Study On The Changes Of The Soil Animal Community Features Under The Management Of Grassland Restoration Of Cropland

The frangibility of ecological environment, inconsequence methods of cultivating, the time synchronization of blustery season and bareness of the land surface are the serious ecological problems in ecotonal grassland and cropland of north china. All these quicken up the process of wind erosion. Also quicken up the process of cropland desertification. It is a mainly process of the cropland degeneration in arid and semi-arid region of north china.Grassland and woodland restoration of cropland is a impactful approach for preventing the progress of cropland desertification and protecting the ecological environment. Since it is put in practice in our country, the greater economic and ecological profits are gained.In this paper, the studies of that the changes of the features of soil animal communities, biodiversities, vertical distribution, function groups, detritivorous scarab community under the condition of time prolonging and different managements of grassland restoration of cropland are conducted in Wuchuan region, Inner Mongolia. The main results as followed.1. During the 2005-2006 sampling period, a total of 55 groups and 1765 individuals of macro fauna have been collected. They belong to 4 classes, 11 orders, 47 families. Among them, the dominant group is Formicidae. And there are 13 common groups and 41 rarely groups. A total of 5 groups and 25590 individuals of meso- and microfauna have been collected. They belong to 8 classes, 6 orders, 5 families. The dominant groups are Namatoda and Enchytraeidae. The rarely group is Acarina. A total of 21337 individuals of detritivorous scarab have been collected. They belong to 4 families, 5 genuses, 20 species. The dominant species are Aphodius rectus Motschlsky and A. (Acrossus) sp.. Having 5 common species and 13 rarely species.2. After grassland restoraeion of cropland, the aproches of planting Medicago sativa L. and Artemisia L. can bring on the increase of the number of soil animal groups and individuals. Also it can increase the number of species and individuals of detritivorous scarab.3. The number of soil macrofauna groups and individuals in different soil layers is higher than that of in planting Medicago sativa L., in planting Medicago sativa L. and Artemisia L., and in planting Artemisia L. and Helianthus tuberosus L.. After conversion of cropland to grassland, the number of soil micro- and mesofauna individuals in different soil layers are increased.4. Based on the analysis of five biodiversity indice, the macrofauna community biodiversities are increased in three sample sites which planting Medicago sativa L., planting Medicago sativa L. and Artemisia L., and planting Artemisia L. and Helianthus tuberosus L.. 5. Analysis on the soil nutrition showed that the content of soil total nitrogen, phosphorus and soil organic matter in Medicago sativa L. Planting sample site are all higher than that of other sites. So after grassland restoration of farmland, planting Medicago sativa L. may lead to the evident improvement of soil nutrient.6. The omnivorey groups of soil macrofauna is common in all investigated sites. While after grassland restoration of cropland, the phytophagous groups are increased in Planting Medicago sativa L. site, and in planting Medicago sativa L. and Artemisia L. site. The predatism groups is more in planting Helianthus tuberosus L. site, and in planting Artemisia L. and Helianthus tuberosus L. site.In a word, it is the best approaches of grassland restoration of cropland that planting Medicago sativa L. or planting Medicago sativa L. and Artemisia L. after de-farming in Wuchuan region, Inner Mongolia.