摘要
河北平原长期抽取地下水进行灌溉导致地下水严重超采,引发了一系列环境问题,利用水价机制压采地下水。【目的】研究冬小麦适宜灌水量的水价方案。【方法】依据2007—2016年中国科学院栾城农业生态实验站冬小麦不同灌水次数和灌水量的长期灌溉试验资料,建立了作物产量对耗水和灌水的响应关系,研究了不同降水年型下最优灌水量和灌溉效益随水价的变化,确定了不同灌溉策略下的水价优化方案。【结果】与目前灌溉制度相比,当冬小麦生育期不灌溉时,平均减产达27%,枯水年产量降低近50%,水价的临界值是2.79元/m3,高于这个水价灌水收益为负,低于这个水价,灌水收益为正。为保证农民净收入不变,应平均每季补贴3 678元/hm2。当小麦季地下水消耗不超过100 mm时,平均水价应定为1.37元/m3,平均产量损失8.2%,应给予农民的补贴为2 556元/hm2。当地下水消耗不超过200 mm时,平均水价应定为0.38元/m3,产量平均损失1.3%,应给予农民的补贴为942元/hm2。【结论】宜采用水价加补贴回补方式鼓励农民采取节水灌溉。
【Objective】Winter wheat-maize rotation consumed a large amount of groundwater and has resulted in groundwater table dropping steadily, threatening sustainable agricultural production in north China Plain. Mitigation strategy has been taken by Hebei Province in attempts to reduce groundwater exploitation by increasing the price of water pumped for irrigation.【Method】We first established the dependence of yield on water consumption and the amount of irrigation based on the long-term irrigation experiment at Luancheng Agro-Experimental Station located at a piedmont of Taihang in Hebei Province. We then developed the relationship between optimal irrigation amount and its economic return under different annual rainfalls, from which we analyzed the optimal water price for different irrigation schedules. 【Result】 Compared with conventional irrigation, prohibiting groundwater extraction could reduce the winter wheat yield by an average 27%, and 51% in dry years. The threshold water price should be 2.79 yuan/m3 at which irrigation will not bring any economic befits to farmers;thus, on average, farmers should be subsidized 3 678 yuan/hm2 to compensate their loss from yield reduction caused by such a prohibition. If the farmers were allowed to pump 100 mm equivalence of groundwater for irrigation annually, the average yield loss is 8.25% and the threshold water price should be 1.34 yuan/m3; on average,therefore, farmers should be subsidized 2 556 yuan/hm2 for the lost yield. Similarly, if the groundwater allowance was increased to 200 mm, there would be no significant loss in yield and the threshold water price should be 0.38 yuan/m3; on average, famers should be subsidized 942 yuan/hm2.【Conclusion】We should encourage farmers to apply saving-water irrigation using water price added subsidies.
作者
闫宗正
房琴
路杨
梁硕硕
张喜英
YAN Zongzheng;FANG Qin;LU Yang;LIANG Shuoshuo;ZHANG Xiying(Key Laboratory of Agricultural Water Resources,Hebei Laboratory of Agricultural Water-saving,Center for Agricultural Resources Research,Institute of Genetics and Developmental Biology,Chinese Academy of Sciences,Shijiazhuang 050021,China;University of Chinese Academy of Sciences,Beijing 100049,China)
出处
《灌溉排水学报》
CSCD
北大核心
2018年第8期91-97,128,共8页
Journal of Irrigation and Drainage
基金
国家重点研发计划课题(2016YFC0401403)
河北省科技支撑计划课题(14227007D)
关键词
限水灌溉
水价
产量
经济收益
补贴
limited irrigation
water price
grain yield
economic profit
subsidies
