四川省石漠化敏感性评价及其空间分布特征

基于石漠化敏感性评价机理，运用GIS技术分别分析了岩溶地貌、坡度、植被覆盖、土壤类型对石漠化敏感性的影响及其空间分布特征。基于此，进行研究区石漠化敏感性的综合评价。结果表明:（1）研究区石漠化中度敏感性区域面积最大，占研究区面积的32.39%，其次为轻度敏感性区域（占26.75%），高度敏感和极敏感性区域也有较大面积的分布，其比例分别为17.50%和21.51%；（2）石漠化敏感性空间分布具有明显的地域差异，金沙江下游、大渡河中游、四川盆地南部周缘和川东平行岭谷是石漠化高度敏感和极敏感集中分布的地区，川西南山地区域内长江上游重要支流木里河、水洛河、雅砻江两岸、盐源盆地以及四川盆地大部分岩溶地区基本以轻度、中度敏感为主；（3）研究区石漠化现状与石漠化敏感性分布基本一致，数量特征表明这二者具有很好的对应关系，但在局部地区强度特征却表现出一定的差异。

Assessment on Sensitivity and Spatial Distributed Characteristics of Karst Rocky Desertification in Sichuan Province

Based on evaluation principle of the sensitivity of rocky desertification, karst landform distribution, terrain factors, vegetation coverage, soil type, and these effects on the sensitivity of rocky desertification and its spatial distribution characteristics in study area were analyzed by using GIS technology. Comprehensive assessment of the sensitivity of rocky desertification in the study area was conducted. The results showed that: (1) among all the rocky desertification regions over the karst areas, the largest areas were the moderate sensitive areas making up 32.39% of all study area, which were followed by the low sensitive areas (26.75%), the high sensitive areas and the extreme sensitive areas also occupied a large proportion, the ratios of the two areas were 17.50% and 21.51%,respectively; (2) there were obvious regional variation characteristics in spatial distribution of sensitivity of rocky desertification, the high and extreme sensitive areas were the middle reaches of Jinsha River, the lower reaches of Jinsha River, the large areas of middle and lower reaches of Dadu River, the periphery of south of Sichuan Basin and parallel range-gorge areas in the east of Sichuan Province. The low and moderate sensitive areas were Muli River(the most important branch of the upper reaches of Changjiang River in the mountain area of Southwest Sichuan), Shuiluo River, both banks of Yalong River, Yanyuan Basin and most of karst areas in Sichuan Basin; (3) the severity of rocky desertification in the research areas was basically consistent with its sensitivity distribution in general. The quantitative trait of this research area indicates that rocky desertification was well corresponding to the sensitivity of rocky desertification, but strength characteristics differ in certain areas.