基于熵权法的南县土地生态安全评价

Ecological Security Evaluation of Land in Nan County Based on Entropy

基于PSR模型,从压力、状态和响应3方面构建南县土地生态安全评价指标体系,利用熵权法分析2009—2013年南县土地生态安全状况.评价结果表明,总体而言,2009—2013年南县土地生态安全水平呈逐年恶化趋势,由临界安全等级降为不安全等级;就子系统而言,压力子系统土地生态安全水平虽呈波动式上升趋势,但仍处于非常不安全等级,状态和响应子系统都呈波动式下降趋势,由不安全等级降为非常不安全等级;影响土地生态安全的主要子系统为响应子系统,其中城市化率、单位播种耕地粮食产量、单位耕地化肥使用量、水土协调度、第三产业比重、环保投资占GDP比重、工业废水达标排放率等为主要因素指标.

The system of evaluating ecological security of land in terms of pressure,state,and response is constructed based on PSR model.Then the entropy is used to evaluate the ecological security of land in Nan county from 2009 to 2013.The results show that the land ecological security in this county deteriorated from middle insecure to insecure.As for each subsystem,the pressure showed a gradual upward trend,but it still remained insecure;the state system and response system were all on a declining trend from insecure state to very insecure state.The main sub-system that influences the land ecological security is response.The influential factors include urbanization,grain output,application of chemical fertilizer,soil and water conservation,the proportion of the tertiary industry,investment in environmental protection,and industrial wastewater emission.