Soil invertebrates as bio-indicators in a natural area converted from agricultural use. The case study of Vallevecchia-Lugugnana in North-Eastern Italy.

This work aims to develop a sampling methodology, based on soil invertebrates, to provide a reliable and easy-to-perform measure of environmental quality. Hand-sorting and pitfall-trapping were the main sampling systems adopted because they are quick and easy to use and do not require particular skills or tools. Both agroecosystems (organic and conventional) and seminatural environments (planted woods, hedgerows, flooded areas) have been monitored in a coastal lagoon area reclaimed to farmland in North Eastern Italy. Taxa at high hierarchical levels proved to be useful in separating different type of habitat, but were unable to provide information about the type of rural management. Carabidae (Coleoptera) seem particularly useful in studying agroecosystems: 23 species have been collected, mainly in the organic farm and in the hedgerow. The earthworm population was mainly affected by type of soil. In agroecosystems, cultivated fields had fewer individuals with respect to hedgerow, probably due to disturbance caused by soil management practices.