Abstract:

This study aimed to analyze the differences of soil collembola community characteristics under different vegetation reclamation treatments in the moderate degraded grasslands in the Songnen Plain of Northeast China.

Based on the data of soil collembola collected in the Songnen grasslands of different treatments from May to October in 2005, the community parameters such as group number, individual density, and diversity index were calculated. The results showed that a total of 1 156 soil collembola individuals were captured, which fell into 9 families and 19 genera. In contrast to over grazing, both fencing enclosure and planting alfalfa could improve soil properties and substantially increase group number, individual density, and diversity of soil collembola in the moderate degraded grasslands. This suggests that fencing enclosure and planting alfalfa were helpful to restore the soil environment and ameliorate collembol a community. However, the individual density of collembolans in planting alfalfa treatment was significantly higher than that of fence enclosure treatment. Further information came from the comparison of collembola taxa that Isotomidae, E ntomobryidae and Sminthuridae were significantly restored after reclamation. Comparing collembola taxa in fencing enclosure vs. plantin g alfalfa treatments, we found that fencing enclosure maybe more favorably restored Entomobryidae and Sminthuridae, and planting alfalfa perhaps more successfully reclaimed Isotomidae. At sites of the fencing enclosure treatment, the individual density of Entomobryidae reached a level of 5.14 times that of over grazing treatment, and the individual density of Sminthuridae reached 2.38 times that of over grazing treatment. At sites of the planting alfalfa treatment, the individual density of Isotomidae reached 3.33 times of over grazing treatment.

Key words: Soil collembola, community characteristics, degraded grasslands, vegetation reclamation, fencing enclosure, planting alfalfa, Songnen grasslands.24 Refs. In Chinese