白羊草灌丛草地种群生态位的研究

运用以Shannon-Wieren指数为基础的生态位宽度计测公式和Pianka的生态位重叠计测公式,在土壤水分、土壤pH值、土壤全氮含量3个资源维上研究白羊草灌丛草地主要植物种群生态位宽度和生态位重叠关系。建群种白羊草的平均生态位最高,为0．905;达乌里胡枝子的生态位宽度仅次于白羊草。表明白羊草、达乌里胡枝子具有最强的耐受北方寒冷干燥及家畜放牧利用的能力。白羊草在3个资源维上同其他种群的生态住重叠值都较高,表明其在群落中具有较强的占据资源优势能力。因此,在对退化白羊草灌丛草地植被恢复时,白羊草和达乌里胡枝子是首选草种。

Study on the Niche of Population in Bothriochloa Ischaemum Shrub Grassland

The niche breadth and niche overlap of main populations on the gradients of soil water, soil pH value, and soil total nitrogen content were measured with the formulas described by Shannon-Wiener and Pianka. The average niche breadth of B. ischaemum, which was better than other species, was 0.905. Lespedeza dahurica had the second average niche breadth. These indicated that B. ischaemum and L. dahurica had the. highest capability to endure coht, dry climate of north and be defoliated by animals. The higher niche overlap with other species on three resource dimensions showed that B. ischaemum had strong competed superiority. B. ischaemum and L. dahurica will be the first selected species when the B. ischaemum shrub grassland should be improved.