Research On Ecological Degeneration And Restoration Of Baiyangdian Wetland

Wetland, which provides us with resources of water, biology, energy, transportation and traveling, is one of the most productive ecosystems on the earth. Its physic, chemic and biologic constituents interact, enabled wetland to have giant environmental functions and ecological benefits in many aspects that cannot be substituted for by others ecosystems, such as adjusting climate, self-controlling water source, storing floodwater for use in the future, avoiding drought, purifying water quality, protecting biodiversity. Therefore wetland together with forest and sea is called the most three biggest ecosystems on the earth. So it is main protect object of our human beings.Baiyangdian wetland, situated in the half arid region of the Plain of North China where water is scarcity, is the biggest natural lake in North China. It is in the middle reaches of Daqing River, nine rivers inpour into it. Baiyangdian plays important roles in slowing flood, storing water, adjusting climate, protecting biodiversity and maintaining the water body's purifying capacity as well as vegetating fish and reed, developing eco-tourism.Since 1960s, Baiyangdian faced many ecological crises: being short of fountain, decreasing of water quality, reducing of biodiversity, etc. The ecosystem is degenerating, which in turn, leads to the weakening of its ecological functions.This article took the ecology theory as the instruction, using the ecological principles into the appraisal of Baiyangdian wetland's ecosystem features, the ecology process and the ecological environmental function. Based on the analysis of Baiyangdian's main ecological environmental problems and the degenerated reasons, the thesis took emphasis on wetland's hydrology characteristic, its change and the ecological influence. Then using ecology restoration principle, explored the ecological restoration approaches from the following aspects: restore wetland's habitat, bio-diversity, ecosystem structure and function, scientific management and moderate development and so on, aiming at providing scientific instruction for the Baiyangdian wetland ecosystem's healthy development and maintenance its ecological function persistently.The result indicated that: First, hydrological character is the determinative factor of constituting and maintaining wetland's unique structure, process and functions. During the recent half century, the wetland hydrological characteristic have seen great changes owning to vegetation destruction in the upstream, interdiction of waterreservoir, unreasonable utilization, and natural drought. The main embodiments are: reducing in the amount of inputting water, degrading of water level, increasing of evaporation, drying up of shallow lake, etc. Second, hydrological characteristic changes directly or indirectly lead to a series of ecological environmental problems such as decreasing of water quality, reducing of the amount and species of water biotic resources and deterioration of ecological function. Baiyangdian is withering to swamp. Third, ecological restoration approaches: restore water amount by means of ascertaining reasonable water level, strengthening distribution and management of water resources in the drainage area, uniting water reservoir and lake, supplying water from water reservoir in the arid time, investing water form South to North Water Transfer Project, etc. Restoring water quality via concentrated disposal of sewage, wetland disposal, marking off environmental protective district, salving float grass and making into foodstuff, multi-utilizing waste, fathering self-pollution, etc. Through virescence and cleaning silt restore wetland fondues. Protect ting wetland biology through renewing and reestablishing water biology, changing the traditional piscatorial production mode, establishing ward center for birds and protecting wild animals. Converting farmland back to wetland, withdrawing degenerated areas, establishing natural reserve, optimizing and deploying wetland structure and function. Making off ecological environmental functional d...