塔里木河下游植被覆盖动态变化遥感分析

Remote sensing analysis on the dynamic change of vegetation coverage in the lower reaches of Tarim River

目的基于遥感等信息化技术,对塔里木河下游地区应急输水前后的植被覆盖度状况进行动态监测及定性定量分析。方法选取塔里木河下游地区1999年TM、2002年ETM+和2004年的ASTER等3期夏季遥感影像和基础地理数据,基于RS,GPS及GIS等技术,通过分类体系划分、遥感信息提取、野外验证等方法,完成了研究区植被覆盖度的动态变化分析。结果应急输水工程实施后,研究区河道两侧较大范围内的中、高盖度植被覆盖面积明显增加,劣、低盖度植被覆盖面积持续下降,部分地区还出现了较为明显的逆转,生态环境逐步趋于好转。结论基于RS,GPS及GIS等信息技术,建立植被覆盖度动态监测体系,是研究生态环境动态变化的重要手段和发展趋势。

Aim Based on the information technology of remote sensing（RS）,the factor of the vegetation coverage sensible to the ecological change before and after the emergent water transportation project in the lower reaches of the Tarim River is monitored dynamically and analyzed in a qualitative and quantitative way.Methods Three periods of the multi-source and multi-type RS images such as TM image,ETM＋image and ASTER image are collected from the summer of 1999,2002 and 2004,respectively,together with the basic geographic data in the target research.The information technologies of remote sensing（RS）,global positioning system（GPS） and geographic information system（GIS）,etc are applied,the framework of system classification,remote sensing extraction and interpretation as well as field investigation are opted to be used in the implementation of the dynamic analysis of vegetation coverage.Results The research indicates that with the practice of Emergent Water Transportation Project,the moderate and satisfactory coverage of vegetation on both sides of the lower reaches of Tarim River evidently go up,the poor and lower vegetation coverage areas constantly fall into decline,and some turn for worse is prevented and stopped in some area.The ecological environment of target research gradually tends to improvement.Conclusion Based on the information technologies such as RS,GIS,GPS,the establishment of vegetation coverage dynamic monitoring system,is an important means and development trend on the study of ecological environment dynamic change.