A Temporal Dynamic Assessment of Eco-environmental Quality in Guangxi, China(2000–2020), Based on GEE and RSEI

As a representative ecologically vulnerable zone, Guangxi Zhuang Autonomous Region necessitates systematic quantification of spatiotemporal eco-environmental dynamics to inform conservation governance.Leveraging Google Earth Engine (GEE), this research constructed a MODIS-derived Remote Sensing Ecological Index (RSEI), supplemented by spatial autocorrelation diagnostics to decode change patterns.The findings demonstrate that: (1) the average RSEI values across the years 2000, 2005, 2010, 2015, and 2020 were 0.677, 0.663, 0.782, 0.741, and 0.767, respectively, suggesting a declining trend in ecological quality during 2000-2005, followed by an overall improvement from 2010 to 2020.(2) LISA cluster mapping revealed predominant high-high (H-H) aggregations in the study area's northeastern sector, contrasting with concentrated low-low (L-L) clusters encircling Nanning and territories contiguous to Guangdong Province.(3) From 2000 to 2020, the area classified as "Critical" decreased by 303.5 km, "Suboptimal" areas declined by 4,108 km, "Marginal" areas by 26,178.25 km, and "Acceptable" areas by 49,679.5 km, while "Optimal" areas increased by 79,859.75km, indicating an overall shift toward higher ecological quality.(4) Elevation and slope were found to be the most crucial factors affecting RSEI changes from 2000 to 2020.