title: Quantifying effects of soil heterogeneity on groundwater pollution at four sites in USA.
abstract: Four sites located in the north-eastern region of the United States of America have been chosen to investigate the impacts of soil heterogeneity in the transport of solutes (bromide and chloride) through the vadose zone (the zone in the soil that lies below the root zone and above the permanent saturated groundwater). A recently proposed mathematical model based on the cumulative beta distribution has been deployed to compare and contrast the regions' heterogeneity from multiple sample percolation experiments. Significant differences in patterns of solute leaching were observed even over a small spatial scale, indicating that traditional sampling methods for solute transport, for example the gravity pan or suction lysimeters, or more recent inventions such as the multiple sample percolation systems may not be effective in estimating solute fluxes in soils when a significant degree of soil heterogeneity is present. Consequently, ignoring soil heterogeneity in solute transport studies will likely result in under- or overprediction of leached fluxes and potentially lead to serious pollution of soils and/or groundwater. The cumulative beta distribution technique is found to be a versatile and simple technique of gaining valuable information regarding soil heterogeneity effects on solute transport. It is also an excellent tool for guiding future decisions of experimental designs particularly in regard to the number of samples within one site and the number of sampling locations between sites required to obtain a representative estimate of field solute or drainage flux.
authors.affiliation: Wageningen University, Department of Environmental Sciences, Sub-department Water Resources, The Netherlands.
authors.forename: Saskia
authors.initials: S
authors.lastname: Vuurens
authors.forename: Frank
authors.initials: F
authors.lastname: Stagnitti
authors.forename: Gerrit
authors.initials: G
authors.lastname: de Rooij
authors.forename: Jan
authors.initials: J
authors.lastname: Boll
authors.forename: Ling
authors.initials: L
authors.lastname: Li
authors.forename: Marc
authors.initials: M
authors.lastname: LeBlanc
authors.forename: Daniel
authors.initials: D
authors.lastname: Ierodiaconou
authors.forename: Vince
authors.initials: V
authors.lastname: Versace
authors.forename: Scott
authors.initials: S
authors.lastname: Salzman
mesh_terms: D001965:Bromides / Q000032:analysis; D002712:Chlorides / Q000032:analysis; D003691:Delaware; D008962:Models, Theoretical; D009518:New York; D012987:Soil / Q000032:analysis*; D012989:Soil Pollutants / Q000032:analysis*; D014872:Water Movements; D014873:Water Pollutants / Q000032:analysis*
chemical_list: D001965:Bromides; D002712:Chlorides; D012987:Soil; D012989:Soil Pollutants; D014873:Water Pollutants