铁橡栎的潜在分布区及其对气候变化的响应

Potential distribution area of Quercus cocciferoides and its response to climate change

利用MaxEnt模型对中国西南干热河谷代表树种铁橡栎(Quercus cocciferoides Hand.-Mazz.)的潜在分布区及变化进行研究。基于91条可靠的分布记录和7个生物气候变量的模拟结果显示:铁橡栎的现代潜在分布受气温因子(等温性、昼夜温差月均值和年均温)和降水因子(最干月份降水量)共同制约,等温性是影响铁橡栎现代潜在分布的首要因子。铁橡栎的潜在分布区与实际分布较为吻合,现代高度适宜区位于滇中高原和滇北—川南金沙江流域;末次盛冰期,高度适宜区位于滇中和滇东南,并向东南退却且核心分布区面积缩减;全新世中期,整体的分布范围相对稳定;未来(2070年),高度适宜区范围与现代高度适宜区基本一致,但中度和低度适宜区轻微向北扩张。滇东南和中南半岛北部可能是铁橡栎末次盛冰期的南部避难所,中国西南干热河谷可能是铁橡栎在冰期-间冰期迁移和扩散的重要通道。综合研究结果认为:应对分布在中国西南干热河谷的铁橡栎进行保护,尤其应重点保护位于滇东南的种群。

Potential distribution area and dynamic change of Quercus cocciferoides Hand.-Mazz.(a representative tree species in dry-hot valley of Southwest China)were studied by using MaxEnt model.Based on 91 reliable distribution records and 7 bioclimatic variables,the simulation result shows that potential distribution of Q.cocciferoides at present is constrained by both temperature factor(isothermality,monthly mean diurnal range of temperature,and annual mean temperature)and precipitation factor(precipitation of the driest month),and isothermality is the primary factor affecting its potential distribution at present.The potential distribution area of Q.cocciferoides is consistent with its actual distribution,and the highly suitable areas at present are located in plateau in Central Yunnan and Jinsha River watershed from North Yunnan to South Sichuan;in the last glacial maximum,high suitable areas are located in Central and Southeast Yunnan,and retreat southeastward and area of central distribution area decreases;in the mid-holocene,overall distribution area is relatively stable;in the future(in 2070),high suitable area is basically identical to that at present,but moderate and low suitable areas slightly expand northward.Southeast Yunnan and northern Indo-China Peninsula might be the south refuge of Q.cocciferoides in the last glacial maximum,and dry-hot valley in Southwest China might be the important passage for the migration and spread of Q.cocciferoides in the glacial-interglacial period.According to the comprehensive research results,Q.cocciferoides distributed in dry-hot valley of Southwest China should be protected,especially the population located in Southeast Yunnan.