我国粮食作物化肥施用技术效率的时空效应研究*——基于小麦、水稻的实证分析

SPATIAL CORRELATION AND TIME TREND EFFECT OF CHEMICAL FERTILIZERS′ TECHNICAL EFFICIENCY FOR CROPS IN CHINA

关键词:  化肥技术效率Moran′s I收敛性空间效应SFA

Key words:  chemical fertilizer  technical efficiency  Moran′s I  convergence  spatial effect  SFA

摘要:

［目的］分析我国粮食作物化肥施用技术效率的空间依赖性，并探讨其时间变化趋势。［方法］运用2004—2015年的面板数据和随机前沿分析法（SFA），计算小麦、水稻主产区的化肥施用技术效率，并运用空间Moran′s I指数和3种收敛模型对其进行了空间相关性和收敛性研究。［结果］（1）效率分析结果表明，小麦和水稻化肥施用的技术效率都处于较低的水平，分别为0529和0695，且都明显低于其生产的技术效率（小麦和水稻分别为0804和0950）。（2）空间效应方面，小麦和水稻的化肥施用技术效率都存在空间相关关系，小麦化肥施用技术效率的空间自相关程度要高于水稻，但随着时间的推移，水稻化肥施用技术效率的空间自相关程度逐渐增强，小麦则较为稳定。（3）时间效应方面，小麦、水稻化肥施用技术效率满足绝对β收敛，即省际间化肥施用的技术效率呈现出了不断趋同的现象。此外，通过进一步分析可以发现小麦、水稻化肥施用技术效率也满足条件β收敛，即各省化肥施用的技术效率会向该省所在区域的稳态水平趋同。［结论］我国农业生产过程中化肥施用的技术效率严重低下，但是不管在时间上还是空间上都呈现出了不断趋同的现象。为此，中央政府应在制度、政策上引导化肥合理施用提高化肥施用技术效率的同时也要积极推进区域间化肥施用技术效率的协调发展。

Abstract:

To analyze the spatial correlation and time trend of chemical fertilizer technical efficiency for wheat and rice, this paper calculates the chemical fertilizer technical efficiency by using the panel data from 2004 to 2015 and Stochastic Frontier Analysis method （SFA）, and then with the Moran′s I index and three convergence models to study the spatial correlation and time trend of chemical fertilizer technical efficiency for wheat and rice. The results were showed as follows. Firstly, the results of technical efficiency analysis showed that the chemical fertilizer technical efficiency of wheat and rice were at a low level with 0.529 and 0.695, respectively, and both were significantly lower than the production technical efficiency (the production technical efficiency for wheat and rice were 0.804 and 0.950, respectively). Secondly, in terms of spatial correlation, there is spatial correlation in chemical fertilizer technical efficiency for both wheat and rice. The spatial correlation degree of chemical fertilizer technical efficiency for wheat was higher than that of rice, over time the spatial correlation degree of chemical fertilizer technical efficiency for rice was getting higher and higher, but that of wheat was more stable. Thirdly, in terms of time trend effect, the chemical fertilizer technical efficiency for rice and wheat all met the absolute β convergence, that was, the chemical fertilizer technical efficiency of inter provincial showed a phenomenon of constant convergence. In addition, by further analyzing the condition β convergence, it could be found that the chemical fertilizer technical efficiency would converge towards the steady state level of the region of the province belonging. Finally, we can get the conclusion that the chemical fertilizer technical efficiency for wheat and rice in China are in a low level, and the chemical fertilizer technical efficiency for wheat and rice have a phenomenon of constant convergence in both time and spatial. Therefore, the government should guide the scientific application of chemical fertilizers through making some management systems and policies. While improving the technical efficiency of chemical fertilizer through technology, we should also actively promote the coordinated development of regional technical efficiency of chemical fertilizer.