限量灌溉下冬小麦水分利用效率模拟

Water use efficiency of winter wheat under limited irrigation:A simulation study.

用参数调试后的DSSAT-CERES Wheat模型,以郑州地区冬小麦全生育期降水偏缺的2003—2004年逐日气象资料为背景数据,在分析作物阶段缺水量的基础上,限定灌溉量100mm以内,分不灌水、灌一水、二水、三水处理,着重模拟研究限量灌溉对冬小麦水分利用的影响,并引入田间水分管理反映指标(WMRIs)为优化灌溉方案设计提供综合评价参考。结果表明:限量灌溉可在一定程度上缓解水分胁迫,促进增产并提高水分利用效率;各种处理均较不灌水明显增产,增产率为13.1%～73.3%;小麦对水分的吸收利用总体表现为灌二水优于灌三水优于灌一水;水分利用效率越冬水+灌浆水最高,灌溉水利用效率拔节水最高;拔节期是限量灌溉的最佳时期。

Based on the daily meteorological data of Zhengzhou in 2003-2004 when the precipitation in winter wheat growth season was of somewhat shortage, the water deficit at different growth stages of winter wheat was analyzed, and the effects of limited irrigation on the water use efficiency （WUE） of winter wheat were studied with the DSSAT-CERES Wheat model after parameter calibration. Four treatments were designed, i. e. , no irrigation, irrigation once, twice, and three times with limited （100 mm） water, and water management response indicators （WMRIs） were introduced as an integrative evaluation reference for the design of optimal irrigation schemes. Limited irrigation alleviated water stress to some extent, and promoted the grain yield and WUE. Comparing with no irrigation, limited irrigation increased the grain yield by 13. 1%- 73.3%. Irrigation twice showed the best effect in promoting the water absorption and utilization by winter wheat, followed by irrigation three times, and irrigation once. The WUE was the highest when watering at wintering and grain-filling stages, while the utilization efficiency of irrigation water reached the highest when watering at elongation stage. Therefore, elongation stage was the best phase to actualize limited irrigation.