| Tea tree was originated in China with a long history. In recent decades, in order to gain higher and more steady yields of tea, the planting patterns were changed and the chemical fertilizers and insecticides were heavily applied, which inversely influenced the ecosystem of the tea plantation. As a result, the biodiversity indices declined and the dominant species of the diseases and insect pests of tea plants enhanced. Especially the insecticide residues in the tea, the resistance and resurgence of the pests have become more and more serious. So the sustainable ecological control of the tea pests has become more and more important and imminent for pollution-free tea.In order to understand the structure and dynamics of arthropod community and its mechanism of the community stability in the tea plantation, some mathematical models concerned were analyzed, improved and perfected by application of the theory of multivariate statistical analysis and the theory of grey system based on the mathematical ecology, finally the new mathematical models were further set up in this paper. The results were as follows.1. Structure and dynamics of the subcommunities in arthropod community were analyzed by the method of factor analysis (FA) based on the investigations in tea plantation. The results showed that the main species were smaller green leafhopper Empoasca vitis Gothe and mites in the pest subcommunity. E. vitis was positively correlated with Flatidae and other leafhoppers. Here, the correlation with another meansthat they had the same increase or decrease in population. The mites were mainly positively correlated with aphids and thrips. The main predators were spiders, Polyrhachis vicina Roger, ants and Mantidae in the predatory subcommunity and positively correlated with them. The main parasites were hymenopterous chalcids, Proctotrupoidea and Aphelinidae in the parasitic insect subcommunity. Chalcidoidea was positively correlated with Proctotrupoidea, and Aphelinidae was positively correlated with Braconidae. The main neutral insects were mosquitoes, flies in Diptere and Collembola in the neutral insect subcommunity. Mosquitoes were positively correlated with flies.2. According to the investigation in tea plantation, taking the feature indices dynamics of arthropod community and their subcommunities as the attribute, the factor analysis was conducted and the following results were obtained. (1) The abundance and dominance of the general arthropod community were positively correlated with those of the pest subcommunity. While there was no correlation between the predatory subcommunity and the neutral insect subcommunity, and the parasitic insect subcommunity was not significantly correlated with other subcommunities, being partial to the predatory. (2) The biodiversity, evenness and dominant concentration indices of the general community were positively correlated with the pest insect subcommunity and the predatory insect subcommunity, while there was no correlation between the parasitic insect subcommunity and the neutral insect subcommunity. In the whole community structure and dynamics were positively correlated with the pest subcommunity and the predatory subcommunity, follow with the parasitic insectsubcommunity, while was not significantly correlated with the neutral insect subcommunity.3. Based on the principal component analysis, the synthetic indices for community system evaluation were established and applied to the cluster analysis of the correlation between arthropod community and other subcommunities. The results were the same as those of factor analysis.4. The period was divided into 6 stages from October 17, 2002 to October 24, 2003 according to the synthetic indices of system evaluation for arthropod community in Fuzhou tea plantation (short for synthetic indices of community) by the optimal sorting method. The first stage was from the second ten days of October to the end of November. In this period, the arthropod species, individual in tea plantation were abundant. The speci...
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