Accounting for Nature: Assessing habitats in the UK countryside
3.   Enclosed Farmland - Arable and Horticultural, Improved and Neutral Grasslands

Conclusions and implications

3.41 The changes between Broad Habitats and assessment of vegetation condition provide complementary information about changes in enclosed farmland habitats. The overall extent of the Arable and Improved Grassland Broad Habitats, which are the most extensive habitats in the UK, changed little between 1990 and 1998. Small proportions were converted to woodland or developed land. There was some evidence for increasing plant diversity in the Arable Broad Habitat, especially in the margins of the fields. These changes may reflect rotations between crops and sown leys, as well as managed set-aside and creation of uncultivated headlands and field corners. In Improved Grassland, plant diversity tended to decline and nutrient levels increased.

3.42 Neutral Grassland, which includes some species-rich hay meadows as well as areas of unmanaged grassland, represents only 7% of the area of enclosed farmland. These grasslands showed large fluxes with losses in Scotland and Northern Ireland but gains in England and Wales. Overall 13% of Neutral Grassland was converted to the Arable, Broadleaved or Built-up Broad Habitats. The floristic character altered with increases in tall, competitive plants at the expense of more typical meadow plants.

3.43 Given the continuing high intensity and specialisation of agricultural production in the UK countryside, it is perhaps not surprising that enclosed farmland habitats, particularly grasslands, have continued to decline in diversity and value as wildlife habitats. The analysis suggests that whilst little change may have taken place on already highly intensive agricultural land there has been a steady loss of the surviving parcels of less improved grasslands, especially in Scotland and Northern Ireland. These changes are synchronous with the declining frequency of typical meadow flowers and grasses and increasing levels of fertility in England and Wales. The botanical trends deserve more detailed analysis to determine their significance for other species groups, such as farmland birds, for which BAP targets have been set, and to assess the causes of the changes.

3.44 Results of CS2000 and NICS2000 for the general countryside cannot provide direct evidence about the effects of particular targeted agri-environment schemes. However, as Figure 3.10 shows, grasslands that are covered by the Countryside Stewardship Scheme in England are of better ‘average quality’ than those found in the wider countryside. Thus these policy measures do appear to have been directed towards conserving the more important elements of our ecological capital.

Figure 3.10: Frequency of different vegetation types in areas covered by the Countryside Stewardship Scheme (CSS) compared with land across England as surveyed by CS2000.

[Click on the graph to reveal the underlying data]

The CSS plots were sampled at random in 1998. CS2000 frequencies are from all main (x) plots in England in 1998.

3.45 Nor can the results be used directly to assess progress towards BAP targets for Priority Habitats. The Grazing Marsh and Hay Meadow Priority Habitats are localised in occurrence and are not well represented in the sample surveys. However, new plots established in 1998 in arable fields will provide a baseline for assessing future changes in the Cereal Field Margins Priority Habitat.

3.46 The extent to which agri-environment schemes are adequate, in terms of maintaining and improving the overall quality of the farmed landscape, cannot be determined here. Such issues will be an important focus for future research and more detailed analysis of CS2000 and NICS2000 data. The value of the Countryside Surveys is that they provide an unbiased view of large-scale vegetation change that can be used to evaluate local trends.