Downland - Downland Habitat

Downland Habitat

In temperate regions chalk downland is typically calcareous grassland, a habitat formed by grazing from both livestock and wild animals. Chalk downland is often unsuitable for intensive agriculture, horticulture or development, because of the nutrient-poor, shallow soil and difficult slopes. For this reason downland often survived uncultivated when other, more easily worked land was ploughed or reseeded. However, equally this shallow soil structure makes downland ecosystems extremely fragile and easy to destroy. With modern machinery and fertilizing techniques it has become possible to use some previously uncultivated downland for arable farming, and the decline of extensive grazing has meant that many areas of downland, whilst not cultivated, when ungrazed revert to scrub or other less rare habitat, essentially destroying the delicate calcareous grassland. The UK cover of lowland calcareous grassland has suffered a sharp decline in extent since the middle of the 20th century. There are no comprehensive figures, but a sample of chalk sites in England surveyed in 1966 and 1980 showed a 20% loss in that period and an assessment of chalk grassland in Dorset found that over 50% had been lost between the mid-1950s and the early 1990s. Much remaining chalk downland has been protected against future development, due to its unique biodiversity.