Ecosystem Health Assessment And Analysis Of Bearing Capacity In Liaohe Estuary Wetland

Supported by the project "National major projects of water pollution control andmanagement science and technology-rivers theme of comprehensive treatment technologyintegration and project demonstration of liaohe river water pollution", and explicated the topic of“the wetland ecosystem health appraisal”, this paper has a systemic research and discussionabout theory, method, and practice of the wetland ecosystem heath appraisal. It explains theconcept and performance foundation of wetland ecosystem health, taking liaohe estuery as anexample, using related scientific theory such as the ecological system, landscape ecology andtheory of wetland ecosystem health as directions, constructed assessment indicator system of thewetland ecosystem health from aspects of composition, structure, function and the service ofecosystem and so on. The whole assessment indictor system consists of structural characteristicsof wetlands, functional characteristics of wetlands and the human social environment, including30indictors. Furthermore, damage degrees tested with scores by assignment and APH weightsgiven to each indicator to assess wetland ecosystem health. Refering to international standards ofwetland ecosystem health, protective plans of liaohe esturey and natural reserve plan ofshuangtaizi estury, liaohe ecosystem health is divided into four degrees. As result shows, liaoheecosystem is5.34, belonging to Third Degree, is in the sub-health state. It is also shown thatliaohe estury has a relatively complete ecological structure and certain vitality. However, facedwith great external pressure and is close to ecological threshold.Using ecosystem health appraisal, combined with regional characteristics of environmentalimpacts, under the guidance of sustainable development theory, ecological bearing capacitytheory and ecology theory, built a suitable indicator system of regional environment and resourcebearing capacity. And according to econometric model of surplus rate of the established system,the surplus rate of liaohe estuary is-0.0687,6.87%overloaded, and in line with the results ofecosystem health assessment. The surplus rate above, analyzes the dynamic change trend ofresources and environment in liaohe estuary, is importance of sustainable development.