香格里拉大峡谷土壤资源现状分析

对云南西北部横断山系的香格里拉大峡谷土壤资源利用现状、土壤特性以及土壤利用格局改变对生态环境造成的影响进行了研究，结果表明：香格里拉大峡谷土壤类型多样，林下土壤土层深厚，粘粒含量高，养分丰富．土壤发育过程以高山寒冷环境下的有机质积累为主，有机炭含量较高，20cm以下的土壤深层仍高达7．3％．尽管气候寒冷使土壤利用性能受到限制，但开发为农业利用土壤后表层土壤有机质平均含量从12．1％降至2．9％，耕后的撂荒地下降了5倍，过牧超载、自然干扰如火灾也引起土壤养分下降．针对土壤退化状况和土壤生态环境的脆弱性，提出了香格里拉大峡谷土壤资源可持续利用的保护对策和措施．

Study on Utilization Status of Soil Resources in Shangri-la Gorge,Southwest Yunnan

The characteristics and utilization status of the soils, and the impacts of different utilization on ecosystem in Shangri-la Gorge were discussed. The results showed that there was a rich diversity of soil types in the gorge area with high clay and nutrient contents. The present soil formation in Shangri-la is mainly in organic matter accumulation process under cold alpine environment. The average content of organic matter is high and this index of the subsoil below 20 cm still reaches 7.3%. The average content of organic matter in surface soil dropped to 2.9% from 12.1% after cropping though the utilization of the land is limited by the cold climate in the gorge area. The same index of abandoned cropland dropped to about 20% of the contrast. Overgrazing, natural disturbance such as forest fire also caused reduction of nutrient content of the soil. Some protective measures and related tactics for sustainable utilization of the soil fertility in Shangri-la Gorge area are put forward based on understanding of the soil degradation and the ecological fragility of the soil.