干旱区绿洲遥感生态指数的改进

Improvement of remote sensing ecological index in oasis in arid area

针对干旱绿洲地区的生态环境复杂,生态环境质量难以通过遥感指数评价的问题,该文从生态因子选择与耦合方法两方面对遥感生态指数(RSEI)进行了优化,构建了绿洲遥感生态指数(ORSEI)。该文研究了2020年民勤县RSEI、干旱遥感生态指数(ARSEI)和ORSEI在细节表征方面的差异,并通过ORSEI指数对2015—2020年生态环境进行了监测与评估。研究发现,ORSEI指数提升了原遥感生态指数在干旱绿洲地区的表现力,能更精准地监测民勤县生态环境。2015—2020年生态环境总体较差,生态环境等级较高的地区主要分布在绿洲地区,绿洲扩张使生态环境质量有很大的提升,西北地区山地生态环境改善情况较为明显,沙漠腹地生态环境很差且变化复杂。

In view of the complex ecological environment in arid oasis areas and the difficulty of evaluating the quality of ecological environment based on remote sensing index, the remote sensing ecological index remote sensing ecological index(RSEI) was optimized from the aspects of ecological factor selection and coupling method;the oasis remote sensing ecological index(ORSEI) was built;the differences in detailed characterization among RSEI,arid remote sensing ecological index(ARSEI) and ORSEI of Minqin county in 2020 were studied;the ecological environment from 2015 to 2020 was monitored and evaluated by the ORSEI index. The results showed that the performance of original remote sensing ecological index in arid oasis areas was improved through the ORSEI index, which could monitor the ecological environment of Minqin county more accurately. The ecological environment was generally poor from 2015 to 2020. The areas with higher ecological environment were mainly distributed in oasis areas. The expansion of oasis had greatly improved the quality of ecological environment. The improvement of ecological environment of mountains in the northwest was more obvious, and the ecological environment in the hinterland of desert was poor and changed complicatedly.