D.C. Howard

Objectives and applications of a statistical environmental stratification of Europe

Stratifications are made to divide environmental gradients into convenient units and then to use these as areas in which objects and variables might have relatively consistent characteristics. Statistical classification is a useful approach for obtaining this insight into complex environmental patterns and help to simplify heterogeneity. Traditional classifications of the environment are mostly subjective and based on expert knowledge. They are largely intended for descriptive purposes. Present day techniques now allow for continent wide statistically based environmental stratifications that can be applied consistently throughout Europe. Such environmental stratifications can provide the basis for assessment and monitoring biodiversity, land cover and land use and be a starting point for reporting on the European environment. The stratification presented here allows upscaling and downscaling, if needed to reach specified objectives. It can be applied in environmental reporting. Its application as a framework for land cover estimation is elaborated using Portuguese Land cover data.

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.

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.

Sources of variability in greenhouse gas and energy balances for biofuel production: a systematic review

Across the energy sector, alternatives to fossil fuels are being developed, in response to the dual drivers of climate change and energy security. For transport, biofuels have the greatest potential to replace fossil fuels in the short‐to medium term. However, the ecological benefits of biofuels and the role that their deployment can play in mitigating climate change are being called into question. Life Cycle Assessment (LCA) is a widely used approach that enables the energy and greenhouse gas (GHG) balance of biofuel production to be calculated. Concerns have nevertheless been raised that published data show widely varying and sometimes contradictory results. This review describes a systematic review of GHG emissions and energy balance data from 44 LCA studies of first‐ and second‐generation biofuels. The information collated was used to identify the dominant sources of GHG emissions and energy requirements in biofuel production and the key sources of variability in published LCA data. Our analysis revealed three distinct sources of variation: (1) ‘real’ variability in parameters e.g. cultivation; (2) ‘methodological’ variability due to the implementation of the LCA method; and (3) ‘uncertainty’ due to parameters rarely included and poorly quantified. There is global interest in developing a sustainability assessment protocol for biofuels. Confidence in the results of such an assessment can only be assured if these areas of uncertainty and variability are addressed. A more defined methodology is necessary in order to allow effective and accurate comparison of results. It is also essential that areas of uncertainty such as impacts on soil carbon stocks and fluxes are included in LCA assessments, and that further research is conducted to enable a robust calculation of impacts under different land‐use change scenarios. Without the inclusion of these parameters, we cannot be certain that biofuels are really delivering GHG savings compared with fossil fuels.

MIRABEL: Models for Integrated Review and Assessment of Biodiversity in European Landscapes

Abstract In this paper, we present the methodology and some results from the application of an integrating conceptual framework, MIRABEL, to analyze the consequences of environmental change for biodiversity. For 28 European countries, MIRABEL tabulates changes in the status of threatened habitats predicted to result from 10 environmental pressures. Regional variations in the severity of the pressures and impacts are taken into account by compiling separate impact tables for each of 13 Ecological Regions. Results suggest that agricultural intensification is one of the main threats, however, differences recorded by MIRABEL in the intensity of the pressures, their rate of change and their past and expected impacts on biodiversity in the various Ecological Regions is telling evidence of Europes biogeographical variety, and of the need to take this into consideration when assessing environmental change.

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.

The ITE Land classification: Providing an environmental stratification of Great Britain.

The surface of Great Britain (GB) varies continuously in land cover from one area to another. The objective of any environmentally based land classification is to produce classes that match the patterns that are present by helping to define clear boundaries. The more appropriate the analysis and data used, the better the classes will fit the natural patterns. The observation of inter-correlations between ecological factors is the basis for interpreting ecological patterns in the field, and the Institute of Terrestrial Ecology (ITE) Land Classification formalises such subjective ideas. The data inevitably comprise a large number of factors in order to describe the environment adequately. Single factors, such as altitude, would only be useful on a national basis if they were the only dominant causative agent of ecological variation.The ITE Land Classification has defined 32 environmental categories called ‘land classes’, initially based on a sample of 1-km squares in Great Britain but subsequently extended to all 240 000 1-km squares. The original classification was produced using multivariate analysis of 75 environmental variables. The extension to all squares in GB was performed using a combination of logistic discrimination and discriminant functions. The classes have provided a stratification for successive ecological surveys, the results of which have characterised the classes in terms of botanical, zoological and landscape features.The classification has also been applied to integrate diverse datasets including satellite imagery, soils and socio-economic information. A variety of models have used the structure of the classification, for example to show potential land use change under different economic conditions. The principal data sets relevant for planning purposes have been incorporated into a user-friendly computer package, called the ‘Countryside Information System’.

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

Abstract 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.

Estimating the extent and change in Broad Habitats in Great Britain.

A stratified random sample of kilometre squares in Great Britain was visited and completely mapped using four areal themes (agriculture and semi-natural vegetation, forestry, physiography and buildings and communications). The maps were digitised and the attribute information recorded to produce an electronic database. Information was summarised by square and then bootstrap re-sampling techniques were used to produce national estimates with statistical confidence intervals. The results for 1998 showed the terrestrial Broad Habitats had a range in extent covering two orders of magnitude from Montane (49000ha) to Improved Grassland (5482000ha). Just under half of Britain is covered by agricultural Broad Habitats, about 12% by woodland and just under 10% by Urban Habitats. The remaining quarter of the land area is covered by semi-natural Broad Habitats. By revisiting the same sample of squares previously visited in 1990, changes in the quantity and quality of the Broad Habitats have been determined. Significant increases in area have occurred in the Broadleaved, Mixed and Yew Woodland and Built Up and Gardens. The largest areal reduction was in Acid Grassland although that was in part balanced by a gain in Fen, Marsh and Swamp. The most significant ecological loss was in the area of Calcareous Grassland. The consequences of having different sample sizes for the different years are discussed.

Observations of Fukushima fallout in Great Britain

Following the Fukushima accident in March 2011, grass samples were collected from 42 sites around Great Britain during April 2011. Iodine-131 was measurable in grass samples across the country with activity concentrations ranging from 10 to 55 Bq kg(-1) dry matter. Concentrations were similar to those reported in other European countries. Rainwater and some foodstuffs were also analysed from a limited number of sites. Of these, (131)I was only detectable in sheeps milk (c. 2 Bq kg(-1)). Caesium-134, which can be attributed to releases from the Fukushima reactors, was detectable in six of the grass samples (4-8 Bq kg(-1) dry matter); (137)Cs was detected in a larger number of grass samples although previous release sources (atmospheric weapons test and the 1986 Chernobyl and 1957 Windscale accidents) are likely to have contributed to this.