基于改进TOPSIS方法的耕地系统安全评价及障碍因子诊断

耕地系统安全评价及障碍因子诊断是改善耕地安全状况、促进耕地可持续利用的基础。论文在界定耕地数量、质量、生态安全关系的基础上,从耕地数量、质量、生态“三位一体”的系统角度出发,构建耕地系统安全指标体系,运用改进的TOPSIS模型和障碍度模型,以江西省鹰潭市为研究区域,研究2005—2015年耕地系统安全时空变化状况及进行障碍因子诊断。结果表明：1）2005—2015年间,鹰潭市耕地数量安全和耕地质量安全均整体呈上升趋势,耕地生态安全呈先上升后缓慢下降趋势,耕地系统安全水平整体呈上升趋势,2015年,安全状态耕地提升至90.44%,非常安全耕地占2%;2）不同县（市、区）因发展类型及特点不同,耕地系统安全变化特征不一,月湖区耕地系统安全水平最低并呈先下降后缓慢上升趋势,余江县耕地系统安全整体较高并呈上升趋势,贵溪市耕地系统安全处中上水平并呈先下降后上升趋势;3）土壤有机质含量、化肥负荷、耕地保有力度、pH、固定资产投资、灌溉保证率、人均耕地面积、城市化水平、环保投资占GDP比例和农药负荷是制约耕地系统安全的主要障碍因子。

Evaluation and Obstacle Factor Diagnosis of Cultivated Land System Security in Yingtan City Based on the Improved TOPSIS Method

Evaluation and obstacle factor diagnosis of cultivated land system security are significant foundation for improving the security of cultivated land system and promoting the sustainable use of cultivated land. This paper takes Yingtan City as the example area. According to the systemic thinking and “triad of quantity, quality, ecology of cultivated land”, this article selects 38 factors that reflect quantitative security, qualitative security and ecological security of cultivated land to build the evaluation index system based on the concepts of quantitative security, qualitative security and ecological security of cultivated land and the relationships between them. Then, the temporal and spatial variations of cultivated land system security during 2005-2015 are evaluated and the obstacle factors are diagnosed by using the improved TOPSIS method and disorder degree model. The results showed that: 1) During 2005-2015, the quantitative security and qualitative security of cultivated land showed an increasing trend, and the cultivated land ecological security presented a rising tendency during the first five years while it had a slow downward trend in the following five years. Generally, the cultivated land security was uptrend. In 2015, the area of cultivated land in safe state occupied 90.44% of the total cultivated land area, and the area of cultivated land in very safe state area accounted for 2%. 2) Different counties have different development types and characteristics, while the variation characteristics of cultivated land system security were different in different counties due to the different development types and the characteristics of counties. In the Yuehu District, the cultivated land system security was the lowest, and it declined first and then rose slowly. The cultivated land system security in Yujiang County was in a higher level, and it showed an increasing trend. The cultivated land system security in Guixi County was above the average, and it went down first and then went up. 3) The main obstacle factors that affected the security of the cultivated land system in Yingtan City were soil organic matter content, fertilizer load per unit area, arable land protection capacity, pH, fixed assets investment, irrigation assurance, the area of cultivated land per capita, the level of urbanization, the proportion of environmental protection investment in GDP, and pesticides load per unit area.