Studies On Wetland Plant Diversity Protection In Beijing

Based on a comprehensive survey for the wetland vegetations in Beijing, the community structures, types of community and the composition and distribution of species in wetland plant communities were studied. Systemic analysis of wetland plant diversity and important value of species were conducted in this paper. The impacts of xerophytes invasion on natural vegetation and the rule of succession in wetland plant communities in Hansiqiao wetland nature reserve and Yeyahu wetland nature reserve were discussed. In this paper, we also made a clear description for the wetland plants protection status in Beijing. The major threats to the protection of wetland plant diversity in Beijing were discussed, and some sμggestions were made in order to protect the wetland plant diversity and wetland resources.1. The number of species in wetlands in Beijing is very abundant, and the community diversity is fairly high. Totally, 208 plant species were found in 475 plots that surveyed, within which 95% were herbs. In those areas that have a high level of hydrology condition, like the upper reach of Yongdinghe river, hansiqiao reserve and Yeyahu reserve, the growth of wetland plants are very good, while in areas where the hydrology condition is poor, the proportion of xerophytes in a community increase a lot, the wetland vegetation shows a tendency of degradation, from wetland vegetation to dryland vegetation. Wetland habitat conditions are retrogressing. All these have made it clear that water resources condition is the most important factor that controls the compositions and the growing patterns of wetland plants in wetland communities. Also, the lack of water resources is the biggest threat to wetland plant diversity protection.2. In Beijing wetlands, original wetland plants as Phragmites communis, Typha angustifolia often have a high degree of important value, above 10 usually, and may even higher than 50. These original plants usually are edificato of wetland vegetation. It is crucial to protect those plants, so as to protect all the wetland plants as a whole. Because of droμght problem, the wetland plant communities are under a converse succession, from original wetland plant communities to xerophytes communities. The invasion of Humulus scandens and other xerophytes, and the disturbance of human activities, have caused the decreasing of plant diversities and the degeneration of vegetations in wetlands in Beijing. These problems exerted seriously impacts on the play of ecological function of wetlands, and greatly reduced their ecological value and landscaping value.3. Except for water content in soils is the most important factor that impact the composition and diversity of wetland plants, water quality plays an important part in the controlling of wetland plants composition and their growing status. Water eutrophication in wetlands had caused the notorious growth of submergent aquatic plants, as Potamogeton crispus, Myriophyllum spicatum, and Potamogeton...