Community structure of soil macrofauna under different land-use systems in the purple hilly areas of Sichuan Basin

In winter 2006 and spring 2007, soil macrofauna were investigated in four land-use systems (field margin, farmland, orchard and forestland returned from farmlands) in the purple hilly areas of Sichuan Basin. The soil macrofauna were manually sorted. A total of 2 838 soil individual macrofauna were captured and classified into 3 phyla and 9 classes. Results of the study show that individual density, group number and DG diversity index of soil macrofauna communities significantly vary with land-use systems. Individual density is significantly higher in field margins than in other forms of land-use, especially in the winter season, group number and DG diversity index are significantly higher in field margins than in farmlands and returned forests. The lowest individual density, group number and DG diversity index exists in farmlands. Individual density and group number decrease with increasing soil depth in the four land-use systems. Jaccard and Grower coefficients have a high similarity among soil macrofauna communities in field margin, orchard and returned forestland. A low similarity is observed among soil macrofauna communities in farmland and field margin, farmland and orchard, farmland and returned forest. The findings suggest that soil macrofauna communities are strongly influenced by land utilization. Also, field margin plays an important role in conserving soil macrofauna.