玛纳斯河流域荒漠草地沙化遥感监测研究

Study on Remote Sensing Monitoring of Desert GrasslandDesertification in Manasi River Basin

以1989—2016年玛纳斯河流域TM/OLI遥感影像为数据源,利用混合像元分解技术,计算玛纳斯河流域草地总覆盖度和裸沙面积。在此基础上通过监测年与基期年的比较,计算草地覆盖度相对基期年的减少率和裸沙面积相对基期年的增加率两个监测指标,依据《天然草地退化、沙化、盐渍化的分级指标》(GB 19377—2003),对计算出的两个指标分别进行沙化等级评定和赋值,将两种评定结果相综合来监测草地沙化。结果表明,玛纳斯河流域近30年来荒漠草地沙漠化总体呈现先增加后降低的趋势。分析表明,玛纳斯河流域草地沙化是人为和自然因素双重作用的结果。

In this paper,the total grassland coverage and the bare sand area in Manasi River basin were calculated by TM/OLI remote sensing images from 1989 to 2016 and mixed pixel decomposition technology.On this basis,comparing with the base year,the decrease of grassland coverage and the increase of bare sand area were figured,rated and assigned according to“Parameters for degradation,sandification and salification of rangelands”(GB 19377—2003),and were combined to evaluate and monitor the grassland desertification.The results showed that the desert grassland desertification in the study area increased at first and decreased later in the last 30 years.The grassland desertification was the dual effects of human and natural factors.