应用Hydrus-1D模型模拟分析冬小麦农田水分氮素运移特征

将Hydrus 1D水氮联合模型用于模拟冬小麦农田水分氮素运移转化过程,试验和模拟结果表明,北京地区冬小麦农田不同水肥处理小区,蒸散量约400mm,占根层总耗水量的95%以上,水分渗漏到根层以下量很少,各小区最大渗漏量为38.4mm。作物吸氮占总耗氮量的94%以上,而根层以下氮淋失很少,最大氮淋失量为8.7kg/hm2。氮淋失量主要对应于水分渗漏量,可考虑改变灌溉措施减少水氮淋失量。传统水、肥管理方案与优化水、肥管理方案比较,各处理产量和水氮利用效率无显著差异,而前者根层水分渗漏量大并肥料总投入量大。综合评价认为,优化水肥管理措施更合理可取。

Simulation and analysis of water balance and nitrogen leaching using Hydrus-1D under winter wheat crop

Hydrus 1D model was used to simulate water flow and nitrogen transport and transform under winter wheat crop. The results showed that crop evapotranspiration in different plots with distinguished irrigation and fertilization were about 400mm, which accounted for above 95% of total water consumption in root zone. While water leakage was little with the maximum quantity of 38.4 mm. Root N uptake was the majority of total nitrogen consumption with the proportion of above 94%. While nitrogen leached was much less with the maximum quantity of 8.7 kg/hm². The amount of nitrogen leaching mainly relied on the quantity of water leakage. Water leakage and nitrogen leaching could be lessened principally by adjusting irrigation measurement. Considering higher water use efficiency, nitrogen use efficiency and less water leakage and nitrogen leaching, the optimal irrigation and fertilization treatments were reasonable and advisable.