Spatiotemporal dynamics of ecosystem integrity in arid Northwest China: patterns and potential driving factors

Ecosystem integrity reflects an ecosystem’s capacity to maintain functional resilience despite human impacts and serves as a foundation for ecological sustainability. While assessment frameworks for ecosystem integrity are well-established for aquatic systems, approaches tailored to arid terrestrial ecosystem remain inadequate. This study developed an eight-indicator framework that integrates the Aridity Index and Nighttime Light data – critical factors for capturing both climatic constraints and human pressures beyond populated areas characteristic of arid regions. Analysis of regions with significant ecosystem integrity changes identifies soil erosion, aridity, population density, and nighttime light as the most influential drivers in arid ecosystems, with landscape fragmentation serving as both a symptom and amplifier of ecosystem instability. The framework was applied to Xinjiang, Northwest China, where spatiotemporal patterns from 2000 to 2020 were analyzed using Ordinary Least Squares for spatial trend estimation and Mann-Kendall tests for temporal trend detection. Results reveal a distinct north-south spatial gradient in ecosystem integrity, with 62% of the region showing measurable enhancement by 2020. Notably, the improvement phase during 2000–2010 coincided with the first phase of the “Grain for Green” program, while the recovery phase of 2015–2020 aligned with the launch of the new round Grain for Green program (2015) and the Ecological Conservation Redline policy (https://www.mee.gov.cn/). Ultimately, this study offers an approach for the arid ecosystem that avoids misinterpreting natural low productivity as degradation, ensuring that conservation resources are directed toward ecosystems under actual anthropogenic stress.