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在美国爱达荷州南部，大豆普遍采用地面灌溉，由于对灌溉系统的设计和管理不当，造成水资源严重浪费和泥沙大量流失。通过对不同坡度沟的比较，研究坡度对径流量、入渗量、产沙量的影响；同时利用溴化物作示踪物，观测化学物质的横向输移情况；并对部分沟进行秸秆覆盖，测定其对径流量、入渗量、产沙量及溴化物输移的影响。结果表明；坡度对灌溉效率的影响很大，随着坡度的增大，径流量和产沙量均增大，入渗量减小；秸秆覆盖能大大减小径流量，减少泥沙量９９％～１００％，同时还能提高溴化物的横向输移能力。应用运动波模型模拟表明选择适当的入流流量和灌溉持续时间，灌溉平均效率能由４４％提高到５８％。
In southern Idaho, the United States generally uses surface irrigation of soybeans. Due to improper design and management of irrigation systems, it has resulted in serious waste of water resources and massive loss of sediment. The effects of slope on runoff, infiltration and sediment yield were studied through comparison of different slope ditch. At the same time, bromide was used as tracers to observe the horizontal transport of chemical substances. Straw was covered in some ditches, The effects of runoff, infiltration, sediment yield and bromide transport were determined. The results showed that the slope had a great influence on the irrigation efficiency. With the increase of slope, the runoff and sediment yield both increased and the infiltration rate decreased. The straw mulching could greatly reduce the runoff and reduce the sediment yield by 99% ~ 100%, while also improving the lateral transport capacity of bromide. The application of the motion wave model shows that the average irrigation efficiency can be increased from 44% to 58% by selecting the appropriate inflow and irrigation duration.