Study On Community Diversity And Seasonal Dynamics Of Garden Wetland Insect In Wuhan City

China has extensive wetland. Garden wetland, or called wetland landscape architecture as a unique type of artificial wetland which exist in urban ecosystem, has close relationship with human. Wuhan city has hundreds of lakes and abundant wetland landscape. But in recent years, hygrophytes are found seriously deteriorated by insects and the harmful species are increasing due to the continuous introduction and cultivation to urban wetland of hygrophytes. The damages have large negative influence on the aesthetic enjoyment and utilization of hygrophytes and wetland landscape. Because of the lack of systematic study on insect community of garden wetland landscape, scientific research of entomology diversity and community structure of wetland landscape architecture in Wuhan city were projected to provide basic proof for pest management, and for further protection and harmonious development of garden wetland landscape.Data were collected in 9 locations from 2008 to 2009. Systematic investigations were primarily based on Jiefang Park(JF) and Yuehu Park(YH). Totally 11,494 samples classified under 14 orders,105. families and 307 species were collected in 9 sites including general and systematic investigation.In the study on insect community structure and seasonal dynamic of garden wetland,7,131 individuals got from systematic investigations in Jiefang Park and Yuehu Park, were consisted of 198 species belonging to 13 orders, 82 families. Diptera, Hymenoptera, Lepidoptera, Coleoptera, Homoptera and Hemiptera species occupied more than 80% of total families. It's the same when counted in species. The number of individuals of the orders mentioned above had nearly 90% of the whole samples. In both two parks, Diptera species was the major group, the propotion.of families were 25.76%(JF) and 22.54%(YH) respectively, the propotion of species were 18.18% (JF) and 15.49%(YH) respectively. While Hymenoptera species ranked second, which accounted for 18.18%(JF) and 15.49%(YH) of total families. However, considering the whole number of species, Lepidoptera species ranked second, which accounted for 20.44%(JF) and 18.44%(YH). The results of dominative insects in different months showed that besides the harmful insects such as Hyaloptera amygdali Blanchard, Galerucella grisescens (Joannis) and Apoderus sp. became the dominative insects, natural enemy such as Leis axyridis (Pallas) and flower-visiting insects such as Zizeeria karsandra also could be the dominant species in some periods. Compare on the order stage, dominative insects appeared in turn, first one was Diptera, then Homoptera, Coleoptera, Lepidoptera, the last one was Hemiptera. Statistics analysis indicated that the trend of the changes with month in the diversity index(H'), evermess index(J) and dominant concentration index(C). When the month progressed, indexes were increasing. September had the highest diversity index in both Jiefang(4.7949) and Yuehu(4.4611) Park. The significant analysis of insect community structrue parameter between Jiefang and Yuehu Park, which showed there was no significant differences between the two parks, The conclusion can explain the relationship between plant or environment and insect, in another word, similar plant structure may lead to identical insect community.September was the month with the highest diversity index, which insect community included 11 orders found the whole year except Thysanoptera and Corrodentia. The insect functional group of September were made of four parts, such as phytophagous (herbivore), parasitic, saprophage and other. The trophic structure was integrated. Among the food web, phytophagous insect was the primary group.Lythrum salicaria Linn., as the main plant in the two parks, was the crucial habitat of the garden wetland insect. There were 50% of the total specimens from L. Linn. The data described most samples were found on the chief vegetation. According to the Seasonal dynamic of the insect community diversity of L. Linn. in two parks, September was the month with the highest Shannon-Weiner index too. The figure of diversity indexes were 4.1102 (Jiefang Park) and 3.8552 (Yuehu Park). Correlation analysis showed that diverstiy indexes of L. Linn. in two parks were all significantly negative, neither on 0.05 nor 0.01 level. The results of this part were vegetation types had impact on insect community.Comparsion of constructed wetlands and natural wetlands, the conclusion was that the former one had much more entomological resource than the latter. Urban wetlands had small area, but held abundant entomological resource in store. Garden wetlands should be received much more attention to ensure a better development.