基于三阶段SBM模型的中国农业生态效率研究

目的]剔除外生环境影响和随机干扰对农业生态效率的影响,更精准测度中国各地农业生态效率,为中国绿色农业发展提供有效建议。方法]文章基于考虑非期望产出的SBM模型结合三阶段DEA建模法构建考虑非期望产出的三阶段SBM模型,利用2008—2017年中国31省(市、自治区)面板数据,在剔除外生环境影响和随机干扰的基础上对中国各地农业生态效率进行了测度。结果]外生环境影响和随机干扰对农业生态效率测度有着明显影响,在外生环境影响和随机干扰下2008—2017年中国31省市农业生态效率均值皆有明显下降,因此使用三阶段SBM模型是必要的;宏观经济环境改善会增加农业生态效率冗余,政策支持力度的加大和科技发展能减少农业生态效率冗余;整体来看,中国农业生态效率不断改善,第三阶段中国31省市农业生态效率均值从2008年的0.37增长到2017年的0.59,但未达到效率前沿,仍具有改进空间,其中,农业生态效率领先省(市、自治区)与落后省(市、自治区)之间差距较大,第三阶段农业生态效率均值最高的广东省比最低的西藏自治区高出0.85。结论]为了提高农业生态效率促进绿色农业发展一方面需要营造良好外部环境,重视科技创新作用;另一方面要多角度推动农业环境改善,促进地区交流合作。

A STUDY ON CHINA'S AGRICULTURAL ECOLOGICAL EFFICIENCY BASED ON THE THIRD STAGE SBM MODEL

This research aims to eliminate the impact of exogenous environmental impact and random interference on agricultural ecological efficiency, more accurately measure the agricultural ecological efficiency of China''s provinces and cities, and provide effective suggestions for the development of green agriculture in China. Based on the SBM model considering unexpected output and Three-stage DEA modeling method, a three-stage SBM model considering unexpected output was constructed. Using panel data from 31 provinces and cities in China from 2008 to 2017, the paper measured the agricultural ecological efficiency of China''s provinces and cities on the basis of excluding the exogenous environmental impacts and random disturbances. The influence of exogenous environment and random disturbance had significant effects on the measurement of agricultural ecological efficiency. Under the influence of exogenous environment and random disturbance, the average agricultural eco efficiency of 31 provinces in China decreased from 0.56 to 0.46 from 2007 to 2018, so it was necessary to use the three-stage SBM model. The improvement of macroeconomic environment would increase the redundancy of agricultural ecological efficiency, and the increase of policy support and the development of science and technology could reduce the redundancy of agricultural ecological efficiency. Overall, China''s agricultural ecological efficiency had continued to improve. The average agricultural ecological efficiency of China''s 31 provinces and cities had increased from 0.37 in 2008 to 0.46 in 2017, but it had not reached the frontier of efficiency and there is still room for improvement. Among them, there was a large gap between the leading provinces and the backward provinces in agricultural ecological efficiency. In the third stage, the average value of agricultural ecological efficiency in the highest provinces was 0.85 higher than that in the lowest provinces. In order to improve the agricultural ecological efficiency and promote the development of green agriculture, on the one hand, it is necessary to create a good external environment and attach importance to the role of scientific and technological innovation; on the other hand, it is necessary to promote the improvement of agricultural environment from multiple angles and promote regional exchanges and cooperation.