基于技术效率及影子价格的农业灌溉弹性需水研究——以黑龙江省为例

The Flexible Demand Analysis of Agricultural Irrigation Water Use Based on Technical Efficiency and Shadow Price: Taking Heilongjiang Province for an Example

基于黑龙江省13个地市2000~2015年的农业投入和产出数据,采用随机非参数包络分析法（Sto NED）,估算黑龙江省农业灌溉用水的技术效率和影子价格,提出了基于技术效率和影子价格的农业灌溉用水弹性需求分析模型,研究表明：在相同的产出条件下,2015年农业灌溉用水技术效率无效比2000年降低了23.68%、农业灌溉用水技术效率有效提高了25.02%;哈尔滨市的农业灌溉用水技术效率最高,达到了0.978 8;齐齐哈尔市的农业灌溉用水技术效率最低,为0.685 4;黑龙江省农业灌溉用水影子价格平均值在2.04~3.86元/m3之间波动,各地市农业灌溉用水影子价格平均值波动性较大,其极差达到了11.92元/m3;当其他投入保持不变的条件下,黑龙江省农业灌溉用水价格、农业总产出和农业用水技术效率每增加1%,农业灌溉用水量将分别减少4.64%、增加1.10%和减少0.20%。

Based on the input-output datas of agriculture in 13 cities of Heilongjiang Province from 2000 to2015, the input-output index system was built. The input indexes included cultivated area of the crops, total power of agricultural machinery, fertilizer amount, the number of agricultural employment and water consumption for agricultural irrigation and the output indexes included agricultural output value. Then the method of stochastic nonparametric envelopment of data was introduced to build the technical efficiency model of agricultural irrigation water. Based on the measurement results, the shadow price of agricultural irrigation water was calculated with the shadow price theory. Last the empirical model of flexible demand analysis on agricultural irrigation water was established using the Shephard theory. On the basis of the above analysis, the model bulit in this paper can estimate the noise in the data of the agricultural irrigation water sample correctly and formulate the economic relations between the agricultural irrigation water and the agricultural production adopting the crop production function reasonably. Compared with 2000, in the condition of the same output, the agricultural water use inefficienint in 2015 decreased by 23.68% and the agricultural water use efficienint increased by 25.02%. The most agricultural water use efficienint of all cities in Heilongjiang Province is Harbin with0.978 8, the least is Qiqihar with 0.685 4. The average agricultural water shadow prices of Heilongjiang Province are between 2.04-3.86 yuan/m3. But the average agricultural water shadow prices of different cities differ largely, and the range is 11.92 yuan/m3. On the condition of other inputs no change, the agricultural water consumption will decrease by 4.64%, increase by 1.10% and decrease by 0.20% respectively with each increase of1% of agricultural water price, total agricultural output and agricultural water efficiency. Due to the shortcomings of relying on the functional form of SFA（Stochastic frontier analysis） model and ignoring the data stochastic noise of DEA（Data envelopment analysis） model, the Sto NED model can better solve these problems and satisfy the the concepts and principles of SFA and DEA. The empirical model for the analysis of agricultural irrigation water elasticity demand can effectively reveal the impact mechanism of the agricultural irrigation water price and the technical efficiency to the agricultural irrigation water demand in Heilongjiang Province.The research results have important theoretical and practical significance for drawing up the agricultural water use price scientific and rational, promoting the reform of agricultural water use price and saving agricultural water resources in Heilongjiang Province.