基于干燥度指数的辽西北土地风蚀荒漠化判别

在土地利用分类的基础上，剔除山地、丘陵、岗地、水域及建筑用地等类型，研究辽西北地区风蚀荒漠化问题，试图找到一条半湿润易旱的界线。研究以TM、MODIS影像为数据源，以多种植被指数为参考指标，运用决策树方法对研究区进行分类，结果显示：非荒漠化、轻度、中度、重度与极重度风蚀荒漠化面积分别占辽西北总面积的44．38％、25．...

Discrimination index of wind erosion desertification based on aridity index in northwestern Liaoning Province

Based on land use map,this paper excluded mountains,hills,water,and constructions,and studied wind erosion desertification in the northwestern part of Liaoning Province,with the purpose of finding a semi-humid drought-prone line.This paper took TM and MODIS images as data source and some vegetation indexes as index by using decision tree to classify the study area.The results showed that non-desertification,light,moderate,severe and extremely severe wind erosion desertification area accounted for 44.38%,25.15%,18.97%,9.34% and 2.16%,respectively.Meanwhile,this study used empirical formula k=0.16∑≥10℃/ r to calculate aridity,and then interpolated aridity values by using Kriging method.Comparing aridity line 1.1,1.15,1.2,1.25 and 1.3,we found:(1) Selecting line 1.2 meets the requirement of judging the extent of desertification in semi-humid areas.(2) Line 1.2 is better than other lines on distinguishing non-desertification,severe and extremely severe desertification,and arable land.(3) Field investigations showed that line 1.2 could be the boundary of loam and sand in the northwestern part of Liaoning Province,and have important practical significance.Thus,on the basis of classification results,selecting line 1.2 is reasonable in science and valuable in practice.