不同放牧强度下门源草原毛虫在高寒草甸上的空间分布

Spatial Distribution of Gynaephora menyuanensis under Different Grazing Intensities in Alpine Meadow

按照放牧强度递增的顺序在高寒矮嵩草草甸上选取冬季自由放牧、轻牧、中牧、重牧4个样地,每个样地随机选取10个0.5m×0.5m的样方,对每个样方中的植被高度、盖度、虫口密度、毛虫的垂直分布高度等指标进行测定,根据空间分布指数对不同放牧强度下门源草原毛虫幼虫的空间分布情况进行分析。结果表明,适度的放牧干扰会增大门源草原毛虫的虫口密度,过度放牧则可抑制该物种密度的增大。门源草原毛虫在水平和垂直两个方向上均呈现聚集分布。放牧干扰不会改变该物种的聚集分布特征,但可通过对其食物及生境的作用,影响其聚集程度。

Winter pasture,under grazing,moderate grazing and heavy grazing pastures were used as study plots in increasing order of grazing intensity in alpine meadow.10quadrats（0.5m×0.5m）at each plot were randomly selected.The vegetation height,coverage and population density vertical distribution height of Gynaephora menyuanensis in every quadrat were measured.Then the spatial distribution of G.menyuanensis was analyzed under different grazing intensities according to the spatial pattern indexes.The results showed that moderate grazing would increase the population density of Gynaephora menyuanensis,but overgrazing inhibited the density increase.The distribution of Gynaephora menyuanensis were gathered on both horizontal and vertical directions.The grazing disturbance did not change the aggregate distribution characteristics of the species,but could influence its clustering intensity by affecting its food and habitat.