【摘要】 了解红松的适宜区分布,对于红松种质资源保护和阔叶红松林的植被恢复具有重要意义。本研究利用R软件的ENMeval数据包,通过调整MaxEnt模型的参数(特征组合、调控倍率)来优化模型。基于优化后的MaxEnt模型,利用168个红松分布点数据和22个环境因子图层,模拟了红松的分布区域,并分析决定红松适宜区分布的主导环境因子及其阈值。结果表明,当特征组合为线性、二次型、片段化和乘积型,调控倍率为3时,模型复杂度和过拟合程度较低,模型模拟准确性提高,被确定为最终的设置参数。红松高度适宜区主要分布于我国东北地区东部山地,占研究区总面积的19.24%;低度适宜区和不适宜区分别占研究区的28.54%和52.22%。影响红松适宜区分布的主导环境因子主要是年降雨量、降雨量季节性变异系数、海拔和年平均温度,其适宜值范围分别是630～1090 mm、86%～97%、210～1140 m和0.3～4.3℃。更多还原

【Abstract】 Understanding the suitable habitat distribution of Korean pine( Pinus koraiensis) is significant for genetic resource conservation of Korean pine and vegetation restoration of broadleaved Korea pine mixed forest. In this study,we optimized the parameters( such as feature combination and regularization multiplier) of MaxEnt model. Using 168 geographical distribution records of Korean pine and 22 environmental factors,we simulated the habitat suitability of Korean pine and identified the major environmental factors controlling its distribution. The results showed that the complexity and degree of overfitting of the model were relatively low. The model was more accurate when the feature combination was linear,quadratic,hinge and product equation,and regularization multiplier was 3. Korean pine was mainly distributed in the eastern mountain area of Northeast China. The highly suitable area,low suitable area,and unsuitable area accounted for19.24%,28.54% and 52.22% of the total area,respectively. Annual precipitation,precipitation seasonality,elevation,and annual mean temperature played important roles in regulating the distribution of Korean pine,with the suitable threshold of each factor being 630-1090 mm,86%-97%,210-1140 m and 0.3-4.3 ℃,respectively.更多还原