Identifying Variations in Ecosystem Health of Wetlands in the Western Songnen Plain (2000–2020)

An accurate understanding of the spatiotemporal variations in wetland ecosystem health is beneficial for guiding sustainable management and achieving sustainable development goals. To overcome the limitations single indicator approaches, this study proposed a multi-dimensional evaluation system based on four aspects of wetland ecosystems: pattern, quality, service, and threats. Furthermore, based on the wetland distribution dataset and MODIS products, we constructed a comprehensive wetland ecosystem health index (WEHI) from 11 indicators and applied it to assess the variations in wetland ecosystem health in the western Songnen Plain from 2000 to 2020, suggesting wetland responses to climate change and human activities. Results revealed that wetland ecosystem health was affected by variability in both hydrothermal conditions and human threats. Across the region, wetlands were primarily classified as “fair” level (0.25 ≤ WEHI < 0.50) with 63% by area, while the “good” level (0.50 ≤ WEHI < 0.75) accounted for 37%. Although the WEHI increased from 0.44 in 2000 to 0.47 in 2020, the overall health status of wetlands still requires targeted improvements. This gradual recovery was largely attributed to a combination of reduced threats, warming temperatures, and increasing precipitation. Protected areas with larger WEHI played a critical role in maintaining ecosystem health. The evaluation system developed in this study offers a reference for the wetland health assessment at a broader scale. The findings in this study are expected to inform more effective management and conservation strategies of wetlands.