Protecting Surface Water with Healthy Soils and Cover Crops
Reduction of phosphorus (P) loss from agricultural systems is a national concern because P inputs to surface water increases the likelihood of harmful algal blooms that deteriorate water quality. Including cover crops in agricultural systems could help reduce P loss from soils and applied fertilizers. Cover crops can reduce P loss and protect water quality by improving soil health, which can in-turn increase infiltration and reduce runoff. However, there is very little direct evidence of this in field-scale row-crop production. We need more information linking soil health benefits to water quality protection because producers will be more likely to include cover crops in their cropping systems if they see direct evidence of cover crop impacts on improved soil health, reduced water loss (runoff), and increased water quality protection.
The goal of this project is to demonstrate that adoption of cover crop systems will improve soil health, reduce P loss, and protect water quality. Our objectives are to quantify the effects of cover crops on: i) surface runoff and P loss, ii) soil health, and ii) temporal trends of near-surface soil moisture. By achieving these objectives, we will identify specific mechanisms by which cover crop integration can reduce runoff, sediment loss, and nutrient loss. We will further demonstrate that improved soil health results in decreased runoff, sediment, and nutrient loss. The data collected through this project will be part of a long-term dataset for edge-of-field water quality monitoring and soil health management systems, thus laying the foundation for long-term demonstrations of cropping system effects on soil health improvement and water quality protection.
This proposal directly addresses the resource concern of water quality protection stated in the Conservation Innovation Grants Fiscal Year 2016 Announcement for Program Funding. Our project will quantify impacts of cover crop adoption on water quality through edge-of-field water quality monitoring (runoff, sediment loss, and P loss) from 18 small watersheds as part of the Kansas Agricultural Watershed (KAW) project. We will cooperate with an EQIP-eligible producer to measure these same parameters with an on-farm demonstration study. We will quantify impacts of cover crop use on soil health parameters by measuring aggregate stability, glomalin, phospholipid fatty acids, active C, dissolved organic C, dissolved organic N, nitrate, and ammonium in soil. This project will provide datasets on cover crop effects on water quality and soil health. The results of this project will be summarized in a series of extension factsheets entitled “Healthy Soil Healthy Water.”
Project timeline
October 2016 to September 2019
