Evaluation of land eco-security in Wanjiang district base on entropy weight and matter element model

Focusing on the problems of method disunity, information shield and subjectivity of the evaluation of land eco-security in China, this paper evaluated land eco-security of Ma’anshan, Hefei, Wuhu, Xuancheng, Anqing, Chuzhou, Chizhou, Chaohu and Tongling nine cities in Wanjiang district with the theory of entropy weight and matter element model, and the results were compared with that by comprehensive evaluation method. The entropy weight method includes following steps: building system of assessing factors, setting up field of the factors for classifying eco-security, constructing model of entropy and matter element analysis, calculating relevancy between the factor and land eco-security, making out the weight of every factors. The result showed that the land eco-security of Ma’anshan was more dangerous, followed by Chizhou, Anqing. Xuancheng, Hefei and Chuzhou were safe. The grade of Wuhu, Chaohu and Tongling were of a safer trend, which was consistent with the result of comprehensive assessment. The main factors of land eco-security in Wanjiang district included pesticide capacity per-unit area, amount of SO2 per GDP, water resource capacity per capita, density of people, forest coverage ratio, proportion of arable land area over 25 slope, and ratio of worked exhaust gas and so on. The information of comprehensive quality can be obtained by method of comprehensive assessment, while by method of matter element model, the discrete information of single factor and the steady status can be described in addition to the comprehensive quality. Therefore, matter-element model is valuable in land eco-security assessment.