Some of the highest losses of nitrate to surface waters come from drained agricultural land. Given previous this article studied for Belgian farming conditions (i) the effect of subsurface drainage density on nitrate losses and (ii) the economics of nitrate emissions, using the nitrogen version of DRAINMOD (Brevé et al., 1997 a and b). DRAINMOD (Skaggs, 1997) was used to simulate the performanc...

abstract although lateral drains play the main role in removal of excess water from soil profile in subsurface drainage systems, but it is assumed that perforated collectors can directly remove a part of drainwater from soils. this part of discharge in subsurface drains is not usually taken into consideration in drainage design criteria, due to lack required information and its difficult estima...

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...

Phosphorus application in excess of crop needs has increased the concentration of P in surface soil and runoff and led many states to develop P-based nutrient management strategies. However, insufficient data are available relating P in surface soil, surface runoff, and subsurface drainage to develop sound guidelines. Thus, we investigated P release from the surface (0-5 cm depth) of a Denbigh ...

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...

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...

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...

surface and subsurface water collection in small seasonal rivers is very crucial, particularly in dry seasons. in this study a type of intake is introduced which acts as a river drainage network. an experimental model of the subsurface intake was constructed and the effective parameters such as upstream discharge, installation depth, and drain intervals were evaluated. the results showed that t...

Nonpoint source contamination of surface and groundwater resources with nitrate-N (NO3-N) has been linked to agriculture across the midwestern USA. A 4-yr study was conducted to assess the extent of NO3-N leaching in a central Iowa field. Water flow rate was monitored continuously and data were stored on an internal datalogger. Water samples for chemical analysis were collected weekly provided ...

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...