The Impact Of Urban Environment On The Population Exchange Between Sparrow And Seasonal Proliferation Genes

With the accelerating process of urbanization, natural landscape in the city is gradually replaced by buildings and residential areas, wild animal habitat environment is gradually deteriorated. Compare with the natural environment, dense urban road network is one of the important features of the urban environment. Lots of road in the city is widely distributed in various types of landscape, its density and traffic volume is increasing, especially in the areas with a rapid speed of economic development. While road plays a important role in human activities, it also takes many direct or indirect negative effects for ecological processes. A number of studies have found that road has isolation effect on wildlife population diffusion, however, it is unclear about whether road has effect on the diffusion of the wild animals which have the ability to fly, such as birds. In order to research if the urban environment has effect on birds diffusion, this thesis take tree sparrow (Passer montanus) as the case species, using eight microsatellite DNA molecular marker, analyzed the genetic diversity of17sparrow populations from urban and outskirts areas of Beijing. Analyzed the correlation of population genetic differences with four factors, include geographical distance, age of roads, the number of highway and main road. And search the sparrow’s seasonal diffusion behavior.Firstly, each population has a high level of gene polymorphism, expected heterozygosity and allelic richness. Gene flow of the sparrow populations has a high level, and hereditary difference of the sparrow populations has a low level. Mantel test found that there is no significant correlation between the four factors (the number of highway, the number of main road, highway age and the geographic distance) with Fst values. AMOVA analysis results show that82.33%of the gene variation from individual,17.21%of the gene variation from individuals within population, only0.46%of the gene variation among populations. These results show that urban highway not has a severe effect on the gene flow between sparrow populations.Secondly, urban populations have eight locus deviate Hardy-Weinberg balance and suburban populations have five locus deviate Hardy-Weinberg balance. In addition, the Mantel test indicates that the significance level of correlation between the number of highway and Fst value was0.097, is close to the0.05significance level. And, there have18among91Fst values reach the0.05significance level. All pairings that have significance level are on the opposite side of highway, and the pairings on the same side has no significance. There is none Fst value of suburban population pairing has significance level. Above results show that urban highway have a weak effect on the sparrow diffusion.Thirdly, the hereditary difference analysis of3urban sample points and1suburban sample point in summer and winter show that all genetic polymorphism of the sparrow populations in the summer are higher than winter. Indicate that the sparrow breeding group is composed of many small populations. The summer and winter sparrow populations of Jinyuan and Minzu University of China have a larger hereditary difference, however the gene composition of sparrow population in summer and winter of Yuyuantan and Beilangzhong village is relatively stable. Above results show that the seasonal diffusion of city sparrow population is larger and the sparrow population in suburban and urban park have a stable composition in different seasons, seasonal spread range is relatively small.