are mostly immobile and change relatively slowly they are, compared to other organisms, straightforward and feasible to survey on a national, synoptic basis. What is the Countryside Vegetation System? The first stage in creating the CVS was to group all of the vegetation plots collected in 1978 and 1990 into 100 vegetation classes. The newly formed classes were further grouped into eight aggregate classes. The relationship between these aggregate classes and their constituent vegetation classes is represented in the diagram. Further examination of this diagram revealed that it could be interpreted in terms of environmental gradients. Thus, movement from left to right could be allied with decreasing levels of soil nutrients, whilst moving from bottom to top was associated with more shade and less disturbance. Further, it is possible to visualise changes in land management as movement within the diagram. For example heathland and moorland vegetation is usually maintained by management (disturbance), and, where management is relaxed, succession typically occurs, with the vegetation moving diagonally higher and to the left, towards woodland. Simon Smart A member of the Land Use research group, at ITE Merlewood

8 A BETTER QUALITY OF LIFE The Deputy Prime Minister, John Prescott launched the Government s long awaited Sustainable Development Strategy on 17 May, and placed emphasis on new ways of assessing how well we are doing. The White Paper confirms that the special natural, cultural and archaeological characteristics of our landscape are highly valued and must be retained, and that we must reverse the decline in wildlife and habitats. But, at the same time, we should not be aiming for a landscape frozen in time much of our valued landscapes and habitats are a product of centuries of human activity and gradual change in the countryside. Some change is inevitable, allowing for activities such as local enterprise, agriculture, forestry and renewable energy production, or to meet housing needs. But change must be well-managed. Countryside Survey 2000 will show how the British countryside has changed over the past ten years and will be used to assess whether policies for a sustainable countryside are working. For example, the Government will use the results of CS2000 to help decide whether the legislative protection now afforded to hedgerows should be extended to other field boundaries. Two of the core indicators of sustainable development landscape features and trends in plant diversity which are due to be published later in the year, will be updated with data from CS2000. A better quality of life: A strategy for sustainable development for the United Kingdom, Cm 4345 (May 1999) is available from The Stationery Office, or visit the web site: sustainable/quality/life. YOUR VIEWS WOULD BE WELCOMED Publication of the first results of CS2000 is scheduled for November Several more issues of CS2000 News are planned in the meantime and we would like to ensure that as well as providing updates on progress CS2000 News features articles that explain why the survey is being undertaken and what can be expected of the results. We would welcome reader s suggestions for topics to feature in future issues of CS2000 News. If you have any comments about the newsletter, or would like us to amend our circulation database then please contact Diane Whittaker at the address given at the foot of this page. Current and previous issues of this newsletter are accessible via the Internet. STEERING THE SURVEY The Department of the Environment, Transport and the Regions has established an Advisory Group to provide advice on the requirements for CS2000, including the content of the survey, coordination with other work and presentation of the results. At the last meeting of the Advisory Group in March a specification for the analysis of CS2000 field survey data using BAP Broad Habitats was approved. The next meeting of the group will be in September and will, amongst other things, consider proposals for a summary report for the whole CS2000 programme scheduled to be published in November Organisations represented on the Advisory Group for CS2000 are: Department of the Environment, Transport and the Regions Forestry Commission Ministry of Agriculture, Fisheries and Food Scottish Office Welsh Office Countryside Agency Countryside Council for Wales English Heritage English Nature Environment Agency Environment and Heritage Service Northern Ireland Farming & Rural Conservation Agency Countryside Survey 2000 is sponsored by: Department of the Environment, Transport and the Regions, Natural Environment Research Council, Ministry of Agriculture, Fisheries and Food, Welsh Office, Scottish Office, Environment Agency, Scottish Natural Heritage, and Countryside Council for Wales. Countryside Survey 2000 News has been collated and produced by the Institute of Terrestrial Ecology on behalf of the DETR and NERC. Joint Nature Conservation Committee Scottish Environment Protection Agency Council for the Protection of Rural England National Trust Royal Society for the Protection of Birds Wildlife and Countryside Link Institute of Freshwater Ecology Institute of Terrestrial Ecology University of Nottingham University of Sheffield. Contact address: CS2000 Institute of Terrestrial Ecology Merlewood Research Station Grange over Sands Cumbria LA11 6JU Tel: Fax: CS2000@ITE.AC.UK