山西南部脱皮榆种群生态位的研究

在山西省脱皮榆分布比较集中的霍山设置 4个样地 ,中条山设置 3个样地 ,采用样方法对脱皮榆种群进行调查 ,共作 5 85个样方 .将土壤含水量、土壤有机质含量和土壤全氮含量分别作为反映脱皮榆生长环境的资源轴 ,选择该区 2 2种灌木 ,5 3种草本 ,计测其在 3条资源轴上的资源选择性系数 L 、生态位宽度 B 、脱皮榆与其下灌木的生态位重叠 O .结果表明 :脱皮榆在 3条资源轴上生态位宽度值大小为 :B w >B n >B o ,其资源选择性系数则相反 ;连翘、3裂绣线菊在生态适应上与脱皮榆具有一致性 ;与脱皮榆生态位重叠值较大的连翘、虎榛子等是脱皮榆种群不同的生态种组 ;用土壤含水量、土壤有机质含量和土壤全氮含量作为资源轴研究脱皮榆种群生态位宽度和生态位重叠是可行的

Study on niche of population of Ulmus lamellosa in the south area of Shanxi province

The distributing center of Ulmus lamellosa on Huo mountain was set as four stands ,and Zhongtiao mountain was selected to set three stands. 585 plots were investigated by sampling method. Water, organic matter and nitrogen were used as the resource axis to reflect the growing environment of Ulmus lamellosa , 22 shrub species and 53 herbaceous species were selected to calculate the patchness index(L), niche breadth(B) and niche overlap(O) among Ulmus lamellosa , shrubs and herbaceous. The results show that the order of niche breadth of Ulmus lamellosa in the three resource axis is B(w)>B(n)>B(o), while the patchness index(L) is on the contrary; Forsythia suspensa, Spiraea trilobata are in accord with Ulmus lamellosa on the ecological adaptation ; The niche overlaps between Forsythia suspensa , Ostryopsis davidiana and Ulmus lamellosa are larger , Forsythia suspensa and Spiraea trilobata are regarded as the vary ecological groups.It is feasible to use the water, organic and nitrogen as resource axis to study niche breadth and niche overlap of Ulmus lamellosa .