Spatiotemporal trends and the change detection of the yearly eco-environmental quality in the Yellow River Basin, China

As a critical ecological security and economic corridor in China, monitoring the ecological quality of the Yellow River Basin (YRB) is essential for China’s ecological protection and sustainable economic development. In this study, we constructed a modified Remote Sensing Ecological Index (MRSEI) to investigate the spatiotemporal dynamics of ecological quality in the YRB from 2001 to 2023. Meanwhile, we incorporated the Aridity Index (AI) and the temperature (T). Furthermore, Multiple Linear Regression and Random Forest models were employed to quantify the contributions of moisture (NDMI), urbanization (NDBI), and productivity (NPP) to ecological variance. Finally, land cover type conversion was employed to interpret ecological variations detected by the MRSEI dynamic ratio. The primary results are as follows: (1) Ecological quality in the middle reaches of the YRB significantly improved from 2001 to 2010, remaining relatively stable from 2011 to 2023. (2) No significant correlation was observed between temperature (T) and MRSEI, but significant correlations between Aridity Index (AI) and MRSEI were observed during 2001–2010 in the Windbreak and Sand Fixation Functional Zone (WSFZ, r2001−2010=0.520 ± 0.225, p < 0.01) and Soil Conservation Functional Zone (SCFZ, r2001−2010=0.467 ± 0.350, p < 0.01). (3) The dominant land cover conversion types include barred land-to-cropland conversion (3640.44 km2) and cropland/barren land-to-grassland conversion (3212.19 km2; 1507.25 km2) in regions where ecological conditions improved from 2001 to 2023. (4) Form 2001–2023, NDMI (Surface Moisture), contributes 52%-56% to ecological dynamics, while the water cycle budget exerts a governing influence on basin-wide ecological quality. This study offers critical insights for promoting ecological protection and sustainable development in the functional zones of the YRB.