草原毛虫对高寒嵩草草甸植物群落结构及土壤特性的影响

Effects of Grassland Caterpillars on the Plant Community Structure of Alpine Kobresia Meadows and Soil Properties

[目的]研究不同危害级别的草原毛虫与高寒嵩草草甸的群落结构特征和土壤特性的关系。[方法]选取10个20m×20m样地,在每个样地内随机量出5个5m×5m的样地,每个样地设置6个0.25m×0.25m的小样方。对其生物量,植被高度,生草层厚度,裸地面积,土壤含水量,植被总盖度等进行测定,并且用Excel2003和SPSS13.0软件进行统计分析。[结果]不同草原毛虫危害级别与高寒嵩草草甸的植物群落结构特征和土壤特性具有显著差异(P<0.05)。[结论]随着虫口密度的增加,高寒嵩草草甸群落结构逐渐由莎草科为主演的草地更替为杂类草草地。

[Objective] To study the relationship between the grassland caterpillars at different Hazard levels and the structure of alpine Kobresia meadow or soil properties. [Methods] A total of ten plots （20 m × 20 m） were chosen. In each plot five 5 m × 5 m little plots were randomly selected and six 0.25 m × 0.25 m sample plots were then selected in each little plot. The biomass,vegetation height,grass-layer thickness,bare land area,soil moisture and total vegetation cover were determined. Data were collected by Excel 2003 and statistically analyzed by SPSS 13.0 software. [Result] The results were showed that there was a significant difference （P0.05） between the grassland caterpillars at different Hazard levels and the structure of alpine Kobresia meadow or soil feature. [Conclusion] With the increase of grassland caterpillar density,the plant community structure of alpine Kobresia meadows change from sedge family-dominant community to the forbs-dominant community.