| 摘要: |
| 【目的】在粮食生产与水资源支撑能力高度矛盾的河北省太行山山前平原,定量探讨冬小麦生育期“春浇一水”限水灌溉模式可否实现浅层地下水采补平衡。【方法】应用改进的SWAT模型对灌溉量相异的八种情景进行模拟,并基于8个指标对不同灌溉方案的压采与节水效应进行定量评估,在此基础上针对浅层地下水位止降回升这一约束条件,以冬小麦减产最小为目标,结合0-1规划,在22个子流域对灌溉方案进行优选。【结果】①冬小麦“春浇一水”方案能使得研究区的浅层地下水位下降速度平均减缓至0.34 m/a以内,并可将现状的浅层地下水井灌超采量平均削减70%以上,但这将以冬小麦平均减产大约25%~40%为代价。②在空间分布上,位于研究区北部的大清河淀西平原具有相对较好的地下水涵养效果,而在南部的子牙河平原,冬小麦产量相对更高。③优化后“春浇一水”模式的具体区划为：在保定地区的大部分县(市)域,主要推荐实施灌溉定额为50 mm 的方案；在邢台和邯郸地区,主要推荐实施灌溉定额为40 mm 的方案；在石家庄地区的西南部,主要推荐实施灌溉定额为30 mm 的方案。【结论】在研究区内大约70%的面积上可通过实施“春浇一水”方案实现浅层地下水采补平衡,本文可为这个浅层地下水严重超采的井灌区为压采而实施冬小麦“春浇一水”限水灌溉模式提供定量化的科学支撑和差异化的推荐方案。 |
| 关键词: 限水灌溉;浅层地下水;采补平衡;作物产量;SWAT模型;优化 |
| DOI： |
| 分类号:S274.3；S512 |
| 基金项目:国家自然科学基金(41807183) |
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| Could the limited irrigation scheme for winter wheat with once time at the jointing stage achieve shallow groundwater equilibrium?-- A simulation of Taihang Mountain piedmont plain in Hebei Province |
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ZHANG Xueliang, DING Beibei
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China Agricultural University
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| Abstract: |
| 【Objective】In the piedmont plain of Mount Taihang in Hebei Province, a well-irrigated region that is facing a dilemma between water resources capacity and crop production, the limited irrigation scheme for winter wheat with once time might be a practical alternative strategy to conserve the depleting groundwater. 【Method】In this study, we designed eight kinds of scenarios with different irrigation quotas under this limited irrigation scheme to conduct simulation using a modified SWAT model. Based on the estimated results of shallow groundwater drawdown mitigation and agricultural water saving effects, an optimization using a 0-1 linear programming was conducted at each of the 22 subbasins. Specifically, the constraint condition was set as stopping the decline of shallow groundwater table, and the objective function was set as minimizing the reduction in winter wheat yield. 【Result】①Under the limited irrigation scheme for winter wheat with once time at the jointing stage, the declining rate of shallow groundwater table in the study area would be restrained to less than 0.34 m/a on average; the amounts of shallow groundwater overexploitation for well-irrigation would be reduced by over 70% in comparison with the current situation. However, the winter wheat yield would decrease by 25%~40% averagely. ②In terms of the spatial distribution, the Daqing River Dianxi Plain in the northern part of the study area had a more satisfactory groundwater conservation effects; whereas, in the Ziya River Plain, which is located at the southern part, a higher averaged winter wheat yield performed. ③Under these optimized irrigation schemes pattern, for most counties of Baoding area, an irrigation quota of 50 mm was mainly recommended; for the counties of Xingtai and Handan areas, an irrigation quota of 40 mm was mainly recommended; for the southwest of Shijiazhuang area, the scheme with an irrigation quota of 30 mm was mainly recommended. 【Conclusion】The optimized results showed that approximately 70% of the study area could achieve shallow groundwater equilibrium under the recommended irrigation schemes pattern. These results could provide quantitative references for the implementation of an operable limited irrigation scheme (i.e., applying one round of irrigation at the jointing stage for winter wheat) in this well-irrigated area where the shallow groundwater is overdrawn. |
| Key words: Limited irrigation scheme; Shallow groundwater; Groundwater equilibrium; Crop yield; SWAT model; Optimization |
