Location: Cropping Systems and Water Quality Research
Title: Regional and seasonal differences in nitrate-N (NO3-N) load in U.S. agroecosystems instrumented with water quality conservation practicesAuthor
Abendroth, Lori | |
HELMERS, MATTHEW - Iowa State University | |
REINHART, BENJAMIN - Purdue University | |
CHIGHLADZE, GIORGI - Iowa State University | |
PEASE, LINDSAY - University Of Minnesota | |
BOWLING, LAURA - Purdue University | |
YOUSSEF, MOHAMED - North Carolina State University | |
GHANE, EHSAN - Michigan State University | |
AHIABLAME, LAURENT - University Of California | |
BROWN, LARRY - The Ohio State University |
Submitted to: American Geophysical Union Meeting Abstract
Publication Type: Abstract Only Publication Acceptance Date: 8/3/2022 Publication Date: 12/12/2022 Citation: Abendroth, L.J., Helmers, M., Reinhart, B., Chighladze, G., Pease, L., Bowling, L., Youssef, M., Ghane, E., Ahiablame, L., Brown, L. 2022. Regional and seasonal differences in nitrate-N (NO3-N) load in U.S. agroecosystems instrumented with water quality conservation practices [abstract]. American Geophysical Union Fall Meeting, December 12-16, 2022, Chicago, Illinois. Interpretive Summary: Technical Abstract: This presentation examines water quality research conducted in thirteen (13) agricultural experiments across six (6) states in the U.S. Midwest and North Carolina, USA. These regions have significant acreage with subsurface artificial drainage installed 0.6 to 1.0 m below the soil surface. This infrastructure reduces time periods of waterlogged or overly saturated soils for optimum crop productivity. A conservation practice explored for these drained fields is termed controlled drainage; the outflow is altered from freely flowing to controlled at particular times, either manually by the farmer or through automated systems. By managing the water outflow, it is possible to retain more water in the field for potential future periods of low rainfall and also reduce downstream nitrate-N (NO3-N) load. Nitrate load is a product of drain flow and nitrate-N concentration. Here, we present the complexity in managing drained fields for water quality benefits across a region varying substantially in timing of precipitation and freeze-thaw. Experiments located in more northern and western regions had a greater percentage of annual drain flow occurring in spring months. The controlled drainage practice was effective in reducing nitrate-N load due to reductions in water outflow; however, the nitrate-N concentration was not reduced. The timing of the greatest nitrate-N load reductions varied, shifting from winter to spring as one moved north and west in the study area. These regional and seasonal differences have implications for reducing nitrate-N load due to field operability considerations and constraints. Data for this analysis are published at the USDA National Ag Library as part of the Transforming Drainage project (https://doi.org/10.15482/USDA.ADC/1521092). |