Assessment Of Ecological Security Of Poyang Lake Wetland Based On PSR Model

Wetlands are one of the three valuable ecosystems on the earth and are known as “Kidney of the earth”, which possess ecological service functions including regional micro-climate improvement, water conservation, environment purification, habitats for biodiversity, etc. Nowadays, under the impact of human activities, wetlands are confronted with harsh circumstances, for instance, shrinkage of wetland area, degeneration of wetland functions, and reduction of biodiversity, which have become a hotspot of scientific research. Poyang Lake wetland is the global important ecotype designated by World Wildlife Fund, and joined the world catalogue of important wetlands, which plays a significant ecological function in the world. However, Poyang Lake Wetland are also facing with the negative effects of the reclamation, dyke construction, sand mining, etc. And the ecological security of wetland is threatened. In the view of this situation, it is vital to carry on relevant study of the ecological security of Poyang Lake wetland.Based on the theory of regional ecological security research, the PSR(Press-Situation-Response) model were adopt to establish evaluation index system of ecological security in Poyang Lake, integration of RS and GIS technology methods were utilized, Poyang Lake wetland in 2010 was taken as a case study which ecological security were evaluated and analyzed. This study aimed at exploring the formation mechanism of the spatial distribution of ecological security level, and proposing the corresponding protection measures based on cause, specific contents are displayed as follows: Through literature review, expert interviews and field research, this study analyzed the impact factors of ecological security of Poyang Lake wetland. according to index selection principles, discriminated the elements and selected evaluation index and clarified the logical relationship among different indexes, this study based on the PSR(Pressure- Situation- Response) model to construct the evaluation index system of ecological security of Poyang Lake wetland; AHP method was used to build indexes of judgment matrix, entropy-weight-model was applied to calculate weight of each index element; index data were collected, the indexes were processed using RS and GIS technology in accordance with index calculation methods, all indexes were quantified and spatialized; multi-source spatial data of indexes were fused, According to the formula of aggregative index of regional ecological security, this study calculated and produced the patterns graph of spatial distribution of the Poyang Lake wetland eco-security aggregative index, the causes were analyzed and corresponding measures were suggested.Research results indicated that:(1) the ensemble ecological security level of Poyang Lake wetland is under the condition of basic security, in which ecological security index of core region in Poyang Lake wetland is relative high, it attain basic security and comparative security grade and the ecological status of regional wetland is relatively optimistic;(2) the behavior of sand mining lead to quite pressure on ecological security of the research region, which is primary factors of ecological environment deterioration;(3) climate changes effects normal exertion of wetland ecological function;(4) more sparsely-population conducive to maintain wetland harmony relationship between people and natural;(5) nature reserve play a significant role in maintaining ecological security;(6) on account of the low economic level, less inputs of science and environmental protection is harmful to ecological protection. Direct at these problems, relevant solutions are proposed, such as development of eco-agriculture, restrictions or a ban on sand mining, increase support on reserves in Poyang Lake.The results presented that based on the rational construction of evaluation index system, application of RS and GIS technology, this study can sufficiently demonstrate the spatial distribution of regional ecological security, and the evaluation conclusions and recommended measures target for more special characteristics, which provide scientific basic and support for monitoring of regional eco-environment and decision-making of ecological protection.