依据农户调查数据,运用结构方程模型分析了安塞县及其南、中、北商品型生态农业系统耦合关系,结果表明:农业资源与农业产业是商品型生态农业系统耦合的核心,但由于生态环境改善未对系统耦合起到基础或支撑作用,使得资源与产业局部相悖。从安塞县整体而言,生态环境直接影响系统耦合,但其标准化系数却是-0.11,导致农业资源与产业态势标准化相关系数只有0.46,使系统耦合对经济效益的影响强度较弱,即退耕还林还草工程的实施改善了生态环境,但环境改善所增加的农业资源量并未得到相关产业的有效利用,系统耦合效果不显著;就安塞县南-中-北而言,其商品型生态农业系统耦合模式类型分别为"林区养殖业-果业-设施农业"、"经济林-果业-设施农业"和"畜牧业-特色农产品-经济林",由于养殖业与林草资源未形成有效产业链,相比较北部耦合效果较好。针对农业资源利用率低的现实,在商品型生态农业建设过程中需要强化草畜业,发展优质果业及精、细、密型种植业,完善商品型生态农业系统链网结构,实现农业产业与资源的优化耦合。
To investigate possible differences in the coupling relationship of EASC (ecological agro-system of commodities) due to location, the coupling relationship of EASC in Ansai county and its south, north, and central section based on data from household surveys was analyzed using the structural equation model. Results showed that agricultural practices and agricultural resources were the core of the coupling relationship of EASC. When agricultural resources were utilized with low efficiency, agricultural practices did not advance in the same speed with environmental amelioration and agricultural resources accumulation, which hampered the optimization of the coupling relationship of EASC and also the advance of the regional economy. At the county scale, the ecological environment had direct impacts on the system coupling, but the standardized estimate was -0.11, which caused the standardized estimate between agricultural resources and agricultural practices was only 0.46, weakening the efficiency of the system coupling on economic benefits. Although agricultural resources for the environment increased by enforcing the Grain for Green Project, the effect of the coupling relationship of EASC was insignificant, resulting from the agricultural resources not being utilized efficiently. In south, north, and central Ansai county, the coupling models of EASC were "stockbreeding - fruit tree planting - installment agriculture", "grazing - special agricultural product - production forest" and "production forest - fruit tree planting - installment agriculture" accordingly. Differences in the coupling model of EASC, induced by the location differences, made the characteristics of the coupling relationships distinct in each region of Ansai county. As there was not an effective and efficient production chain between livestock breeding and vegetation resources in south and central Ansai county, the coupling effect of EASC in north Ansai county was better. Since the agricultural resources were not used efficiently, c