Co-benefits of climate change mitigation from innovative agricultural water management: a case study of corn agroecosystem in eastern Canada

Beneficial water management practices (BWMPs) have been identified to reduce greenhouse gas (GHG) emissions in eastern Canada by retrofitting conventional tile drainage with controlled drainage and sub-irrigation. Implementing these practices may also yield additional benefits for farmers and society besides GHG emissions mitigation. This study employs a conceptual framework to quantify the co-benefits of adopting BWMPs in a corn agroecosystem in eastern Canada. The assessment combines financial analysis and life cycle assessment to compare the implementation of BWMPs with the Base technology. This study was based on field experiments for corn production under BWMPs and Base technology during the 2014 and 2015 growing seasons in St. Emmanuel, Quebec. Co-benefits were estimated by calculating the differences in net present value and environmental costs resulting from implementing BWMPs compared with Base technology. The findings show that co-benefits range from $129.42 to $142.03 per hectare under median environmental prices and $158,29 to $231.74 per hectare under upper environmental prices for a 20-year life expectancy of BWMPs implementation. In conclusion, this study underscores the significance of understanding the co-benefits associated with the innovative water management system, as it supports climate change mitigation and adaptation measures at the farm scale. The positive co-benefits highlight the economic and social advantages of implementing BWMPs alongside GHG emission mitigation. Nevertheless, these co-benefits may not be sufficient to encourage voluntary adoption among farmers. Therefore, policymakers should consider implementing supportive policy instruments like green payments and extension activities to facilitate the adoption of BWMPs.