The British uplands are a multifunctional asset that have several important functions with regard to climate change (as a major carbon source/sink), water quality and quantity, biodiversity, and primary production. Traditionally, the uplands have been regarded as an important source of high quality, inexpensive water, meeting over a third of the supply requirements in England and Wales, and providing ‘clean’ dilution water for more polluted, downstream water courses. Agriculture is a major contributor to water pollution, particularly nitrogen (N) and phosphorus (P), and it is commonly assumed that the low intensity of agriculture (and human populations) in the uplands means that these activities have a negligible impact on upland water quality (with the possible exception of sheep dips). However, it is the concentration rather than the chemical that causes pollution, and even in the absence of agriculture, naturally-occurring chemicals, such as N and P, can leach to water courses which will contribute to the total loadings further downstream against which water quality standards will be compared. Similarly, although agricultural activities in Less Favoured Areas (LFAs) may be more extensive than in lowland areas, it is not possible for these activities to have zero impact on water quality, but what is unclear, is the extent to which farming in LFAs contributes to water pollution.
The dominant agricultural activity in upland areas is the grazing of sheep and, to a lesser extent, cattle. Upland grassland areas cover a range of habitats including calcareous grassland, improved grassland, semi-natural rough grassland and areas of intensive in-bye grassland. Improved and intensive grassland have historically been managed to maximise the nutritional benefits of the vegetation and as such have a low diversity of both flora and fauna (e.g. Woodhouse et al., 2005). The importance of diversity within the environment is now recognised by policy makers in the form of Biodiversity and Habitat Action Plans, and PSA agreements on farmland birds and condition of SSSIs. Consequently, initiatives have been introduced to maintain and/or enhance biodiversity in upland grasslands (e,g. Environmental Stewardship (ES) schemes; Limestone Country Project) through, for example, the encouragement of mixed grazing and different breeds of livestock which, through different patterns of grazing and trampling, can enhance the floristic diversity, and also provide a more diverse sward structure, thus providing habitat conditions suitable for a more diverse range of wildlife. However, these changes in land management could conflict with other policy requirements such as those laid out in the Water Framework Directive, by introducing practices that are more detrimental to water (and soil) quality, although the majority of ES options should reduce water pollution (Ramwell et al., 2007). Moreover, it has been shown that CAP reform is likely to stimulate substantial change in upland land use, with extensification of agriculture, or even abandonment of agricultural production, likely over considerable areas, coupled with possible intensification and increases in grazing pressure in some of the more productive ‘in-bye’ areas (Parry et al., 2006).