Evaluation of historical and future wetland degradation using remote sensing imagery and land use modeling

In recent decades, rapid urbanization and climate change have led to the degradation of many coastal wetlands, impairing their ecosystem functions and services. However, few studies have analyzed how these historical degradation trends will continue into the future, especially in rapidly developing regions. Here, we quantified the long‐term wetland degradation from 1984 to 2016 in Hangzhou Bay and then developed land use simulation models to predict the spatial locations of wetland degradation to 2046 under different scenarios. Key findings include the following: (a) there was a statistically significant decreasing trend for the natural wetlands of ~10 km² yr⁻¹ on average from 1984 to 2016; (b) after the establishment of an economic development zone in 2001, the degradation rate more than quadrupled, accelerating from ~4 to ~18 km² yr⁻¹; and (c) if the high degradation rate continues (the economic development scenario), then the coastline will move approximately 5.89 km inland, significantly undermining the protections against sea level rise. In contrast, in the wetland protection scenarios, the projected degradation could be mitigated by ~20%. The proposed framework to reveal the key historical drivers of degradation and potential future protection strategies of wetlands provides much needed insights and tools for protection of other coastal wetlands undergoing rapid development.