沙地灌丛“虫岛”:概念、方法与模型构建

"Arthropod Island" of Shrub Effect:Concept,Method,and Model Construction

沙地灌丛与节肢动物间的作用关系可以用"虫岛"来表示,但是关于灌丛"虫岛"的概念、分析方法与模型构建,研究较少.通过定量化界定灌丛"虫岛"的概念与内涵,筛选计算灌丛"虫岛"的分析函数,旨在确立定量分析灌丛与节肢动物间作用关系的数学模式.结果表明,沙地灌丛"虫岛"是流沙生境中节肢动物群落和种群水平上在灌丛内外的统计性差异分布.种群水平上相对邻近影响指数RNE=(B-A)/max(A,B)与相对互相作用强度指数RII=(A-B)/(A+B)表达的内涵更为全面、准确(A,B分别表示灌丛内外平均量值),而在群落水平上5个指数均适用,但需实际情况检验.确立了群落和种群水平上灌丛与节肢动物间的定量作用模型:RII=α/(α+2B),α为灌丛对节肢动物的定量作用强度.

＂Arthropod Island＂ of shrub effect can be used to reflect the interaction between shrub and arthropods in mobile sand land.However,there was largely unknown about the concept,method,and model construction for the ＂Arthropod Island＂ of shrub effect.Through the quantitative concept for the ＂Arthropod Island＂ of shrub effect,the mathematical expression was selected in order to determine the model for the interaction between shrub and arthropods.The results were shown that ＂Arthropod Island＂ referred to the statistical distribution of arthropods at community and population levels between the microhabitats beneath the shrub canopy and in the open spaces.Relative neighbor effect（RNE） and relative interaction intensity（RII） was confirmed to be better expressions to indicate the quantitative ＂Arthropod Island＂ at the population level.At the community level,these five indices could be used but needed to be test in light of the results.Mathematical model for the interaction between shrub and arthropods was expressed as RII=α/（α＋2B）（α means the interaction intensity） at both community and population levels.