基于优化MaxEnt模型的黑籽重楼潜在适生区预测OA

[Objective]To predict the potential suitable area of Paris thibetica,explore the main environmental factors influencing its distribution,and analyze the spatial distribution pattern of the potential suitable area and the trend of the centroid transfer.[Method]The optimized MaxEnt model was used to predict the potential distribution areas under different climate conditions in the current and future four periods(2030s,2050s,2070s,2090s)based on 19 environmental factors and data of 143 distribution sites.[Result]The optimal parameter combination of MaxEnt model was regularization multiplier=0.5 and feature combination=LQ.The prediction accuracy was relatively high,with area under curve being 0.930.The temperature seasonal variation,the minimum temperature of the coldest month,the annual temperature range and the annual mean precipitation were the main environmental factors affecting the distribution of P.thibetica,with a cumulative contribution rate of 68.9%.Under the current climate background,the total suitable areas acreage of P.thibetica was 235.14×104 km2,accounting for 24.49%of China's total land area,and these areas were concentrated in the border areas of Yunnan,Guizhou,Sichuan and Tibet,as well as in Hunan,Hubei,Fujian and other regions.In the future,the suitable areas showed a pattern of"shrinking westward and retreating eastward".Under the SSP5-8.5 scenario,the acreage of suitable areas in the 2090s was only 48.34%of the current level,and the high-suitable area contracted toward alpine valleys.The centroid of suitable areas migrated northwestward along the Hengduan Mountains under the SSP1-2.6 scenario,and toward southeastern Tibet under the SSP5-8.5 scenario.[Conclusion]The ecological niche of P.thibetica is synergistically regulated by temperature and humidity variables.Projected climate warming will exacerbate suitable area fragmentation,with the Hengduan Mountains potentially functioning as a critical climatic refugium.These findings provide a robust scientific basis for P.thibetica's in-situ conservation,ex-situ conservation and germplasm resource bank establishment.