In order to investigate the characteristics of migration and losses for different land utilization patterns in each rain event, the migration laws and losses characteristics of nitrogen and phosphorus from farmland surface runoff for different land utilization patterns in Ganjiang River basin were analyzed according to the experimental data of each rain event. The result shows that the loss of nitrogen was mainly in the form of nitrate nitrogen, and the loss of phosphorus was mainly in the form of dissolved phosphate. The content of total nitrogen, nitrate and ammonium nitrogen increased at first, and then decreased gradually, whereas the total phosphorus and phosphate contents were stable relatively, and the loss of lower content during a rain event. The retention rate of total nitrogen, ammonium nitrogen, nitrate, total phosphorus and phosphate for farmland ditch system are 50.0%, 47.5%, 51.5%, 53.0%and 36.6%, respectively, inflecting that the retentions of nitrogen and phosphorus are higher under rainfall conditions, which reflect that the retention of nitrogen and phosphorus in farmland ditch system may be related to the growth of aquatic plants and the characteristics of the soil at the bottom of ditch. The land utilization patterns have an effect on the content of the nitrogen and phosphorus, and small differences of nitrogen and phosphorus mean content were observed among different land utilization patterns. The research shows that different land utilization patterns in Ganjiang river watershed has certain influence on the loss of nitrogen and phosphorus in surface runoff, and need make corresponding prevention measures of nitrogen and phosphorus loss for different land utilization patterns.%为了解在次降雨径流条件下不同类型农田地表径流中氮磷的迁移与流失特征，基于次降雨径流试验数据，探讨了赣江流域不同土地利用类型下地表径流氮磷迁移规律与流失特征。结果表明：氮流失的主要形态为硝态氮，磷流失的主要形态为磷酸盐；次降雨径流过程中总氮、硝态氮与铵态氮流失质量浓度呈先增大后逐步降低的趋势，而总磷与磷酸盐流失质量浓度变化相对平稳，且流失质量浓度相对较低。农田沟渠系统对总氮的截留率约为50.0%，对铵态氮的截留率约为47.5%，而对硝态氮的截留率则达到51.5%，而对总磷与磷酸盐的截留率分别约为53.0%与36.6%，说明农田沟渠系统在降雨条件下对径流中的氮、磷具有较高的截留作用，反映了农田沟渠径流中不同形态氮磷的截留可能与沟渠系统中的杂草等水生植物的生长情况以及沟渠底部土壤的特性有关。此外，不同土地利用类型对地表径流中氮磷的流失具有一定的影响，表现为两种典型土地利用类型的降雨径流中氮、磷流失的平均质量浓度具有一定差异，两种土地利用类型地表径流中不同形态氮、磷流失量的大小顺序为菜地>水田。研究表明，赣江流域不同的土地利用类型对地表径流中氮磷流失量具有一定的影响，需针对赣江流域不同土地利用类型，制定相应的氮、磷流失的防治措施。
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