Natural Reserves Exposure to Rainstorm in the Eastern Monsoon Region of China

In the context of global warming, extreme precipitation events have become increasingly severe. The establishment of natural reserves does not perfectly protect rare animal species from the adverse effects of extreme rainfall. Developing a risk assessment system for heavy rainfall exposure in natural reserves can identify those at heightened risk during precipitation events. This research utilizes observational data from meteorological stations from 1971 to 2020 to reveal spatiotemporal trends of heavy rainfall in the eastern monsoon region of China and establishes an exposure risk assessment framework to evaluate future scenario risks for natural reserves. Results indicate that the annual average number of heavy rainfall days gradually increases from northwest to southeast, displaying a distinct zonal distribution pattern. The proportion of heavy rainfall days to total precipitation days and the average intensity of heavy rainfall show peak centers in the southeastern coastal areas, western Sichuan region, and North China Plain, with minimum values observed in the northwestern direction. Protected areas in China's Eastern Monsoon Region display a north-south gradient of precipitation exposure risk that intensifies from near (2031–2050) to far (2081–2100) future under SSP245 scenario, with highest vulnerability in southeastern coastal areas. National reserves generally experience lower exposure than provincial and municipal ones, though all categories face increasing precipitation risks over time.