Quantifying the Water Quality Impacts of Implementing Cover Crops
Soil Drainage Research
2012 Annual Report
1a.Objectives (from AD-416):
Quantify the impacts of cover crops on tile drained lands.
1b.Approach (from AD-416):
We will use a field based approach with automated samplers and compound weirs located on the outlets of two subsurface tile mains (one draining land with cover crops and one draining land with no cover crops). Samples will be collected for a 2 year period and analyzed for nutrient concentrations. This paired approach will permit quantification of water quality benefits of implementing cover crops.
As part of the Cooperative Conservation Partnership Initiative (CCPI) grant awarded to the Upper Big Walnut Creek watershed we have worked with the Delaware Soil and Water Conservation District, the local National Resources Conservation Service, and the Environmental Defense Fund to promote the use of cover crops in the watershed. To date interest in cover crops has increased and approximately 2,500 acres of cover crops have been planned or have already been planted in our study watershed. We have instrumented eight edge-of-field sites within the watershed to document the hydrology and water quality benefits of cover crops. The instrumentation was recently completed and we are collecting hydrology and nutrient loss data from those sites. At two of the fields, subsurface drainage discharge is also being collected and analyzed for nutrient content.
The work and progress associated with this project supports objective 1 of the 2012-2016 project plan, specifically sub-objective 1a: Quantify the influence of conservation practices on surface discharge and water chemistry in the agricultural landscape and sub-objective 1b: Conduct field and watershed-scale studies of hydrology, nutrient, and agrichemical contributions originating from subsurface drainage.