The Root Zone Water Quality Model (RZWQM, V 3.25) was used to simulate the effect of swine manure applications on nitrate-nitrogen (NO3-N) concentrations in subsurface drain water from continuous corn for Iowa soils. Measured values of subsurface drain flow, NO3-N concentrations in drainage water, and residual NO3-N in the soil profile from three chisel plow plots were available for the growing...

Riparian buffers are a proven practice for removing NO from overland flow and shallow groundwater. However, in landscapes with artificial subsurface (tile) drainage, most of the subsurface flow leaving fields is passed through the buffers in drainage pipes, leaving little opportunity for NO removal. We investigated the feasibility of re-routing a fraction of field tile drainage as subsurface fl...

The changes in hydrological conditions observed nowadays require economical use of water. This applies to water management both on a national scale and river basins catchments, as well the drainage systems individual networks. Outflow regulation is carried out by extending outflow time surface collected during rainfall various forms retention catchment area. One devices for regulating groundwat...

A 20-m-wide trench was excavated to bedrock on a hillslope at the Panola Mountain Research Watershed in the Piedmont region of Georgia to determine the effect of upslope drainage area from the soil and bedrock surfaces on the geochemical evolution of base cation concentrations in subsurface flow. Samples were collected from ten 2-m sections and five natural soil pipes during three winter rainst...

Tile drains and French drains are typically used to control subsurface drainage, especially on greens and fairways with shallow water tables or fine soil texture. Tile drains are defined as "drains constructed by laying drain tile with unsealed joints in the bottom of a trench which is then refilled," whereas French drains are a "type of drain consisting of an excavated trench, refilled with pe...

43 A is an important water management practice in the midwestern United States to remove excess water from poorly drained areas and to provide traffi cable conditions for agricultural production. About 30% of the total land area and 50% of the crop land in Indiana is subsurface drained (Economic Research Service, 1987). Th ere are growing concerns about the potential negative environmental impa...

in tunisia, kalâat el andalous irrigated district is one of the most affected areas by salinization. the objective of this study was to predict the root zone salinity (over 10 years) in this area using the saltmod simulation model for subsurface drainage system. saltmod is based on water balance, salt balance model, and seasonal agronomic aspects. in the pilot area, irrigated vegetables crops s...