Location: Columbia Plateau Conservation Research Center
Project Number: 2074-11120-005-007-I
Project Type: Interagency Reimbursable Agreement
Start Date: Mar 20, 2024
End Date: Aug 31, 2031
Objective:
1) Determine spatial and temporal GHG (nitrous oxide [N2O], carbon dioxide[CO2]) emissions from semiarid dryland cropping systems in eastern Oregon.
2) Determine cumulative greenhouse gas (N2O, CO2, and methane [CH4]) and ammonia (NH3) emissions from fumigated and non-fumigated potato under irrigated conditions.
3) Test the effectiveness of enhanced efficiency nitrogen fertilizer (EENF) on N2O, and NH3 emissions from non-fumigated potato-mustard or potato-winter pea cover crop and fumigated potato-mustard and winter pea cover crop.
4) Determine the effects of legume cover and/or mustard on GHG emissions and soil physical, and chemical properties in potato production system.
Approach:
We will continue measuring N2O, CO2, and CH4 emissions weekly at plot scale in the following long-term field projects: 1) winter wheat-winter wheat under no-till; 2) winter wheat-winter pea cover crop under no-till; 3) winter wheat-fallow under sweep tillage; and 4) winter wheat-winter wheat-sorghum under no-till with or without a cover crop using manually deployed static chambers following USDA-ARS GRACEnet protocols. Additionally, we will use an automated chamber system (if purchases are approved on time) to better capture greenhouse gas (GHG) emissions under mature wheat crops in these plots to determine temporal GHG changes for the wheat, pea and sorghum plants in 2025 and 2026. We will start the new treatments in irrigated non-fumigated potato fields with cover crops (pea, winter wheat, mustard) and in fumigated control potato plots. Greenhouse gas emissions will be measured weekly using manually placed static chambers in project years (2025-2027). Also enhanced efficiency nitrogen fertilizer (EENF) will be used in mustard cover crop and winter wheat/EENF in replicated treatments (4 times/treatment) in 2028-2029. Soil organic carbon, dissolved organic carbon, inorganic carbon, ammonium, nitrate, phosphate, sulfate, pH, and EC will be determined in the soil profile at the beginning and end of the experiment. Nitrogen tracer (15N) will be applied at the start of the experiment in the control and legume cover crop treatments only and nitrate plant uptake and 15N leaching in the soil profile will be monitored. A suite of ancillary data will be collected and analyzed including weather (wind direction and velocity, temperature, relative humidity, solar radiation) and soil moisture and soil temperature.
