华北平原节水技术、灌溉用水量反弹效应与地区异质性——基于Malmquist和LMDI指数分析

很多地区节水技术的应用并未带来农业灌溉用水总量的下降。通过应用中国华北平原地级（直辖）市2000—2018年的面板数据,采用Malmquist指数和LMDI指数进行分解,测算出节水技术带来的农业灌溉用水反弹量和预期农业节水量。结果表明：中国华北平原节水技术引起的农业灌溉用水反弹效应均值为15.02%,这表明华北平原整体并未完全达到节水技术应用带来的预期农业节水量。节水技术应用放松了水资源约束,农户会扩大灌溉面积或高耗水高收益作物的种植,从而削弱节水技术的节水效果。黄河区的农业节水反弹效应程度最大,部分地区甚至会造成农业灌溉用水的增加。节水灌溉面积的增加是农业节水反弹效应的直接原因,农田灌溉水利建设投资的增加和水权市场建设的不完善则是根本原因。

Water-saving technology,rebound effect of irrigation water consumption and regional heterogeneity in North China Plain: Based on Malmquist and LMDI Index analysis

The application of water-saving technology is an important measure to save agricultural water resources. However, agricultural irrigation water consumption in many areas has not decreased with the application of such technology. By applying the panel data of 52 cities at prefecture level or above in China's main grain producing areas from 2000 to 2018, and using Malmquist index and LMDI index, we calculated the rebound amount of agricultural irrigation water brought by water-saving technology and the expected agricultural water-saving consumption. The results of the study show that the average rebound effect of irrigation water consumption in the North China Plain was 15.02% during the study period, which means that the North China Plain has not fully achieved the expected result brought by the application of water-saving technology. The application of technology relaxes the constraints of water resources. Farmers will expand the irrigated area or increase planting of high-water-consumption and high-yield crops. The effect of water-saving technology is weakened. There are different rebound degrees of irrigation water consumption in the Yellow River, Huaihe River and Haihe River basins. The average value of the overall rebound effect in the Yellow River is 41.39%, and the degree of the rebound effect is the greatest, while the overall rebound effect in the Huaihe River is the least. From the perspective of administrative region, the rebound effect of agricultural irrigation water was mainly found in Shandong, Henan and Hebei provinces. The overall average value of the rebound effect in Henan Province is 49.89%, followed by Shandong Province (29.98%), and Hebei Province (23.89%). The increase in water-saving irrigation area is the direct cause for the rebound effect of agricultural water-saving. The increase in investment in farmland irrigation water conservancy construction and the imperfect construction of water rights market are the root causes. The regional heterogeneity of rebound effect is caused by the differences in the application level of water-saving technology and the construction of water rights trading system. However, this heterogeneity will be gradually eliminated with the increase of investment in farmland irrigation conservancy construction and the improvement of water rights trading system. The research conclusion is of great significance for the adjustment of water-saving technology and irrigation policy in the North China Plain.