Location: Cropping Systems and Water Quality ResearchTitle: Use of improved nutrient practices in maize-based agroecosystems alter allocation between leaching and denitrification loss pathways
|EAGLE, ALISON - Environmental Defense Fund|
|MCCLELLAN MAAZ, TAI - University Of Hawaii|
|HELMERS, MATTHEW - Iowa State University|
|BROUDER, SYLVIE - Purdue University|
|CHRISTIANSON, LAURA - University Of Illinois|
|DRURY, CRAIG - Agriculture And Agri-Food Canada|
|FERNANDEZ, FABIAN - University Of Minnesota|
|GENTRY, LOWELL - University Of Illinois|
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., Eagle, A., Mcclellan Maaz, T., Helmers, M., Brouder, S., Christianson, L., Drury, C., Emmett, B.D., Fernandez, F., Gentry, L. 2022. Use of improved nutrient practices in maize-based agroecosystems alter allocation between leaching and denitrification loss pathways [abstract]. American Geophysical Union Fall Meeting, December 12-16, 2022, Chicago, Illinois.
Technical Abstract: Sustainability in maize-based agroecosystems requires the ability to consider both productivity and environmental tradeoffs and synergies. The addition of soluble fertilizers, primarily nitrogen, is a primary concern due to off-site nutrient losses. A key challenge to-date in conducting systems-level analyses is the lack of multi-site, multi-year data with robust nutrient measurements across multiple loss pathways. This presentation examines nutrient changes across intensively managed maize-based experiments in the U.S. Midwest and Ontario, Canada (spanning 39.4 to 44.2 °N and 82.7 to 95.5 °W). Research was conducted from 2018-2020 at nine (9) field sites in six (6) states/provinces using standardized protocols for water, greenhouse gas, agronomic, and soil measurements. Experiments included common “farmer-normal” practices and improved nutrient management practices including cover crops and altered nitrogen fertilizer timing, placement, and rate. Data included nitrate-N load from water outflow, nitrous oxide and ammonia gaseous fluxes, nitrogen content in grain, soil carbon and soil health attributes, farm management, and on-site precipitation. Overall, more nitrogen was lost from the system as nitrate-N rather than nitrous oxide although the proportion varied temporally and spatially. The nutrient loss patterns were represented as the ratio between different reactive N forms with each field site being unique. For greatest improvement in sustainability, identification of the greater loss pathway (leaching or denitrification) is the first step at a location followed by implementation of location-specific interventions.