The Xiamen Symposium on Marine Environmental Sciences (XMAS 2025)

Given the accelerating rate of global biodiversity loss, prioritizing marine areas for protection presents a significant conservation challenge. Climate-driven shifts in marine species distributions are occurring with complex three-dimensional components, complicating the development of effective spatial protection plans. Biodiversity conservation needs to simultaneously consider not only spatial extents and depths but also temporal dimensions to accommodate the effects of climate change.
In this study, we used data on 8,452 marine species across four depth domains to develop a three-dimensional marine planning approach aimed at identify priority conservation areas within the adjacent seas of China. First, we employed a multiparameter environmental envelope model, along with climate velocity trajectories, to project current and future distributions of target species under three CO₂ emission scenarios (RCP2.6, RCP4.5, RCP8.5) up to the year 2100. Then, we utilized a spatially explicit vulnerability index to assesses the relative vulnerability of species to climate change. Finally, we estimated the minimum sea area required to conserve biodiversity, secure key biodiversity areas, minimize species’ exposure to climate change, and reduce conflicts with fishing.
Our results show that the core habitat area will decline for most species, resulting in an average net loss of 38.4% for all species in 2100 under RCP 8.5. This decline is accompanied by poleward expansions of the leading and trailing edges and center of gravity of species distributions. By 2100, <1%, 15.6%, and 53.3% of China’s marine areas will no longer be suitable as core habitats for at least half of their current species under RCP 2.6, RCP 4.5, and RCP 8.5, respectively. Vulnerability varies significantly among different taxonomic groups. In general, species with restricted distribution ranges and those inhabiting upper ocean layers exhibit higher vulnerability. The resulting three-dimensional, climate-smart conservation area encompasses 12.6% of China’s adjacent sea, representing a low-regret option to serve as the foundation for developing a comprehensive marine protected area network in China. New low-regret conservation priorities have been identified across all of China’s seas, although the extent of these priorities varies considerably among regions. East sea of Liaodong Peninsula and West Guangxi Sea exhibit the largest area of conservation priorities relative to area size, with over 70% of these seas covered by new priority areas. Our findings provided a solid scientific reference for three-dimensional prioritization across the China seas under a warming ocean.
 

Climate change,Spatial conservation planning,Vertical connectivity,Conservation goal,Climate vulnerability assessment