Field-to-Stream Transport of Agricultural Chemicals and Sediment in an Iowa Watershed. Part 2. Data Base for Model Testing (1979-1980)

摘要

In a continuation of a previous project, data were collected on the field-to-stream transport of sediment, nutrients, and pesticides in an agricultural watershed. These data contribute to an improved qualitative understanding of the field-to-stream processes involved and provide a quantitative base for testing mathematical models that predict hydrology, erosion, and sediment and chemical transport. During the study reported here (1979-1980), data were collected for small corn, soybean and pasture fields; for two larger mixed-cover subwatersheds; and at three drainage stream sites. Rainfall was well above average in 1979 and slightly below normal in 1980. Flow from the watershed was roughly half subsurface flow and half runoff, with about half of the surface runoff being snowmelt.