基于共同前沿SBM模型的农业用水效率测度及改善潜力

为了实现农业水资源可持续利用和保障国家粮食安全，地区必须提高农业用水效率。基于共同前沿下的非期望产出SBM模型，对中国31个省市1998~2015年农业用水效率进行了测算，在综合考虑各地农业资源承载力、环境容量、生态类型和发展基础等因素的基础上，将中国各地区进行分组，分别考虑了各组区域下农业用水效率的差异性、变动趋势以及改善潜力。结果表明：共同前沿下，各组农业用水效率值从高到低排列依次为保护发展区、优先发展区和适度发展区，其多年均值分别为0.623，0.568和0.432。这表明，如果采用潜在的最优生产技术，三大区域将分别平均有37.7%、43.2%和56.8%的效率提升空间，改善潜力巨大。管理无效和技术无效是导致地区农业用水效率损失的两大来源，优先发展区效率损失主要是由管理无效造成，完善管理制度和提高管理运营水平是促进农业用水效率改善的重要策略，保护发展区和适度发展区效率损失的原因则具有多样性，管理无效和技术无效二者皆有，因此需要结合技术和管理双角度来设计效率改善策略。

Analysis of Agricultural Water Efficiency Measurement and Improvement Potential Based on Meta Frontier SBM Model

In order to achieve the sustainability of agricultural water resource and assure national food security, it is imperative to improve the regional agricultural water efficiency(AWE). In this study, we measure the AWE of 31 Chinese provinces(municipalities, autonomous regions) for the years 1998 to 2015 based on SBM model which considers both undesirable outputs and metafrontier technology simultaneously. Subsequently, taking the factors such as the bearing capacity of agricultural resources, environmental capacity, ecological type and development foundation into account, we divide the sample into three groups: prioritized development zone, moderate development zone, protected development zone. Then the regional differences, evolution trend and improvement potential are empirical studied, respectively. The results showed that the average values of AWE with reference to metafrontier of protected development zone, prioritized development zone and moderate development zone are 0.632, 0.568 and 0.432. The finding showed that if the potential optimal production technology was adopted, the three major regions would have a large room for efficiency improvement of 37.7%, 43.2% and 56.8%, respectively, indicating the potential for improvement would be huge. Technology and management ineffectiveness were the two major sources of regional AWE loss. The efficiency loss of the prioritized development area is mainly caused by the ineffective management, showing that improving both the management system and the management level are of significance strategies to promote the regional AWE. The loss of efficiencies in protected development zone and moderate development zone are mainly resulted from the low level of agricultural water production technology and the ineffective management. Thus, it was necessary to combine the technical and management improvement strategy to improve the efficiency.