Projected degradation of Quercus habitats in Southern China under future global warming scenarios

Quercus species play a significant role in the ecosystems of southern China, possessing diverse ecological, economic, and cultural values. Predicting the suitable habitat of these species in southern China and assessing the impact of climate change on it is crucial for species conservation, ecological construction, and achieving China's carbon neutrality goals. This study selected seven common oak species in southern China and used a comprehensive habitat suitability model to simulate their Stand Potential Distribution Areas (SPDAs) under baseline conditions and different climate change scenarios over various periods. The results indicate that among the seven oak species, the SPDAs of six oak species linearly decreased with increasing temperatures, with the three species, Q. acutissima, Q. aliena, and Q. variabilis, having the largest SPDAs under baseline conditions exhibiting the most rapid declines with rising temperatures. Only Q. chenii showed a slow increase in SPDA with temperature rise. Additionally, regions with at least one species' SPDAs covering the all habitat area and regions with at least four species' SPDAs covering the core habitat area also significantly decreased with increasing temperatures. Therefore, climate change is expected to degrade the habitat of main deciduous oaks significantly in southern China, warranting attention and proactive management measures.