基于GEE的石嘴山地区生态环境质量时空演变特征研究

Spatial and temporal evolution characteristics of ecological environment quality in Shizuishan region based on GEE

以石嘴山市为研究对象,基于GEE平台选取30年的Landsat影像数据,提取绿度、湿度、干度、热度,并加入符合地区特点的盐碱度指标共同构建改进后的遥感生态指数(RSEI),采用长时间序列的趋势分析方法,对1991—2021年石嘴山地区的生态环境变化进行综合评价。1991—2021年研究区的RSEI指数与绿度、湿度呈正相关,与盐碱度、干度、热度呈负相关,生态环境质量呈现出“下降-快速上升-缓慢上升”的趋势。1991—2021年石嘴山市的生态环境质量呈明显改善趋势,生态环境质量显著上升区域面积为4787.8 km^(2),占比71.0%,显著下降区域面积为117.4 km^(2),占比1.7%。在1991—2021年,除主城区及周边地区生态环境质量下降以外,其余地区较之前都有明显上升,尤其是在沙湖以及黄河两侧。研究表明区域生态环境质量下降的主要原因是城市扩张,上升的主要原因是内陆湖以及土壤盐渍化改良工程对生态环境的积极改善作用。

Taking Shizuishan city as the research object,Landsat image data of 30 years were selected based on GEE platform to extract greenness,humidity,dryness and heat.The improved remote sensing ecological index(RSEI)was constructed by adding salinity-alkalinity indexes suitable for regional characteristics,and the long-term trend analysis method was used to comprehensively evaluate the ecological environment changes in Shizuishan area from 1991 to 2021.From 1991 to 2021,RSEI index was positively correlated with greenness and humidity,but negatively correlated with salinity,dryness and heat.Ecological environmental quality showed a trend of“declining-rapidly rising-slowly rising”.From 1991 to 2021,the eco-environmental quality of Shizuishan city showed a trend of obvious improvement.The area of eco-environmental quality significantly increased was 4787.8 km 2,accounting for 71.0%,while the area of eco-environmental quality significantly decreased was 117.4 km 2,accounting for 1.7%.From 1991 to 2021,except for the decline of ecological environment quality in the main urban area and its surrounding areas,the other areas,especially in the Sand Lake and both sides of the Yellow River,have significantly improved.The main reason for the decline of ecological environment quality in the study area is urban expansion,and the main reason for the increase is the positive effect of inland lake and soil salinization improvement project on ecological environment.