Lα──m模型在检验昆虫种群空间分布型与抽样调查中的应用

Application of Lα──m Model in the Testing of Spatial Pattern for Insect Population

根据随机分布中方差（ｖ）与均值（ｍ）相等的性质，提出了一个新的种群聚集度指标，即Ｌα指标。Ｌα不仅可用来判断昆虫的空间分布型，而且在许多情况下，Ｌα与ｍ之间存在着显著的线性关系，据此建立了Ｌα──ｍ模型（Ｌα＝θ＋ηｍ）。当Ｌα──ｍ线性相关显著时，θ和η的不同组合型式就揭示了种群不同的空间分布型的信息，同时可将θ和η的估计值具体地应用于抽样调查之中。

Based on the character that varivance(v)is equal to mean(m)in Poisson distribution, a new aggregation index is presented in this paper,i.e La index(La=m-m/v +1).The index he can not only be used for testing insects population spatial pattern,but also represent the relationship between La and m,according to the property of La and m,the linear regression formula is presented,that is Lα-m model(La=θ+ηm).When the L-mis linear'the estimated parameter values of θ andηan offer different information con-cerning the spatial pattern of insect population. On the basis of the Lα-mmodel,a set of math formula for insects population sampling technique was derived.