A Study On Higher Plants And Their Communities In Wetlands Around Dianchi Lake

Plateau wetland is a unique wetland type in the world, and its ecological service function is extremely important. But the plateau wetland ecosystem is fragile, which needs to strengthen the research and provides effective protection. The species, composition, distribution and change of wetland plant community is the result of long-term comprehensive function of many factors, and it not only reflects the evolution of wetland ecosystem and the development direction, but also instructions the comprehensive ecological effect of wetland. Therefore, the research on wetland plants and community vegetation of wetland ecological system have a great significance on the origin of vegetation, relationship between communities, utilization of plant resources and ecological restoration.This paper is based on the wetland plants and plant communities of wetlands around Dianchi Lake.26sampling points were selected around Dianchi Lake. The wetland plant community species composition, flora, plant ecological type, classification of community, community diversity and historical change of Dianchi lake area were researched through quadrat method and clustering analysis. The results were as follows:1.There were386kinds of higher plants around Dianchi Lake district. Among them there were8species of pteridophytes, which belonged to6genera in6families. There were6species of gymnosperms, which belonged to6genera in4families and372angiosperm species, belonged to271genera in92families. The main floristic composition were tropical components and temperate components, which respectively occupied43.1%and38.2%. But Chinese endemic species is scarce. There are47species of aquatic plants in the total species,118species of hydrophytes and221species of mesophyte. Among the386species of plants,152species were alien plants, including47invasive species.2. The plant community in the region can be classified into19types by clustering analysis and quadrat method. The typical local community type was few and advantage community was exotic plant community of artificial cultivation. In conclusion, aquatic plant community succeed from simple construction and single dominant specie communities to complex construction and none dominant specie communities. 3. Comparing with the species data recorded in the past half century,47species were disappeared, and22species were aquatic plants. And12plant community types were disappeared, which occupied63.2%of the original community types.11plant community types were newly recorded, but the dominant species of exotic plants occupied a half. And the distribution of vegetation in Dianchi Lake was decrease comparing with the past, the mainspring was the coverage area of submerged plant communities’ reduction.