基于遥感生态指数的新疆干旱区博乐市生态变化分析

Ecological Change Analysis of Bole City in Arid Regions of Xinjiang Wei Autonomous Region Based on Remote Sensing Ecological Index

[目的]结合遥感方法分析新疆维吾尔自治区博乐市生态变化,为该区生态保护提供理论依据。[方法]以博乐市1997年、2007年和2016年3期Landsat系列影像为数据源,提取绿度、湿度、干度和热度4个指数,通过主成分分析耦合出遥感生态指数(RSEI),对博乐市生态环境质量进行了监测和评价。[结果]研究区属于MODS(山地—绿洲—荒漠)系统,总体RSEI指数较低,由差和较差主导;1997—2016年博乐市的生态环境质量呈明显改善趋势,遥感生态指数RSEI从0.250提高到0.422,等级为优和良的比例从11.24%上升到26.20%;改善的区域面积明显大于变差的面积,改善的区域主要分布在北部山地、中部绿洲和南部天山西部北麓荒漠区域。生态环境恶化的区域主要集中在中部绿洲的耕地和城镇建设用地区域。[结论]荒漠生态建设和扩大绿洲面积对生态环境的改善有积极影响,同时也要合理配置资源和土地利用。

[Objective]This study is to analyze the ecological change in Bole City of Xinjiang Wei Autonomous Region by remote sensing method,in order to provide a theoretical basis for ecological protection.[Methods]The Landsat images of Bole City in 1997,2007 and 2016 were collected as data sources,and four indexes including greenness,humidity,dryness and heat were extracted.The principal component analysis was applied to couple the remote sensing ecological index(RSEI),to monitor and evaluate the ecological environment quality of Bole City.[Results]The research area belongs to the mountain-oasis-desert system(MODS),and the overall RSEI was very low in 1997,2007 and 2016.The ecological environment quality of Bole City showed a significant improvement trend from 1997 to 2016,as the RSEI increased from 0.250 to 0.422 and the proportion of excellent and good leveles increased from 11.24% to 26.20%.The improved areas were mainly distributed in the northern mountains,the central oasis,the Southern Tianshan Mountains and the western deserts at the northern foot,which were significantly larger than the degraded area.The deteriorated areas were mainly concentrated in the cultivated land and urban construction areas in the central oasis.[Conclusion]The construction of desert ecology and the expansion of oasis have a positive impact on the improvement of ecological environment.In addition,rational resource allocation and land utilization should be carried out as well.