[Trend and Driving Factors of Coastal Wetland Fragmentation in China].

Abstract

Analyzing the spatial and temporal trends and driving mechanisms of coastal wetland fragmentation is of great significance for wetland protection and even blue carbon function enhancement. Taking the coastal wetlands of China as the research area， this study utilized Fragstats to calculate regional landscape pattern indices and analyzed the characteristics of landscape pattern evolution and the degree of fragmentation. Additionally， the optimal parameter Geodetector was employed to identify the driving factors influencing the fragmentation of coastal wetlands. The results follow： ① Over the past 20 years， the area of coastal wetlands in China decreased by a total of 660 877.73 hm²， with the rate of degradation initially intensifying and then slowing. The area of tidal flat and coastal aquaculture pond decreased significantly， while the area of mangrove and saltmarsh increased with fluctuation. ② In 2000-2015， the fragmentation of coastal wetlands in China was severe， but the trend eased in the following five years. ③ From 2000 to 2010， the regions with increased fragmentation were mainly concentrated in southern Liaoning Province， Tianjin， northeastern Shandong Province， eastern Zhejiang Province， southwestern Guangdong Province， Hainan Province， and western Taiwan. Between 2010 and 2015， the fragmentation of coastal wetlands expanded significantly nationwide. From 2015 to 2020， the trend of coastal wetland fragmentation slowed， and the fragmented areas decreased. ④ Changes of total population， GDP， and impervious surface area were the main driving factors leading to the fragmentation of the coastal wetland landscape. The synergistic effect of temperature and total population presents the strongest explanatory power， emphasizing the importance of relieving urban population pressure in mitigating coastal wetland fragmentation in the context of global warming. This study provide scientific references for the management and sustainable development of coastal wetlands in China.