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Subsurface drainage is a common practice in many agricultural watersheds in the Mid-Western region of the United States. A typical drainage system in east central Illinois is not spaced in a parallel manner, but the subsurface drain lines are laid out in a random and irregular fashion. These subsurface drain lines most often discharge into numerous man-made drainage channels, which ultimately drain to the rivers and the reservoirs. The Little Vermilion River (LVR) watershed in east central Illinois, USA is an example of a watershed with altered hydrology from subsurface drainage systems. A continuous monitoring study has been conducted from 1991 to 2003 on this watershed to quantify the effects of cropping management...
Coupled Transport and Geochemical Processes Determining the Fate of Chemicals in Surface Waters
Water quality and pollution contamination depend strongly on geochemical processes involving reactions with mineral surfaces and substrates. Such processes include weathering reactions that contribute dissolved chemicals, sorption that removes aqueous species, and electron transfer mechanisms that establish redox conditions. Although extensive research has been conducted on the aqueous chemistry, minimal information exists on the corresponding solid phases and their effects on chemical transport. Objectives of this project are to: investigate the composition and structure of common mineral surfaces and determine the extent of heterogeneity between specific surfaces and the bulk mineral phase; determine the mechanism...
Toxic contaminants and naturally occurring substances found in the subsurface can exist in multiple phases, and undergo complex reactions including biodegradation. A comprehensive and quantitative understanding of the processes controlling the fate and transport of subsurface contaminants is necessary to develop policies and strategies for managing water-quality conditions in different land use and environmental settings. Numerical models that simulate flow, transport, and reactions are useful tools for understanding the fate of chemicals in the subsurface when used in conjunction with field and laboratory studies. The research efforts of this project consider flow and chemical behavior in the saturated and unsaturated...
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This USGS data release contains 2013 streamflow, baseflow, and precipitation data from three hydrologically-diverse streams in the United States used to develop a conceptual framework for effectively anticipating water-quality changes resulting from changes in agricultural activities. The framework combined generalized concepts on the movement of water, the environmental behavior of chemicals and eroded soil, and the designed functions of various agricultural activities. The framework addresses the impacts on water quality of a broad range of agricultural chemicals and sediment across a variety of hydrologic settings. • Chesterville Branch near Crumpton, Maryland, (USGS site ID - 01493112) had substantial baseflow...
    map background search result map search result map Data set used to develop a conceptual framework for effectively anticipating water-quality changes resulting from changes in agricultural activities Data set used to develop a conceptual framework for effectively anticipating water-quality changes resulting from changes in agricultural activities