基于RSEI的乌鲁木齐市生态环境质量时空演变研究

Study on the Spatial and Temporal Evolution of Ecological Environment in Urumqi Based on RSEI

利用中分辨率成像光谱仪(MODIS)遥感影像数据,通过谷歌地球引擎(GEE)平台构建了乌鲁木齐市2003—2022年的遥感生态环境指数(RSEI),并采用泰尔-森(Theil-Sen)中位数法和曼-肯德尔(Mann-Kendall, MK)检验方法对RSEI的时空变化趋势进行了分析。结果表明:(1)乌鲁木齐市2003—2022年的RSEI平均值为0.37,整体生态环境质量处于中等偏下水平。RSEI表现出明显的空间差异,呈现出自南向北递减的空间变化趋势。(2)2003—2022年,乌鲁木齐市整体RSEI上升趋势值为0.02/10 a。具体来看,增长趋势主要集中在2003—2016年间,RSEI增长率为0.07/10 a。2003—2016年,RSEI呈现波动增长的趋势,但2016—2022年间,RSEI呈现显著下降趋势,下降率为0.21/10 a。(3)2003—2022年间,乌鲁木齐市RSEI下降区域主要分布在南部(乌鲁木齐县南缘)以及东部(达坂城东北部),RSEI增长区域主要分布在中部以及北部(米东区)。从2016—2022年RSEI的变化趋势来看,中部和北部的RSEI有下降趋势,后期应重点关注这2个区域的生态环境改善。

This paper investigated the remote sensing ecological index(RSEI)over Urumqi from 2003 to 2022 based on MODIS remote sensing data and the Google Earth Engine(GEE)platform.Then,the Theil-Sen Median and Mann-Kendall methods were used to analyze spatio-temporal variations of RSEI.The results showed that:(1)The average RSEI of Urumqi from 2003 to 2022 was 0.37,suggesting a slightly lower level of overall environmental quality.The RSEI exhibited significant spatial differences,with a spatial trend of gradual decrease from south to north.(2)From 2003 to 2022,the overall RSEI of Urumqi showed a trend of increasing by 0.02 every 10 years.Specifically,the increasing trend occurred mainly in the period of 2003—2016,with a rate of 0.07 per 10 years.(3)During the period from 2003 to 2022,the RSEI of Urumqi exhibited a decrease in the southern region(southern edge of Urumqi County)and the eastern region(northeastern part of Dabancheng),and an increase in the central and northern regions(Midong).However,from 2016 to 2022,the RSEI showed a decreasing trend in the central and northern regions,calling for attention on improving the ecological environment in these areas in the future.