Summit-type blanket mire erosion in the Forest of Bowland, Lancashire, UK: Predisposing factors and implications for conservation

Abstract

The incidence of summit-type mire erosion has been investigated in a mire complex in the Forest of Bowland, Lancashire, using a combination of palaeoecological and radiometric techniques in conjunction with documentary evidence. Macrofossil analyses suggest that Sphagna have been a dominant component of the vegetation on Fairsnape Fell over the last 2000 years. However, over the last 100 years, Sphagnum species have disappeared from many areas. We conclude here that this decline was caused by the onset of summit-type erosion, which in turn was initiated through a combination of unusual factors: a period of below-average rainfall in the region in the early 1900s, resulting in lowered water tables in the peat; exceptional summer drought in 1921; and a decline in management standards because of shortage of gamekeepers after the First World War. We believe that these precipitated a catastrophic burn (probably in 1921), which may well have been accidental in origin. High levels of atmospheric pollution did not cause the loss of Sphagnum, but may have influenced their ecology. The heather moorland and blanket mires of Bowland are internationally important habitats for many species of bird of prey, as well as being economically important for grouse shooting. Consequently, catastrophic fires that cause large-scale degradation of upland peat landscapes have important implications for the conservation of these ecosystems and of the scientific archive preserved in peat ecosystems. It is suggested that high sheep-stocking levels on Bowland may prevent recolonisation of bare peat surfaces, thereby allowing peat erosion to continue.