The Structure Dynamic And Nich Of Land Insect Community In Zhalong Wetland

Insect community in zhalong wetland was researched in this paper, including community structure, dynamic sequential character of space-time, diversity and so on. Moreover, the relationship among each group was discussed in zhalong wetland.(1) The present study collected samples of nocturnal insects, and sample locations included Zhalong village, Yantongtun, Tumutai and Yuweichang. The results are as follows:A total of 139 species belonging to 54 families in 14 orders were identified, of which Lepidoptera, Coleoptera and Dipteral are the major orders. The insect communities of the Zhalong wetland have been analyzed, by using the curve of the insect community species-abundance, the indices of diversity, the connection of the evenness and the indices of diversity. The results reveal that the species rank abundance of insect of the Zhalong wetland fits a lognormal model. The species richness (S) of four different locations were Zhalong village>Yantongtun> Yuweichang> Tumutai. However, the evenness (J) and diversity index (H) were Yantongtun>Zhalong village>Tu mu tai>Yuweichang. The relationship of Shannon-wiener diversity index (H'), Pielou evenness (J') and species richness index (S) were used to analyze the community diversity in different regions. In Yantongtun, the diversity index (H') of the insect community was significantly correlated with the evenness index (J') and the richness index (S). The diversity index (H') was significantly correlated with the evenness index (J),but not with the richness index (S) in Zhalong village and Yuweichang. In Tumutai, the diversity index (H') was not significantly correlated with the evenness index (J') and richness index (S). Different interference from human activities affact structure and dynamics of insect community in Zhalong wetland(2) In order to study the influences of the different succession stages of Zhalong wetland habitat on insect species diversity under water disturbance, the systematic investigation of insects were conducted in eight types of habitats (the lake habitat, Reed marshes, Korshinky reed marshes, Korshinky marshes, Korshinky-wet meadows, Wet meadows, Miscellaneous meadow, Grassland meadow)in zhalong wetland. The results showed that a total of 5822 insects were collected, belonging to 11 Orders and 58 Families and 143 Species. Among them, orthoptera, dipteral and Odonata were advantage taxa. The species richness of insects was higher in Grassland meadow than other ones. The Shannon-Weiner diversity index and the evenness index of insect community were higher in the lake habitat, and the lowest in wet meadows. The results of clustering analysis and principal component analysis showed that the similarity of insect community in different habitats were relevant with water interference strength and vegetation types, and the species and individual numbers of predatory taxa had important regulation effects on insect community stability. The Insect community stability analysis showed that insect community at the lake habitat was the strongest, and wet meadows was the weakest. The results suggest that the water disturbance influenced the environment where insect community survived, and then influenced the species composition and quantity distribution.(3) The niche and competition among species of insect community in different habitats in zhalong wetland were studied. The results showed that there were obvious niche overlaps and competitions in different species which used the same resources. Space niche breadth values of main groups were similar, the same as time niche breadth values.niche similarity coefficient of insect community indicates that the difference between each group is not big. Spider groups are important regulator of zhalong wetland insect ecological system. But Orthoptera and Coleoptera,Odonata group space niche overlaps were no significant, Spider groups mainly effect orthoptera hardly effect others groups of predatory, research indicates that some measures should be implemented at habitat and period of larger number of orthoptera individual, so the relationship of insect group balance better now.