基于Landsat的重庆市生态环境质量动态监测及其时空格局演变分析

长江流域是我国重要的生态屏障之一，重庆市作为长江上游最后一道关口，研究其生态质量发展对于有效保护长江流域生态环境具有重要指导意义。基于2011—2021年间的Landsat影像等数据，计算遥感生态指数(Remote sensing based ecological index, RSEI),并采用Sen(Theil-Sen median)趋势分析法和MK(Mann-Kendall)检验研究其变化趋势以及利用Hurst指数模型分析RSEI的持续特征。利用空间转移矩阵和重心迁移模型研究其在空间上分布特征的变化情况，最后使用降水、风速、近地表气温、海拔等辅助数据为影响因素，结合地理探测器进一步探究RSEI变化驱动力，探讨重庆市2011—2021的RSEI空间分布及演变趋势。结果表明：(1)重庆市多年平均RSEI为0.593,使用等间距法将其划分的等级为差、较差、中等、良、优的面积占比分别为2.48%、8.28%、38.32%、41,87%、9.05%。从整体来看重庆市生态质量水平较高，重庆市年际RSEI以显著趋势波动增长。(2)RSEI等级为差的地区空间上主要集中于重庆西部；较差等级主要围绕...

Dynamic monitoring and spatio-temporal pattern evolution analysis of eco-environmental quality in Chongqing based on remote sensing

In this study, we take Chongqing, an upstream city of the Yangtze River as the study area. This paper calculated the Remote sensing-based ecological index (RSEI) based on Landsat images from 2011-2021 and utilized Theil-Sen estimator and MK (Mann-Kendall) test to study its trend. In this study, the long-term dynamics of RSEI were analyzed within the Hurst index model. The spatial shift matrix and the center of gravity shift model were used to investigate the changes in the spatial distribution characteristics of RSEI. Finally, the auxiliary data such as precipitation, wind speed, near-surface air temperature, and elevation were used as influencing factors and combined with geographic probes, these factors were included in the further investigation of the driving forces of RSEI changes; This investigation shall indicate the spatial distribution and evolution trends of RSEI in Chongqing from 2011 to 2021. The results showed that:(1) the multi-year average RSEI of Chongqing was 0.593, and the percentages of areas classified as poor, relatively poor, moderate, good, and excellent using the equal spacing method were 2.48%, 8.28%, 38.32%, 41,87%, and 9.05%, respectively. As a whole, the ecological quality level of Chongqing was high, and the interannual RSEI of Chongqing was increasing with a significant trend fluctuation. (2) The areas with poor RSEI grades were spatially concentrated in western Chongqing; the relatively poor grades were mainly around the poor level; the medium grades were mainly located in the central and western Chongqing; more than half of the areas with good or excellent RSEI grades were distributed in the central and northern Chongqing. (3) The results produced in Theil-Sen estimator and Hurst index model were analyzed using the ArcGIS overlay, indicating that a total of 53.3% of the overall RSEIs that would remain sustainable in terms of growth. (4) From the factor detection, natural factors, mainly near-surface temperature and elevation, and anthropogenic factors, mainly land use, were the main influencing factors on the spatial distribution of RSEI in Chongqing. (5) During the course of ten years, the spatial distribution of RSEI saw general improvements in all surveyed groups, and the overall ecological environment of Chongqing was optimized.