also destroy steppe vegetation when their populations are high. Food selection by the dominant species Dasyhippus barbipes, Myrmeleotettix palpalis, and Chorthippus dubius have been studied in both artificial and natural conditions (Li et al., 1983; Li and Chen, 1985). The dominant acridoids prefer Aneurolepidium chinense but will also feed on other plants.
Soil Animals and Microorganisms Researchers from Inner Mongolia University have studied soil animals and the soil microorganism ecology of the Xilingele region. He et al. (1988) identified 23 families of soil animals, belonging to 15 orders, 8 classes, and 6 phyla. Nematoda, Acarina, Coleoptera, and Formicidae of Hymenoptera were found to be dominant. The variety and number of soil animals are highest in the Aneurolepidium chinense steppe, lowest in Stipa grandis steppe, and intermediate in sandy land, meadow, retrogressive steppe, and artificial grasslands.
The study of soil microbial ecology begun in 1979 has covered seasonal changes and distribution in soil profiles (Liao et al., 1985), biomass dynamics (Liao and Zhang, 1985), and soil enzymatic activities (Liao et al., 1988; Zhang and Liao, 1990). These studies have shown that the density of microorganisms varies with the type and fertility of the soil, whereas their distribution in the soil horizon and the dominant groups alternate with the seasons. In both Aneurolepidium chinense and Stipa grandis dominant communities, the microbial biomass is highest for actinomycetes, intermediate for bacteria, and lowest for fungi.
Utilization and Conservation of Grassland Resources There have been many articles and reports on the principles of grassland utilization and conservation in Inner Mongolia (e.g., Yong, 1984; Liu et al., 1987; Jiang, 1989). Li et al. (1988) have done a thorough synthesis of work on the Xilingele steppe. All of these authors have identified existing problems in grassland utilization and made recommendations for improving the management of grassland resources. Their studies have shown that the fencing of degraded grasslands can aid restoration. For the typical steppe of Xilingele, appreciable improvement (especially the recovery of fine forage grasses such as Aneurolepidium chinense and Agropyron spp.) may occur in two to three years after fencing, and its natural ("normal") state can be approached in five years (Jiang, 1989). The cost of fencing is about 112 Renminbi (U.S.$24.00) per hectare (Jiang, 1989).
There have been some attempts to estimate the carrying capacity of grasslands in the Baiyinxile State Farm, based on data for forage productivity, stocking rate, and animal consumption rate (e.g., Jiang, 1988; Li, 1990). These studies have brought together quantitative data that could be used to develop systems models for grassland resource management in this area. Although still incomplete, this data set is probably better than that available for any other grassland area in China. Li (1990) has developed a simple, static model that may stimulate future work in this direction.