Geostatistical and multivariate analysis of the horizontal distribution of an earthworm community in El Molar (Madrid, Spain)

摘要

The eartnworm community in El Molar (Madrid) is studied, and its distribution, patterns ancj reiatjOn vvith some soil factors are described by using geostatistic and onzon a multivariate tools. Six species were found, Hormogaster elisae, Allolobophora rosea, anc| A{{oiQbQphora caliginosa being the three most abundant ones. These species exhibited a clumped distribution. The most dominant species, H. elisae, was distributed in patches of an average size of 45 m in spring and more than 100 m in autumn. A. rosea was aggregated in patches of an average size of 22 m and A. calisinosa 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. ? 2007 Elsevier GmbH. All rights reserved.