Horizontal Distribution of an Earthworm Community at El Molar, Madrid (Spain)

Abstract

The earthworm community in El Molar (Madrid) is studied, and its distribution patterns and relation with some soil factors are described by using geostatistic and multivariate tools. Six species were found, Hormogaster elisae, Allolobophora rosea and Allolobophora caliginosa being the three most abundant ones. These speciesexhibited a clumped distribution. The most dominant species, H. elisae, was distributed in patches of an average size of 45m in spring and more than 100m inautumn. A. rosea was aggregated in patches of an average size of 22m and A. caliginosa formed patches of an average size of 38 m. There seemed to be a positive correlation between the abundance of H. elisae and the percentage of total and coarse sands, as well as a negative correlation with clay, nitrogen, carbon and coarse loams contents, opposite to what was observed for A. rosea.