水稻节水条件下氮素的利用及环境效应分析  

Analysis on nitrogen utilization and environmental effects under water-saving irrigation in paddy field

作　　者：邵东国[1] 李颖[1] 杨平富[2] 高明利[2] 

机构地区：[1]武汉大学水资源与水电工程科学国家重点实验室,湖北武汉430072 [2]湖北省漳河工程管理局,湖北荆门448156

出　　处：《水利学报》2015年第2期146-152,共7页Journal of Hydraulic Engineering

基　　金：国家自然科学基金(51379150;51439006);国家"十二五"科技支撑计划项目(2012BAD08B05-3)

摘　　要：为了揭示稻田不同节水灌溉与施肥管理方式下氮素迁移转化与利用损失规律,以指导水稻田的水肥管理,以水稻生育期田间水分氮素监测试验为基础,运用Hydrus-1D结合一阶动力学方法建立模型,对不同节水灌溉、肥料管理条件下的氮素运移进行模拟,并以反演的综合一阶动力学系数作为统一的评价指标,对不同方案处理下的氮素利用效率及环境效应进行分析评价。结果表明,植物吸收利用对于分蘖期、拔节孕穗期和抽穗开花期土壤水中氮素变化速率的影响比较显著;而氮素的主要损失差异在于分蘖肥和拔节肥导致的分蘖期和拔节孕穗期氨挥发损失效率大,以及分蘖期、抽穗开花期和乳熟期NO3-的反硝化作用造成的氮素变化差异明显;浅灌深蓄(G1)的NO3-综合一阶动力学系数较浅勤灌溉(G2)小,NO3-损失速率较小;施用氮肥(135 kg/hm2)(F1)施肥模式、(G1)灌溉模式下的植物吸收效率较另两种模式高,对应产量也较高;建议采用浅灌深蓄(G1)的节灌方式,同时采取分次施肥、深施等措施减少氨挥发损失,对于提高稻田氮素利用率尤为重要。In order to investigate the movement and transformation processes of nitrogen in paddy field un-der water- saving irrigation and fertilization management, experiments of the water and nitrogen measure-ments were conducted during the rice growth period. The model based on the Hydrus-1D and the first-or-der kinetics has been developed to simulate the transformation processes of nitrogen under the different wa-ter and nitrogen treatments,and to inverse the comprehensive coefficient of first-order kinetics. A compre-hensive coefficient of the first-order kinetics is adopted as the evaluation index to estimate the utilization efficiency of nitrogen and to evaluate the impact of irrigation water and fertilizer N input on the environment.The results show that plant uptake is outstanding during the tillering stage,jointing-booting stage,and flow-ering stage,while the nitrogen losses is remarkable by the ammonia volatilization at the tillering stage andjointing- booting stage and the denitrification at the tillering stage, flowering stage, and milk- ripe stage.The comprehensive coefficient of the first- order kinetics of NO3^- under the shallow- irrigation and deep-sluice model（G1） is smaller than that under the shallow-wet irrigation（G2）,which indicates the smallerrate of NO3^-loss in the G1 case. The ratio of plant uptake and yield under the fertilization pattern（135 kg/hm^2）（F1） or shallow-irrigation and deep-sluice model（G1） is higher than the others. Thus the shallow-irri-gation and deep-sluice model（G1） and more nitrogen supply splits is beneficial to decrease nitrogen loss-es and improve nitrogen efficiency.

关 键 词：节水灌溉 HYDRUS-1D 一阶动力学系数 氮素 

分 类 号：X592[环境科学与工程—环境工程]