Energy Systems Division, Argonne National Laboratory, Lemont, IL 60439, USA.
Limno Tech, Environmental Laboratory, U.S. Army Engineer R&D Center, USA.
Sci Total Environ. 2018 Sep 1;635:1585-1599. doi: 10.1016/j.scitotenv.2018.03.184. Epub 2018 Apr 24.
A watershed model was developed using the Soil and Water Assessment Tool (SWAT) that simulates nitrogen, phosphorus, and sediment loadings in the Lower Mississippi River Basin (LMRB). The LMRB SWAT model was calibrated and validated using 21 years of observed flow, sediment, and water-quality data. The baseline model results indicate that agricultural lands within the Lower Mississippi River Basin (LMRB) are the dominant sources of nitrogen and phosphorus discharging into the Gulf of Mexico. The model was further used to evaluate the impact of biomass production, in the presence of riparian buffers in the LMRB, on suspended-sediment and nutrient loading discharge from the Mississippi River into the Gulf of Mexico. The interplay among land use, riparian buffers, crop type, land slope, water quality, and hydrology were anlyzed at various scales. Implementing a riparian buffer in the dominant agricultural region within the LMRB could reduce suspended sediment, nitrogen, and phosphorus loadings at the regional scale by up to 65%, 38%, and 39%, respectively. Implementation of this land management practice can reduce the suspended-sediment content and improve the water quality of the discharge from the LMRB into the Gulf of Mexico and support the potential production of bioenergy and bio-products within the Mississippi River Basin.
利用土壤和水评估工具（SWAT）开发了一个流域模型，用于模拟密西西比河流域下游（LMRB）的氮、磷和泥沙负荷。使用 21 年的观测流量、泥沙和水质数据对 LMRB SWAT 模型进行了校准和验证。基线模型结果表明，密西西比河流域下游（LMRB）的农业用地是向墨西哥湾排放氮和磷的主要来源。该模型进一步用于评估在密西西比河流域存在河岸缓冲带的情况下，生物质生产对密西西比河向墨西哥湾输送的悬浮泥沙和养分负荷的影响。在不同尺度上分析了土地利用、河岸缓冲带、作物类型、土地坡度、水质和水文学之间的相互作用。在 LMRB 主要农业区实施河岸缓冲带可以使区域尺度上的悬浮泥沙、氮和磷负荷分别减少 65%、38%和 39%。实施这种土地管理措施可以减少悬浮泥沙含量，提高 LMRB 排入墨西哥湾的排放水的水质，并支持密西西比河流域内生物能源和生物产品的潜在生产。
