斑须蝽种群空间分布格局Weibull分布的拟合

Weibull分布的概率密度函数为f(x) =(c/b) (x -a) /b]c -1exp (x a) /b]c ,x≥a。本文首次用于拟合班须蝽三代卵块的空间分布 ,8批抽样数据拟合结果表明班须蝽三代卵块在烟田的空间分布遵循Weibull分布。从而丰富了班须蝽种群空间格局的分布理论。同时 ,利用斑须蝽种群空间格局的资料探讨了Weibull分布的参数b、c与种群密度及种群聚集度之间的关系 ,结果表明 ,尺度参数b与种群密度、种群聚集度间均分别存在极显著的线性相关关系 ,形状参数c与种群密度存在极显著的正幂函数相关关系 ,与种群聚集度之间存在极显著负幂函数关系。

Simulating of Weibull Distribution with Spatial Distribution Pattern of Dolycoris baccarum(L.) Population

Probability density funcation of Weibull distribution is expressed as f(x)=(c/b)(x-a)/b] c-1 exp (x a)/b] c,x≥a. The paper, for the fist time, uses the model to simulate spatial distribution of Dolycoris baccarum(L.) population. 8 batches of sample data have been used to simulate and the results show that the spatial distribution of Dolycoris baccarum(L.) population agrees with Weibull distribution. This research enrich the spatial distribution theory of Dolycoris baccarum(L.) population. Also the ecological meaning of the parameters, b(scale parameter) & c(shape parameter), of the weibull distrbution were approached based on case analysis with 8 batches of sample data of Dolycoris baccarum(L.), and it concludes that: the scale parameter b and population density is dependent in positive linear correlation, the b and aggregation degree of populatin A(A=Variance/Mean) is dependent in negative linear correlation, the shape parameter c and population density is dependent in positive power function correlation, the c and aggregation degree of population is dependent in negative power function correlation.