Location: Agroecosystems Management ResearchTitle: Saturated riparian buffers as promising edge-of-field conservation practice
|KATUWAL, SHEELA - Orise Fellow|
|JOHNSON, GABRIEL - Iowa State University|
|Malone, Robert - Rob|
|JAYNES, DAN - Retired ARS Employee|
|ISENHART, THOMAS - Iowa State University|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 3/14/2023
Publication Date: 8/6/2023
Citation: Rogovska, N.P., Cole, K.J., Katuwal, S., Johnson, G., Malone, R.W., Jaynes, D., Isenhart, T. 2023. Saturated riparian buffers as promising edge-of-field conservation practice [abstract]. SWCS International Annual Conference.
Technical Abstract: Excessive nitrate in surface waters is a key factor causing degradation of water quality locally and a major cause of the hypoxic zone in the northern Gulf of Mexico. Numerous conservation practices have been proposed to reduce nitrates entering streams including in-field practices such as fertilizer management or cover crops implementation, and field-edge practices such as bioreactors. A saturated riparian buffer is a novel field-edge practice developed to remove nitrates from artificial subsurface drainage before it reaches surface waters by diverting tile water into riparian buffer soil via shallow distribution pipes. As diverted drainage infiltrates from the distribution pipe into the buffer soil, nitrate is removed primarily by denitrification and plant uptake. Saturated buffers were shown to remove an average of 63.7 ± 65.9 kg N/y (n = 47 site-years across Iowa, Illinois, Indiana, and Minnesota). In addition, the percentage of nitrate-N removed from diverted flow averaged 82 ± 22% across 29 site-years in Iowa and Illinois. The nitrate removal efficiency variance can be explained by numerous factors impacting saturated buffer performance including site design, soil characteristics, and climatic condition. Overview of the past studies in Iowa and other states and current research and outreach activities related to saturated buffer performance within the South Fork of the Iowa River watershed will be presented.