Influence of forest disturbance on earthworm (Oligochaeta) communities in the Western Ghats (South India)

In the Western Ghats (South India), the natural evergreen forest has been highly disturbed and fragmented for 150 years. The resultant vegetation is a mosaic of more or less disturbed forests, pastures, and crops (mainly paddy fields). This paper aims to assess the effects of anthropic disturbance on earthworm communities. Earthworms were collected at the end of the rainy season in a wide range of milieux distinguished by their vegetation, soil properties and topography. The earthworms found belong to the families Octochaetidae, Megascolecidae and Moniligastridae. Densities ranged from 35.3 to 545.3 ind m−2. Biomasses ranged from 2.35 to 52.56 g m−2. There was no clear relationship between these community characteristics and the vegetation, soil properties or topography as pastures and forests supported high or low densities (or biomasses). Nevertheless, some species were restricted to pastures, some species to forests and some species are found in all milieux.