Research On Watershed Ecosystem Health Assessment In Taizi River

Watershed ecological deterioration has been an important eco-environmental problem,which is a major bottleneck of threatening the human survival and restricting the economicdevelopment. It is very important to maintain watershed eco-health. Liaohe River Basin isone of China’s seven major watersheds, which is the region of industrial and agriculturalproduction base and energy base. Under the pressure of economic development model, waterpollution has been getting more serious than ever before, which is threatening living anddevelopment of human beings and eco-health. Taizi River is one of the most importanttributary of water system of Liaohe River Basin, flowing westward through Benxi, Liaoyangand Anshan three large heavy industrial cities. As a result, Taizi River is a region with mosttypical eco-health degradation, and the region with water pollution serious results fromhuman activities. In this dissertation, Taizi River Basin was selected as a study case. Suchcontents were discussed: the characteristics of watershed ecosystem and environmentalproblems identification, the status of watershed eco-health of Taizi River analysis, theprimary stress factors of watershed eco-health impairment of Taizi River and drivingmechanism analysis. What studied in this dissertation was important to guide the watershedecological comprehensive management and protection.Based on the theories and methods of landscape ecology, watershed ecology andecosystem health assessment, this paper studied the landscape characteristics, regular rules ofchanges and ecological problems firstly. Then, constructed the basic framework of watershedeco-health assessment, set up the integrated model and established the grading system.Finally, Taizi River Basin was cited as an example in the research on watershed eco-healthassessment. In order to identify the impact scopes and degrees of human activities on thewatershed eco-system, to determine the priority protection objects and management targetswithin the watershed.The main conclusions drawn in this dissertation include:(1) The temporal and spatial pattern of landscape and the characteristics ofeco-environment analysisThis paper summarized the natural situation, social economic situation and thecharacteristics of water environment. Multi-phase and multi-resolution remote sensing datawere selected to extract landscape elements in Taizi River Basin. Landscape index andtransformation matrix were used to analyze the landscape the temporal and spatial pattern andregular rules of changes. (2) Watershed eco-health assessment method analysisThis paper took maintenance of watershed ecological integrity and service function asthe main line. Based on the theoretical foundation of the principle of landscape ecology,watershed ecology and ecosystem health, according to the components of watershedecosystem and ecological process of “riparian zone as a filter belt intercepts terrestrialpollution sources to reduce pollutants into the water” within watershed, watershed ecosystemwas divided into aquatic, riparian and terrestrial areas as the evaluation objects. Combinedwith the characteristics of the ecological environment of Taizi River Basin, the basicframework of watershed eco-health assessment was constructed. Analytic hierarchy processwas adopted to set up the integrated model for health assessment on watershed ecosystem andestablished the grading system.(3) Results of case assessment analysisThis dissertation evaluated the condition of ecosystem health of Taizi River Basin in2010. The research indicated that comprehensive index for eco-health of Taizi River Basin is2.24, with a fair level of eco-health condition. The area of the region with poor level ofeco-health condition is significantly larger than the area of the region with good level. Inview of spatial distribution: The status of eco-health in Taizi River Basin has verticaldistribution which from upstream to downstream presented degradation trends, the plain areaof northwestern watershed stays at the lowest level. In addition, according to ecologicalcondition comparison of typical evaluation units of Taizi River Basin, this paper discussedthe infection of watershed eco-health. Water environment pollution seriously caused bydevelopment activities such as over population, industrial city construction and agriculturalproduction are frequent change pattern of land use is the primary intimidation factors fecosystem health impairment of Taizi River Basin.