关键词: 蚊类, 生态位, 生态位重叠指数, 无倾向对应分析排序, 干旱区湿地

Abstract:

Objective To determine the niche breadth, overlap, and inter-species correlations of mosquito species in five arid wetlands in North Xinjiang using ecological niche theory and relevant methods. Methods Mosquitoes were captured with carbon dioxide-baited light traps and were then classified and counted. Niche breadth and overlap were estimated with Shannon-Wiener's and Pianka's formulae, respectively. Hierarchical cluster analysis was performed with a matrix of the constituent ratio of individual species, and detrended correspondence analysis (DCA) was performed with the population size of each mosquito species in different wetland habitats. Results A total of 20 731 mosquitoes, belonging to 16 species in 5 genera, were captured in the five arid wetlands in North Xinjiang. Of these, Aedes dorsalis had the greatest niche breadth (0.8326), followed by Ae. vexans (0.6350), Ae. caspius (0.5954), and Anopheles messeae (0.5558). Regarding niche overlap index, there were 26 species (20.31%) with log-transformed values above 0.90 and 85 species (70.83%) with log-transformed values above 0.50. The five wetland habitats were classified into two major ecotypes by hierarchical cluster analysis. DCA ordination diagram showed the longest distance of Ae. sinkiangensis and Mansonia richiardii from other species among the mosquitoes tested. Conclusion The dominant mosquito species does not always has the greatest niche breadth. Similar mosquito population structure exists in the wetlands of Buergen River, the lower reach of Ertix River, and the lower reach of Yili River, as well as in the wetlands of Ebinur Lake and the estuary of Emin River. Species distribution of mosquitoes and their correlations with wetland habitats can be directly reflected by DCA ordination.

Key words: Mosquito, Ecological niche, Niche overlap, Detrended correspondence analysis ordination, Arid wetland