Best management practices (BMPs) play an important role in improving impaired water quality from conventional row crop agriculture. In addition to reducing nutrient and sediment loads, BMPs such as fertilizer management, reduced tillage, and cover crops could alter the hydrology of agricultural systems and reduce surface water runoff. While attention is devoted to the water quality benefits of BMPs, the potential co‐benefits of flood loss reduction are often overlooked. This study quantifies the effects of selected commonly applied BMPs on expected flood loss to agricultural and urban areas in four Iowa watersheds. The analysis combines a watershed hydrologic model, hydraulic model outputs, and a loss estimation model to determine relationships between hydrologic changes from BMP implementations and annual economic flood loss. The results indicate a modest reduction in peak discharge and economic loss, although loss reduction is substantial when urban centers or other high‐value assets are located downstream in the watershed. Among the BMPs, wetlands, and cover crops reduce losses the most. The research demonstrates that watershed‐scale implementation of agricultural BMPs could provide benefits of flood loss reduction in addition to water quality improvements.

中文翻译：

---

从农业最佳管理实践中减少洪水风险

最佳管理规范（BMP）在改善常规row作农业的水质受损方面发挥着重要作用。除了减少营养和沉积物负荷外，BMP（例如肥料管理，减少耕种和覆盖作物）还可以改变农业系统的水文状况，并减少地表水径流。尽管人们关注BMP的水质优势，但减少洪水损失的潜在共同利益往往被忽视。这项研究量化了一些常用的BMP对爱荷华州四个流域的农业和城市地区预期的洪灾损失的影响。该分析结合了分水岭水文模型，水力模型输出和损失估算模型，以确定BMP实施带来的水文变化与年度经济洪灾损失之间的关系。结果表明，尽管城市中心或其他高价值资产位于流域的下游，但峰值排放量和经济损失有所减少，尽管损失减少是可观的。在BMP中，湿地和有盖作物减少的损失最大。研究表明，在流域范围内实施农业BMP不仅可以改善水质，还可以减少洪灾损失。