Gray, Richard2023-03-172023-03-1720232023-022023-03-17February 2https://hdl.handle.net/10388/14524This thesis examines privately and socially optimal nitrogen (N) fertilizer rates for Canola production in Saskatchewan. In 2018 nitrous oxide (N2O) emissions from agricultural soils accounted for approximately 42% (in CO2eq) of all Canadian agricultural greenhouse gas emissions. In 2020 the Government of Canada set a national target of reducing absolute levels of GHG emissions from fertilizer application by 30% from 2020 levels by the year 2030. Canola is the largest N using crop in Canada and therefore optimizing N fertilizer use in this crop is of great importance. A canola production function is estimated using a large (n = 47,059) producer-reported data set from Saskatchewan Crop Insurance Corporation on field-level canola management over the years 2011-2019 and a wide variety of spatial and climatic conditions. The estimated implied canola N response curve was combined with price information and previous estimates for direct N2O emissions to estimate the marginal abatement cost curves and compare the observed applied N fertilizer rates to the estimated privately optimal rates and socially optimal rates. The results of this study support the previous findings of a nearly flat pay-off function for N fertilizer in crop production. On average, Saskatchewan canola producers do not appear to be overapplying nitrogen relative to the estimated privately optimal N rate. Regulation to reduce nitrogen fertilizer application rates by 30% from the privately optimal rate were found to result in net social welfare losses for canola cropping systems in Saskatchewan. When applying a N2O tax using the highest carbon price in the Canadian governments’ schedule of $170/t CO2eq for 2030, N rates are estimated to be reduced from the privately optimal rate by only 12.3% – 14.6% in the black soil zone and 6.12% – 6.92% in the brown soil zone. Given the heterogeneity in emissions factors across ecoregions and nitrogen management practices, focusing on the 4R’s of Nutrient Stewardship, agronomic research, and extension to improve N management and optimize fertilizer use are better opportunities to reduce emissions as opposed to a uniform mandatory reduction in N rates.application/pdfenoptimal nitrogen rateyield responsegreenhouse gas abatementnitrogen tax4R nutrient stewardshipThesis2023-03-17