Abstract:
Objective This paper aims to analyze the potential distribution areas of extremely small population of endangered plant Acer catalpifolium in China today and in the future, reveal the distribution dynamics of A. catalpifolium under future climate change.
Method Taking A. catalpifolium as the research object, based on the existing A. catalpifolium distribution sites, climate data and altitude data, using the MaxEnt model and GIS technology to simulate the current, 2050s (2041−2060) and 2090s (2081−2100) (SSP126, SSP245, SSP370 and SSP585) distribution pattern of A. catalpifolium under climate scenarios, classify the fitness level and use the area under the receiver operating characteristic curve (ROC) (AUC) to evaluate the accuracy of simulation, analyze the contribution rate of climate variables with the knife-cut method to find out the dominant climate variables that restrict the distribution of A. catalpifolium; compare the geographic distribution of A. catalpifolium under different climatic conditions based on the distribution area ratio (Na) and the degree of habitat change (Ne) dynamic.
Result The main suitable areas for A. catalpifolium were distributed in southwestern China. The AUC values of the training set and the test set under the nine climatic scenarios were both greater than 0.995, indicating that the model simulation accuracy was extremely high. The warmest season rainfall, temperature seasonal variation standard deviation and altitude had the highest contribution rates, which were 56.1%, 18.2% and 10.9%, respectively.
Conclusion Under the background of climate change, A. catalpifolium will lose a large number of highly suitable areas, and the habitat fragmentation will be more serious than the trend. The medium-to-high intensity emission scenario SSP370 has little impact on the potential distribution area of A. catalpifolium. This study can provide a basis for the in-situ and ex-situ conservation of the endangered species of A. catalpifolium.