Accounting for Nature: Assessing habitats in the UK countryside
2.   The National Picture

Conclusions

2.39 In this chapter, some of the key national trends that emerge from the analyses of CS2000 and NICS2000 information have been presented. Some of the changes we have seen in Great Britain between 1990 and 1998 differ markedly from those observed prior to 1990.

2.40 In England and Wales, the area of the Broadleaved Woodland and Built-up Broad Habitats both increased by 4% and 5%, respectively, reflecting policies for woodland planting and the impact of urban growth. Less expected was the 17% decline in the semi-natural Acid Grassland Broad Habitat. In Scotland, Broadleaved Woodland showed an even bigger increase of 9%, along with a 19% increase in the semi-natural Fen, Marsh and Swamp Broad Habitat. For Great Britain as a whole there was an 18% loss of Calcareous Grassland, a habitat of conservation importance.

2.41 In Northern Ireland there have been decreases of the Arable and Horticultural and Calcareous Grassland, and gains in Broadleaved Woodland Broad Habitats. Improved Grassland has increased largely by the more intensive agricultural use of formerly Neutral Grassland. Given the high conservation status of some hay meadows included in Neutral Grassland, the process of decline deserves investigation.

2.42 One of the most significant results of CS2000 concerns landscape features, such as hedges, walls and lowland ponds, used in the Government’s Quality of Life Counts indicator. Overall, the indicator for landscape features shows that in Great Britain the decline in length of hedges and walls reported for the 1980s has been halted. In the case of hedges in England and Wales, there is some evidence that losses in the early 1990s have been reversed. Lowland ponds show a small net increase. However, in Northern Ireland the stock of hedges and earth banks declined.

2.43 The overall analysis of vegetation condition in Great Britain shows very marked trends towards increasing levels of nutrient availability – or eutrophication – and conditions, which favour tall, competitive plants especially on linear features. These trends were evident in the majority of vegetation types and especially in the semi-natural vegetation types important for biodiversity – infertile grassland, upland wooded, moorland grass and heath and bog vegetation. A different trend towards lower nutrient levels and more competitive plants was shown in the vegetation of crops and weeds, perhaps showing the effects of set-aside and arable-ley rotations.

2.44 The Government’s Quality of Life Counts indicator for plant diversity shows that changes in plant diversity have reduced in magnitude since the 1980s, but during the 1990s losses have been mostly associated with the vegetation found in managed agricultural grasslands, field boundaries and verges. Perhaps of greatest concern is the continuing decline in plant diversity in infertile grassland – the vegetation typical of wildflower meadows and species-rich banks and verges. A more detailed analysis of these changes is presented for each of the Broad Habitats in the Chapters that follow.