面源污染减排增汇措施下的农业生态经济系统耦合状态分析--以三峡库区忠县为例

三峡库区是国家生态环境建设重点治理区,实现农业经济发展和控制农业面源污染是该区域当前面临的两大难题。为明确库区面源污染减排增汇政策与措施下的农业生态经济系统耦合态势,以三峡库区典型面源污染治理区的忠县为例,利用生态农业发展和面源污染治理相关方面的数据,构建结构方程模型,考察三峡库区忠县农业面源污染减排增汇政策与措施背景下的农业资源利用、农业发展与农业生态经济耦合系统中各要素的相互关系与作用路径。通过设定面源污染减排增汇政策与措施、农业资源利用、农业发展、耦合状态的4个潜变量及其所对应的观测变量,根据对研究区农业生态经济系统耦合关系的感性认识,提出了6个基本假设,在此基础上设计农业生态经济系统耦合关系模型。实证结果表明:农业面源污染减排增汇措施与农业资源利用之间具有相互影响的关系,其路径系数为0.79,说明政府的农业面源污染减排增汇措施促进了农业资源的合理利用;农业面源污染减排增汇措施与农业发展之间具有相互影响的关系,其路径系数为0.80,说明面源污染的减排措施与政策对农业发展具有较强的激励作用;农业发展与农业资源利用具有相互影响的关系,其路径系数为0.77,说明农业经济的发展建立在农业资源合理利用的基础上;农业面源污染减排增汇措施对农业生态经济系统耦合态势具有正向作用,路径系数为0.85,说明研究区面源污染减排措施对耦合态势具有明显改善作用;农业资源利用和农业发展对农业生态经济系统耦合态势具有正向作用且作用较大,其路径系数分别为0.91和0.89,说明农业产业与农业资源系统的耦合符合其本质的运行规律发展。综合考虑上述潜变量之间的结构关系,发现农业面源污染减排增汇下的农业资源与农业经济发展成为影响系统耦合的关键,这是理解系统耦合的一个有效视角。

Coupling state of agricultural eco-economic system under emission mitigation and sink enhancement of non-point source pollution--A case study of Zhong County in the Three Gorges Reservoir Region

The Three Gorges Reservoir Area is a key control region of eco-environmental construction in China. However, how to achieve agro-economic development and control agricultural non-point source pollution in the region have emerged as difficult issues in recent years. To verify the coupling process of agricultural eco-economic system under emission mitigation and sink enhancement, data from the Zhong County (a typical non-point source pollution control district in the Three Gorges Reservoir Area) was used to develop eco-agriculture and non-point source pollution control. Then an equation-driven model of the construction structure was studied in terms of the interrelationship and interaction paths of the various elements of agricultural resources, agricultural development and agricultrual eco-economic coupling system in the Three Gorges Reservoir Aarea of Zhong County under the backdrop of emission mitigation and sink enhancement of non-point source pollution policies and measures. The paper put forward 6 basic assumptions based on 4 latent variables (emission mitigation and sink enhancement of non-point source pollution policies and measures, agricultural resources, agricultural development and coupling degree of agricultural eco-economic system) and the corresponding observation variables. Based on these elements, the paper designed a coupling model of the agricultural eco-economic system. The empirical results revealed that the path coefficient of the interrelationship between agricultural non-point source pollution control measures and agricultural resources utilization was 0.79. This suggested that the government's emission mitigation and sink enhancement measures promoted rational utilization of agricultural resources in the region. The path coefficient of the interactive relationship between emission mitigation and sink enhancement measures of agricultrual non-point source pollution and agricultural development was 0.80. This also suggested that the measures and policies were strong incentive for agricultural development in the study area. The path coefficient of the relationship between agricultural development and resources utilization was 0.77, indicating that agro-economic development in the region was based on reasonable agricultural resources utilization. Emission mitigation and sink enhancement measures positively influenced the coupling process of agricultural eco-economic system. The path coefficient was 0.85, which suggested that the measures in the study area significantly improved the coupling process. The utilization of agricultural resources and development positively influenced the process of agricultural eco-economic system coupling. The respective path coefficients were 0.91 and 0.89, indicating that the coupling process of agro-industry and agro-resources system conformed to the nature of agricultural development. Considering the structural relationship between the latent variables, it was noted that under background of non-point source pollution emmission mitigation and sink enhancement measures, agriculturla resources and economic development were the key elements of system coupling. The elements formed an effective perspective for understanding the coupling process of the system.