1990—2021 年内蒙古遥感生态环境质量变化及趋势分析——以呼伦贝尔市陈巴尔虎旗为例

he ecological civilization construction in Inner Mongolia, an important ecological barrier in northern China, is important for national ecological security, the stability of the border areas, and the sustainable economic and societal development of the minority areas. In this study, we extracted four key indices based on long-term satellite observations to describe the quality of the ecosystem. We constructed the remote sensing ecological index (RSEI) through principal component analysis. Furthermore, we adopted the Mann-Kendall (M-K) trend test for analyzing the changes in ecological quality in the Hulunbuir grassland of Inner Mongolia from 1990 to 2021. The RSEI can comprehensively reflect the quality of the ecological environment, and results revealed that the quality of grassland in Inner Mongolia has improved in the past 30 years, with an increasing trend of 0.0037 every year (P < 0.01; R2 = 0.39). The significant increasing trend of RSEI and the improved ecological quality from 2012 to 2021 was further verified through the M-K trend significance test. A single factor cannot fully characterize regional ecological quality so, four factors i.e., greenness, dryness, humidity, and heat were included in RSEI. The space quality showed a gradual improvement from west to east, with lower RSEI for grassland in the west compared with that for forest and farming areas in the east. A similar trend for quality was observed with the variation of the vegetation coverage. This study enriched the assessment methods of grassland ecological quality in Inner Mongolia, which can provide an important reference for the ecological protection, restoration, utilization, and sustainable development of meadow steppe in Inner Mongolia.