Koraiensis Broad-leaved Forests In Insect Ecosystem Health

Changbai Mountain is the tallest peak of the northern temperate zone of our country, and keep the typical model, complete forest ecosystem system. Especially in the north slope, the broad- Leaved wood of red pine , the animal( insect), plant( tall tree, shrub, herb)and the tree grows plentiful. The living creature is numerous, and the complete vegetative chain of formation is with the food net, provided the proper and living space for the animal( insect)and plant( tall tree, shrub, herb).The research object of this paper is the broad- Leaved wood of red pine in north slope of Changbai Mountain .By analyzing the composition , construction, biodiversity and season diversity of forest community , we probed the rule of the forest community changing with the season and the ecological effect of forest insect community affected by forest plant community, appraised firstly regulating ability of forest ecosystem on forest pest and estimated finally effect of forest insect on ecosystem health. The research result is following:The annual species richness index of studied forest plant community averaged 64.688, the species diversity index was 2.982 .The proportion of every functional group of forest plant community is: Herbaceous layer( average is 68.89%)> tall tree layer( average is 15.266%)> shrub layer.( average is 15.845%)The proportion of every functional group in forest insect communities is remarkably different, and the order of the proportion is herbivorous insect group(average 0.729) > predatory natural enemy insect group(average 0.136)> parasitical insect group(average 0.135).With seasonal change, the proportion of herbivorous and predatory insect group decreased obviously, while that of parasitical insect group increased on average by 147%.Annual species richness index of forest plant community showed a negative relation with that of herbivorous and parasitical insect community, namely S plan, =75.872-0.129* Sz+1.407* Sb-2.925 SjjAnnual species diversity index of forest plant community showed a closely positive relation with that of predatory and parasitical insect community, namely H plant =3.491-0.355* Hz+0.190* Hb+0.252 Hj.Annual species even index of forest plant community showed a positive relation with that of parasitical insect community, a negative relation with that of herbivorous insect community, namelyE P;ant =0.621-0.401* Ez-0.0427* Eb+0.574* Ej, and little relation with predatory insect community.There was significant correlation between forest plant community and forest insect community, namely constituting complexity of forest plant community had large influence on diversification of insect species composition.With diversity of forest plant community medium, forest community had best control on forest insect. So we could connect composition and diversification of forest plant community with ecosystem function of biodiversityæ¢'ontrolling on forest insect. Therefore, in theory and practice, controlling ability of forest community on pest could be inferred from diversity of forest plant community .Furthermore, forest community could be transformed and rebuilt from the relation of communities of plant and insect, so that diversification will be more rationalized, controlling ability of forest on pest will be increased and forest health will be realized.