沙冬青属植物在亚洲中部荒漠区的潜在地理分布及驱动因子分析

Potential Geographical Distribution of Genus Ammopiptanthus (Leguminosae) in the Eastern Central Asian Desert and Its Determinant Environmental Factors

在较大的空间尺度上,物种分布模型是预测物种潜在分布的有效途径之一。利用最大熵模型MAXENT,预测了蒙古沙冬青和新疆沙冬青在亚洲中部荒漠区的潜在分布;借助模型启发式搜索和多元线性回归分析揭示了控制其潜在分布的驱动因子。结果表明:①蒙古沙冬青的潜在适生区和实际分布范围基本一致,局限在阿拉善荒漠区的东部和南部、鄂尔多斯西部;最适生的分布区局限在内蒙古乌兰布和沙漠东缘和贺兰山北部的小部分区域。控制蒙古沙冬青潜在分布的关键因子主要是反映极端的温度和降水条件的因子,如最干月降水量、极端最低温和最冷季平均温度等。②新疆沙冬青最适生的潜在分布区局限在新疆乌恰县和沿昆仑山向南延伸的区域。反映极端气候和气候变化范围的因子,如温度季节性、最冷季平均温度、最湿月降水量和降水季节性等以及海拔,基本控制了新疆沙冬青的潜在分布。

On a large spatial scale, species distribution model is one of the effective ways for modelling species＇ potential distribution. Using species distribution model （MAXENT）, this study aimed to determine the potential distribution areas of Ammopiptanthus mongolicus and Ammopiptanthus nanus in the eastern Central Asian desert, and then to identify the determinant environmental variables contributing to the distri- bution. Results show that： （1） The produced potential distribution areas of A. mongolicus agree well with the observed ones, and species A. mongolicus are restricted distributed in the eastern and southern part of Alxa desert and the western Ordos of Inner Mongolia. The most suitable habitats are in the eastern edge of the Ulan Buh Desert and a small area of northern Helan Mountain. The distribution-influencing factors are mainly the extreme temperature and precipitation, for example, the most drought month precipitation, the extremely low temperature, the coldest season temperature, etc. （2） The most suitable habitats of A. na- nus are in the Wuqia County and south side along the Kunlun Mountains of Xinjiang. The influencing factors which control its potential distribution principally comprise of altitude and the extreme climatic factors.