Effects of recreation and environment upon the erosion of mountain footpaths in the Lake District National Park.

Abstract

Increasing numbers of walkers in mountain areas have led to concern about the deterioration of footpaths through the erosion of vegetation and soil. Sites were established to monitor path erosion by repeated measurements of cross sections. Results demonstrated that although many sites were stable over a two year period, some deteriorated rapidly. Erosion by human agency and surface water run off proved equally effective under favourable conditions. Comparisons of air photographs (1947-72) suggested that footpath erosion was not a new phenomenon, but also reinforced the trends measured over the two years. A survey was made to examine relationships between footpath morphology and environmental/recreation site conditions. Results suggested that in the variation of path width, of the extent of bare soil and the depth of gullying, much could be accounted for by corresponding variation in the path gradient and the degree of recreation pressure. The altitude, and certain vegetation and soil types proved relevant, but of less importance. Among the paths surveyed, the extremes of erosion measured were localised, but occurred on most paths. Signs of active processes were observed on about one third of the sites, and appeared on most paths with a slope of more than 17 degrees. Experimental work on a purposely created path demonstrated the efficacy of trampling as an erosive agent, especially in combination with wet weather and waterlogged soil.