The Shrubbry Structure Character Of Vitex Negundo And Initiate Natural Management Pattern In The Watershed Of Miyun Reservior In Beijing

Used typical shrubbery plants of Vitex negundo var.heterophylla in the watershed of Miyun Reservoir in Beijing as this research object,by the research of age structure, distributive pattern of typical shrubbery plants of Vitex negundo var.heterophylla,with close-to-nature forestry theory and economic developing potential of Vitex negundo var.heterophylla,we discuss the high-efficient, stable and eco-economic structure pattern and manage pattern of Vitex negundo var.heterophylla theoretically to give full play to ecological benefit, economic benefit and social benefit of Vitex negundo var.heterophylla,answering the question of Country need ecology, Local need to develop,farmers need to increase income.The results show that the Vitex negundo var.heterophylla is dominant species in gully, sunny slope, half-sunny slope and half-shady slope, each importance value is 80.88, 56.40, 49.59 and 32.41, it means that Vitex negundo var.heterophylla holds an extremely important position in low mountainous region where water-heat condition is much poorer.Niche breadth value of Vitex negundo var.heterophylla in gully, sunny slope, half-sunny slope, half-shady slope is higher, which means Vitex negundo var.heterophylla has a high adaptive ability in this area. Seen from the natural secondary forest closed for reforestation, Vitex negundo var.heterophylla population belong to increasing type, with more young and less old individuals. If the existing natural secondary shrubbery plants is protected strictly and tended scientifically, the Vitex negundo var.heterophylla population can naturally recovered. Tested on the distributive pattern of Vitex negundo var.heterophylla population and those Vitex negundo var.heterophylla who have predominant habitats, it shows that Vitex negundo var.heterophylla population is contagious distribution, and reaches significant level by the test of Vitex negundo var.heterophylla population in the testing plot. Water and light are the main environmental factors affecting the development and distribution of Vitex negundo var.heterophylla population.Intimate natural management of Vitex negundo var.heterophylla population in the watershed of Miyun Reservoir in Beijing should insist on the principle of ecological feature, economy and feasibility, and also should insist on fully-using ecological function of Vitex negundo var.heterophylla, the ecological benefit of soil and water conservation, improving environment. The structure adjustment goal of Vitex negundo var.heterophylla is to achieve reasonable structure, high plant diversity and stable ecology. On the horizontal leve1, increasing plant types, diversity and evenness by the different stand condition and economic condition according to the principle of adaptation to local conditions. On the vertical level, establishing multilayer structure of combination of shrub and grass. Introduction of common and high ornamental value shrub species in Beijing will increase the biodiversity, community stability and tourism attraction, besides, it will increase the income of local residents.