Study On The Changes Of The Soil Animal Community Features Under The Condition Of Different Water-Soil Erosion Controlling Methods In Huangfu-chuan Watershed

The sampling plots for this study located in Wufendigou and Yangquangou ravine, Huangfu-chuan watershed in Inner Mongolia. Five kinds of different water-soil erosion controlling measures, i.e., pine woodland,aspen woodland,artificial shrub,artificial-planded weadow and abandoned cropland were chosen for sampling sites. And using farmland,grassland and degenerated grassland as control sites. The composition of soil animal communities, diversity, seasonal dynamics, variation characteristics of the niche, the correlation between of soil animal communities and environmental factors were analysed. The main results as follows.1. In this study, a total of 2088 soil macrofauna belonging to 1 phyla, 3 classes, 8 orders and 35 families were colleted. The dominant groups were Melolothidae larvae and Formicoidae imago. There individual number account for 73.71 percent of the total individual numbers of soil macrofauna. The common groups were Gnaphosidae, Carabidae larvae, Staphylinidae imago, Melolothidae imago, Elateridae larvae, Curculionidae larvae, Asilidae larvae and Carabidae larvae. A total of 14747 meso- and microfauna belonging to 5 phylas, 7 classes and 7 orders were collected. The dominant group was nematode. Tts individual number account for 95.53 percent of the total individual numbers of meso- and microfauna. In addition, the common groups consisted of Acarina and Collembola, respectively account for the total 2.14% and 1.51 %, other groups were account for the total 0.82%.2. Compared to control, the individual number of soil macrofauna in different water-soil erosion controlling methods has increased significantly, and the aspen woodland increased most remarkable, While the group numbers of soil macrofauna is significantly lower than control sites. In addition, the dominant groups of soil macrofauna communities has less change, however, the change of community composion has reflected in the common and rare groups. The individual number of meso-microfauna in different Water-Soil Erosion controlling methods has increased significantly, and the artificial-planded weadow increased most remarkable, While the group numbers of meso-microfauna has no obvious change. the dominant groups of meso-microfauna communities has less change, however, the change of community composion has reflected in the common groups. The common groups has increased significantly than control sites.3. The different water-soil erosion controlling methods does not haveobvious influence to the vertical distribution of soil animal. The individual numbers and group numbers of soil macrofauna in study area showed significantly surface accumulate in the vertical distribution. Specially, the farmland displayed opposite result to above. The vertical distribution of meso-microfauna respectively different.4. The dominant groups and common groups have a larger niche breadth. Specially, the dominant Melolothidae larva has narrow niche breadth. The Melolothidae imago and Melolothidae larva in nine major groups of soil macrofauna have large niche overlap, as well as it has a wide niche breadth between the Asilidae larvae respectively and Melolothidae imago,Melolothidae larva,Elateridae larvae,Curculionidae larvae, these groups is similar to the use of resources, the differences of survival in habitat are not obviously.5. Compared to control, diversity index, simpson index, richness index and evenness index indicated that the diversity of soil macrofauna is lower in different water-soil erosion controlling methods. but the diversity of soil macrofauna in grassland is lower than the controlling region. The change trend of density-group is consistent with complexity index. It displayed result in agreement with above four kinds indexes, the diversity of soil macrofauna in controlling region is lower than control, but the farmland is specially, it's diversity is the lowest.6. The analysis of the correlation between density of soil animals and soil environmental essential factors showed that the individuals of soil macrofauna and soil meso-microfauna was restricted by soil conditions. It does not have obviously correlation between the individuals of soil macrofauna and soil conditions, however,It has correlation between the density of soil meso-microfauna and soil organic matter,soil total nitrogen,soil total phosphorus and soil available potassium.To sum up, Carrying out comprehensive management of water and soil in Wufendigou of Huangfu-chuan watershed. It plays a positive role on controlling soil erosion and improving ecological environment. Study on the changes of the soil animal community features in this area, It reflects that the diversity of some sample plots is lower, and it has single dominant groups. Therefore, it easy to cause insect outbreaking.