Earlier Succession And Stability Of Artificial Vegetation Community On Disturbed Slope In Xiangjiaba Hydropower Station

The construction of large hydropower project is a kind of strong and profound activity to natural ecosystem, and to lead to regional ecological environment changing severely. Revegetation is an effective means of ecological compensation to terrestrial ecosystem in disturbed areas of hydropower project. For nearly a decade, the technique of revegetation on disturbed slope has made marked progress and the application scale has been increasing considerably. Nevertheless, the research about the constancy and stability of artificial vegetation community after rebuilding is still on an initial stage at present. This paper, Aiming at the slope of different disturbing types in Xiangjiaba hydropower station and taking artificial vegetation community as the research object, is to make studies of the process and stability of primary succession. The major researches methods are to set up fixed quadrates on the slope, carry out vegetation survey according to General Ecology, and then analyze the collected data of 5 years with the principles of Quantitative Ecology. This paper systematically clarifies the earlier succession’s dynamic characteristics and stability change of artificial vegetation community on disturbed slope, and the research results could supply theoretical support for revegetation on disturbed slope in hydropower, highway, railway and mine engineering.The major researches are as follows:Using the methods of TWINSPAN, the communities which are formed by 5 years’succession are classified. Based upon the classification, it is to choose 4 typical samples and study the succession process and stability of each community. The variations of communities’characteristics during the course of succession are studied by analyzing the indexes of species constituent,α-diversity,β-diversity and aboveground biomass. By analyzing the distribution pattern, niche breadth and overlap and interspecific association of the dominant species in different succession’s period, it is to study the relationship of competition and coexistence between initial species and invader species, and the effect of population characteristics on succession. According to laboratory experiments, it is to analyze the change of soil fertility indexes in different samples and to study the relationship between communities’ characteristics and soil fertility during the course of succession. Using DCA and improved M.Godron method, it is to study the succession syndynamics and stability of each plant community. Based on the research results, It suggests taking measures of revegetation projects on disturbed slope as followed:(1) according to different disturbance forms, to construct rational vegetation habitat on slope, (2) to select and constitute rational initial species, (3) to make advantage of local seed bank sufficiently, (4) to monitor the growth dynamics of artificial vegetation community and to execute appropriate ecological control.