小陇山国家自然保护区毛栗群落生态位及空间分布格局研究

Study on Niche and Spatial Distribution Pattern of Castanea mollissima Community in Xiaolongshan National Nature Reserve

在野外调查的基础上,对小陇山国家自然保护区内毛栗(Castanea mollissima Bl.)群落中主要种群的Shannon-Wiener多样性指数及Levins生态位宽度、生态位重叠及空间分布格局各项指标进行了分析。结果表明,毛栗的生态位宽度最大,为0.81,枫杨(Pterocarya stenoptera C.DC.)的生态位宽度值最小,为0.50;毛栗与其他种的生态位重叠值在0.33~0.72。毛栗的生态位重叠值比较大,群落中由于利用相同资源位而产生的竞争相对较大。6个样地中毛栗群落的分布格局均表现为聚集分布,样地3中的毛栗群落聚集强度最低,样地4中的毛栗群落聚集强度最高。

On the basis of field investigation, the index of Shannon-Wiener diversity indicators and Levins niche breadth and niche overlap and spatial distribution pattern of the dominant populations in Castanea mollissima Bl. community in Xiaolong-shan National Nature Reserve were analyzed. The results showed that the widest niche width of C. mollissima was 0.81, while the niche breadth of Pterocarya stenoptera C.DC. was the smallest （0.50）; The ecological niche overlap of C. mollissima and other species was 0.33 to 0.72. The niche overlap value of C. mollissima community was relatively high, and the competition is relatively large due to the use of same resources. The six samples of C. mollissima communities all showed aggregated dis-tribution pattern; the aggregation intensity of sample 3 C. mollissima community was the lowest, while of sample 4 was the highest.