| This article has been：Browse 2257Times Download 3044Times |
scan it! |
|
|
| DOI：10.13522/j.cnki.ggps.20180043 |
|
| Changing Water Price to Regulate Groundwater Extraction for Irrigating Winter Wheat in North China Plain |
|
YAN Zongzheng, FANG Qin, LU Yang, LIANG Shuoshuo, ZHANG Xiying
|
|
1. 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; 2. University of Chinese Academy of Sciences, Beijing 100049, China
|
| Abstract: |
| 【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. |
| Key words: limited irrigation; water price; grain yield; economic profit; subsidies |
|
|
