Climate change threatens the distribution of Liriodendron chinense: Evidence from China

Studying the potential responses of protected species to global climate change is important for conserving biodiversity. The decline and dieback of Liriodendron chinense Sarg. (L. chinense), an ancient tree species with high ecological and economic value, have been observed in recent years. We aimed to explore the main environmental variables affecting this plant habitat and its future distribution using maximum entropy (MaxEnt). Bioclimatic variables derived from eight Coupled Model Intercomparison Project 6 models, combined with 363 species occurrence records, and multiple environmental factors, were used to predict the potential distribution of the species in the mid and late 21st century under shared socio–economic pathway (SSP) scenarios 126, 245, and 585. The MaxEnt model yielded an excellent performance with an area under the curve value of 0.95. Precipitation in the driest month was the greatest contributor (50.33 %) to habitat distribution, and the Human Influence Index provided indispensable environmental information for the prediction. The habitat loss area was the largest in SSP585-2090s (915,652 km2) and the smallest in SSP126-2090s (271,989 km2). In contrast, the gain area was the largest under SSP126-2090s (18,060 km2), which mainly occurred in the Yangtze River basin (10,625 km2). The SSP126 scenario was the most favorable pathway for the survival of L. chinense, with the most habitat area gained and the least habitat area lost, in which the habitat range showed a notable trend of northward migration in the 21st century. An extreme warming scenario will threaten the habitat of L. chinense, which will have sparse refuge mainly in the Yangtze River and Southeast River basins by the 2090s. These results provide a theoretical basis for developing policies to conserve L. chinense in the face of future climate change.