基于APSIM模型小麦-玉米不同灌溉制度作物产量和水分利用效率分析

针对海河平原地下水位持续下降和维持小麦—玉米两熟较高产量之间的矛盾,对不同降水年型小麦—玉米不同灌溉制度下产量和水分利用效率(WUE)进行模拟分析,结果对平衡该区域地下水可持续利用与粮食生产提供重要科学决策依据.利用研究区域站点长时间序列气象数据,以小麦不同水分处理地上部生物量、叶面积和周年土壤水分动态田间试验数据为基...

Analysis of Crop Yield and Water Use Efficiency of Wheat-Maize Double Cropping System Under Different Irrigation Systems Based on APSIM Model

In view of the contradiction between the declining of groundwater table and the demand of high yield, to clarify the yield and water use efficiency (WUE) of wheat-maize double cropping system in the different precipitation years under different irrigation scenarios, the results would provide important scientific decision-making basis to balance the sustainable of groundwater utilization and grain production. Based on the field experiment data, the crop biomass, LAI and soil water content under different irrigation treatments, the genetic parameters and parameters related with the soil water were calibrated and validated by using long-term meteorological data in the APSIM wheat-maize cropping model. Using the calibrated and validated APSIM model, the water deficit index (CWDI) was analyzed in different precipitation years, the crop yield, water use efficiency (WUE), and the irrigation water use efficiency (IWUE) of 8 irrigation scenarios under the dry, medium, and rainy years were simulated. The results showed that CWDI was high in each growth stage of wheat in different precipitation years, which indicated that water requirement of wheat in dry, medium, and rainy years was much higher than precipitation, especially from jointing to maturity stage. Maize was not affected by drought stress before tasseling, but was in medium or severe drought after tasseling. Considering both yield and water use efficiency in this region, when the total irrigation water was 225 mm (75 mm at wheat sowing + 75 mm at jointing + 75 mm at flowering), the total yield was high, and the WUE and IWUE was maximal. The average total yield and WUE were 17 357.6 kg/hm² and 29.6 kg/(hm²·mm) in dry years, were 18 827.9 kg/hm² and 25.9 kg/(hm²·mm) in the medium years, and were 19 685.2 kg/hm² and 25.8 kg/(hm²· mm) in rainy years. Under this irrigation scenario, the yields of wheat and maize were high, and the WUE were also at the high level. So, this irrigation scenario was an important irrigation strategy and practice for water-grain trade-off in this region.