气候变化对柴胡与狭叶柴胡适生分布的影响

Prediction of distribution pattern and change of suitable areas of Bupleurum chinense and Bupleurum scorzonerifolium under climate change in China

研究气候变化下物种适生区的分布格局与变迁,对于物种的保护和资源的可持续利用具有重要的理论和实践意义。选取柴胡(Bupleurum chinense)与狭叶柴胡(Bupleurum scorzonerifolium)在中国地域内的381个有效分布点和36个环境因子,利用MaxEnt模型模拟当前以及未来(2050和2070年)两种气候情景下(RCP4.5和RCP8.5)其适生区的分布格局,并分析了制约其适生区分布的主导环境因子。结果表明:(1)影响柴胡适生区分布的主导环境因子为最湿月份降水量、最干季度平均温度以及海拔。影响狭叶柴胡适生区分布的主导环境因子为最湿月份降水量、温度季节性变化标准差以及海拔;(2)当前气候条件下,柴胡适生区总面积为1.4755×10^(6)km^(2),约占我国国土面积的15.37%,中、高度适生区主要分布在陕西南部、山西东部、甘肃东南部、山东中部、河北中西部等地;狭叶柴胡适生区总面积为1.8034×10^(6)km^(2),约占我国国土面积的18.78%,中、高度适生区主要分布在黑龙江西部和东部、内蒙古中部和东北部、河北北部、陕西中部等地。(3)未来气候背景下,两种柴胡总适生区面积呈现增加趋势。柴胡适生区分布质心向东北方向的高纬度地区迁移,狭叶柴胡适生区分布质心向西部方向的高海拔地区迁移。

It is of great theoretical and practical importance to study the distribution patterns and changes of species suitable geographical distribution areas under the background of climate change for the protection of species and the sustainable use of resources. In this study, 381 effective distribution sites of Bupleurum chinense and Bupleurum scorzonerifolium in China(excluding duplicate, invalid and cultivated distribution sites) and 36 environmental factors(terrain, soil and climate data) were selected. Baesd on the data mentioned above, the spatial distribution patterns of the suitable geographical distribution areas, B. chinense and B. scorzonerifolium, were simulated by the maximum entropy(MaxEnt) model under current climate and two climate scenarios(RCP4.5 and RCP8.5) for the future(2050 and 2070), respectively. Meanwhile, the dominant environmental factors that restrict the distribution of these two species suitable geographical distribution areas were analyzed. The results show that(1) Precipitation of wettest period(Bio13) was the most important environmental factor affecting the suitable geographical distribution areas of B. chinense, followed by mean temperature of driest quarter(Bio09), and altitude(Elevation). In the same way, precipitation of wettest period(Bio13), temperature seasonality(Bio04), and altitude(Elevation) are the dominant environmental factors that affect the distribution of B. scorzonerifolium suitable geographical distribution areas.(2) Under the current climate conditions, the total area of suitable geographical distribution areas for B. chinense is 1.4755×10^(6)km^(2), which is account for about 15.37% of the total land area of China. And the middle and high suitable geographical distribution areas are mainly distributed in southern Shaanxi, eastern Shanxi, southeastern Gansu, central Shandong, central and western Hebei, etc. At the same time, the total area of suitable geographical distribution areas for B. scorzonerifolium is 1.8034×10^(6)km^(2), accounting for approximately 18.78% of the total land area of China, of which the middle and high suitable geographical distribution areas are mainly distributed in western and eastern Heilongjiang, central and northeastern Inner Mongolia, northern Hebei and central Shaanxi, etc.(3) Under the background of future climate change, the total suitable geographical distribution area of two species of Bupleurum both shows an increasing trend. In term of the migration study of suitable geographical distribution geometric center, the suitable geographical distribution geometric center of B. chinense will step by step move to the high latitude area in the northeast, while the suitable geographical distribution geometric center of B. scorzonerifolium will gradually migrate to the high altitude areas in the west.