关键词: 金沙江干热河谷, 土地荒漠化, 评价因子, 评价指标, 评价方法

Abstract: Land desertification assessment is an issue of important theory of land desertification study. The assessment principle is proposed through the study on characteristic, formation mechanism and influencing factors of the land desertification in the dry-hot valley area of Jinsha River. Based on analysis of factors' loading to land desertification, three main influencing factors (including five assessment indexes): geomorphology (cutting density, slope), soil (soil thickness, soil organic matter content) and vegetation (vegetation index) are selected. Quantitative classification of each assessment index is proposed through investigation into many sample plots and analyses and calculation. The assessment index system of land desertification in the dry-hot valley area of Jinsha River is firstly raised. The degrees of land degradation/desertification are determined by element analysis and multiplayer fuzzy evaluation in accordance with the complexity and fuzziness of land ecological system. The evaluation result can not only tell us the degree of land degradation/desertification, but also tell us its developing tendency and provide scientific basis and support of policy decision for the prevention and control of land degradation/desertification.

Key words: dry-hot valley of Jinsha River, land desertification, evaluation, index, method