Individual study: Changes in two high altitude blanket bogs after the cessation of sheep grazing
Rawes M. (1983) Changes in two high altitude blanket bogs after the cessation of sheep grazing. Journal of Ecology, 71, 219-235
This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.
Exclude or remove livestock from degraded peatlands
A replicated, paired, controlled, before-and-after study in 1966–1980 in two grazed blanket bogs in England, UK (Rawes 1983) found that excluding sheep increased shrub cover, but typically had no effect on cover of moss or herb species. In exclusion plots, cover increased of heather Calluna vulgaris (before: 0–4%; after 14 years: 2–21%) and crowberry Empetrum nigrum (before: 7–17%; after: 27–42%). These changes were significant in two of four comparisons, with a similar trend in the others. Cover of two other shrub species did not decline. There was no significant change in cover of six of six moss species, including two Sphagnum (before: 0–10%; after: 1–21%) or in 8 of 11 comparisons involving herb species, including black sedge Carex nigra (before: 6%; after: 4%) and cottongrasses Eriophorum spp. (before: 18–72%; after: 16–69%). Vegetation cover generally did not change in grazed control plots (except for a decrease in heather cover in one site, from 6% to 3%). In 1966, 0.1 ha of each bog was fenced to exclude sheep. An adjacent plot in each bog, with similar vegetation, was left open to grazing (<0.5 sheep/ha). In 1966 and 1980, vegetation cover was measured using 500 systematically placed pins in each plot.
(Summarised by Nigel Taylor)