SPATIAL DISTRIBUTION OF MASSON PINE CATERPI LLAR PUPAE ANDITS PARASITIC NATURAL ENEMY GUILDS FOR THE OVERWINTERING GENERATION IN THE DIFFERENTPINE FORESTS
不同松林马尾松毛虫蛹及其寄生天敌群子的空间格局分析

Studies on the spatial construction and distribution of masson pine caterpillar (Dendrolimus punctatus (Walker)) pupae and its parasitic natural enemy guilds for the overwintering generation in three pine forests (i.e., the pure masson pine stands of high and the low damage level, and the Pinus elliottii P.massoniana P.taeda mixed pine forest) were carried out using geostatistics. The results of analysis reveal spatial distributions of pupae and its parasitic natural enemy guilds semivariograms. The semivariogram of pupae was described by spherical model in the mixed pine forest, indicating an aggregated spatial arrangement. In the pure masson pine stands of high damage, semivariogram of pupae was fitted by an exponential model, also indicating an aggregated spatial arrangement. In the low damage stands. semivariogram was linear with 0.423 intercept and a very low slope (0.003814), indicating random or uniform spatial pattern. The semivariograms of parasitic natural emenies guilds in three pine forests were linear with little slope, showing random or uniform distribution. The results and methods are applicable to the temporal and spatial dynamics of insect population and the insect pest ecological control.