The construction of desertification-hazard system for revegetation

1.利用20年来卫星影像资料，研究毛乌素桑迪的荒漠化与植被恢复状况。利用这些数据、专题地图和政府统计数据建立了地理信息系统。在荒漠化地区或稳定地区进行实地调查，利用卫星数据和GPS定位。对当地居民进行了访谈，并进行了植被和土壤调查。通过对调查结果和卫星数据的分析，确定了过度放牧是荒漠化的主要因素。当动物密度超过每公顷草地2头时，荒漠化加剧。高比例的山羊必然导致严重的荒漠化。同时，在农业村庄周围促进重新植被。应注意政府数据的使用，因为繁殖动物的统计报告过多。在利用同位素方法分析植物水分效率的基础上，结合水资源的可持续利用，讨论了植被恢复规划。臭柏的水分利用效率高于油蒿、柠条和旱柳。应通过使用这种高效用水的植物来抑制地下水的消耗。旱柳的根系比油蒿和锦鸡儿的根系更深，旱柳的耗水量大于油蒿和锦鸡儿。因此，灌木的保护能力应高于乔木。

1. The status of desertification and revegetation in the Mu-Us Sandy Land was studied on the 20 years changes of satellite images. GIS was constructed with this data thematic maps and governmental statistics. Field survey was conducted in the desertificated area or stable area, where we approached with the satellite data and GPS. Interview to local people was done, associated with vegetation and soil survey. The main factor of desertification was identified as over-grazing on the results of survey and the analysis of satellite data. Desertification was promoted when the animal density was more than 2 heads per 1 ha of grassland. High percentage of goat necessarily caused severe desertification. Inversely, revegetation was promoted in the surroundings of agricultural villages. Attention should be paid on the use of governmental data, since the statistics of breeding animals were reported excessively.2. The planning of revegetation was discussed with special reference to sustainable use of water resource, based on the analysis of water efficiency of plants using isotopic methodology. The water efficiency of Sabina vulgaris was higher than that of Artemisia ordosica, Caragana korshinskii and Salix matsudana. The consumption of groundwater should be suppressed by the use of such plants with high efficiency for water use. The water use of Salix matsudana was larger than Artemisia ordosica, and Caragana korshinskii, because the root system of this Salix was deeper than that of Artemisia and Caragana. Consequently, the conservative ability of shrubs should be higher than trees.