Ecological degradation in the Inner Mongolia reach of the Yellow River Basin, China: Spatiotemporal patterns and driving factors

The ecological conservation and high-quality development of the Yellow River Basin (YRB) has been the prime strategy of China. Wherein, the Inner Mongolia reach of the Yellow River Basin (IM-YRB) is a critical ecological barrier in northern China, playing an unshakable position in ecological and food security in the YRB. However, evaluation of ecological conditions and relevant driving factors have not aroused considerable concerns. Here we propose an ecological degradation index system based on the Pressure-State-Response (PSR) multi-scale comprehensive assessment framework and evaluate the ecological environment degradation intensity in the IM-YRB during 2000 to 2018. We find continual degradation of the ecological environment with increasing degradation intensity in the IM-YRB during 2000 to 2018. Moreover, we quantify that 24.16% of the IM-YRB had highly significant degradation (99% confidence level) of the ecological environment. The areas with significant degradation (95% confidence level) of the ecological environment accounted for 57.19% of the IM-YRB. The population density, land use, coal mining and fires are the main influencing factors behind ecological environment degradation in the IM-YRB. In addition, there occurred widespread land use conversion (>50% of the study region in area) amongst grassland, arable land, sands, construction land and unused land and these land conversions can be found mainly in the Yinshan Mountains (from grassland to abandoned land, the Hetao Irrigation District (from grassland to arable land) and the Kubuqi Desert (from sand, arable land and unused land to grassland). This study acts as the theoretical ground for sustainability and conservation of the regional ecological environment.