Can farms produce to the max and still reduce greenhouse gas emissions?
Decarbonising agriculture is critical for the US to achieve net-zero emissions by 2050. A new data-driven approach looks at practices that are good for the planet and profitable for farmers.
The world relies on American farmers to do much more than just set tables. In addition to producing food for humans and animals, American farmers produce raw materials for the production of biofuels.
In addition, the agricultural industry contributes about 10% of greenhouse gas (GHG) emissions in the US. As the amount of land earmarked for agriculture is limited, farmers need to find more ways to operate efficiently, sustainably and profitably while reducing greenhouse gas emissions. With new practices, on-farm farmers can create a net sink of CO. to make2enabling the US to reach its goal of reaching net-zero emissions by 2050.
Sustainable intensification is a two-pronged approach that many believe could help. It seeks to optimize land use and management practices for maximum farmland productivity while minimizing the associated environmental impact. The trick is to find the right balance between the two objectives.
Scientists specializing in agroecosystems modeling and life cycle assessment (LCA) at Colorado State University (CSU) and the U.S. Department of Energy’s (DOE) Argonne National Laboratory approached the problem in a new analytical way in a recent research into agriculture of maize and soy. in Iowa. They co-authored an article, “A Multi-Product Landscape Life Cycle Assessment Approach to Evaluating Local Climate Mitigation Potential,” in the June 20 issue of the Journal of Cleaner Production†
“The concept of sustainable agricultural intensification has been applied to more large-scale landscape applications,” said one of the paper’s co-authors, Hoyoung Kwon, one of the principal environmental scientists in Argonne’s Energy Systems and Infrastructure Analysis (ESIA) division. “We looked at productivity and GHG emissions, sought to optimize land management tactics and products, and explored various tradeoffs that improve land and land productivity.”
For example, farmers can clean up crop residues of maize (or “stealer”) and reuse it for biofuel, but a percentage of the stove can remain in the soil for valuable nutrients and carbon sources for future crops. Farmers can plant ground covers during the winter (or “fallow”), as a supplement to removed stove. The authors took into account energy, which incurs emissions costs for ground cover planting, to holistically address the net benefits of stew pear removal and ground cover planting. Farmers can also reduce how much land they work after a growing season has ended, which reduces decay and reduces the amount of CO. decreases2 that comes out of the ground. However, the farmer has to work part of the land to be ready for the next growing season.
While some farmers are already following one or even all three of these practices, the scientists at Argonne believe that a better understanding of their impact will motivate more to do so, with real benefit.
“Our approach gives a holistic perspective and looks at the farmer’s perspective: what are all the products that can be produced on the land and what are the sustainability benefits?” said co-author Troy Hawkins, fuels and products group leader in Argonne’s ESIA division. “Agriculture can be a risky exercise with low margins. Profitability will always be a primary focus. However, sustainability has a value that may not be recognized. How can we combine all of that with changes in land management practices to make agriculture more sustainable and improve farm costs ?”
The scientists looked at the tradeoffs and synergies between sustainable intensification and carbon-secured conservation measures in a realistic scenario. They used two models — DayCent and the Greenhouse Gases, Regulated Emissions and Energy Use in Technologies (GREET) LCA — to evaluate an agricultural area upstream from Des Moines, Iowa.
The DayCent model represents the daily flows of carbon, nitrogen and water between the atmosphere, vegetation and soil in natural and agricultural ecosystems. The scientists relied on it to evaluate GHG emissions from corn ethanol production and the effects of harvesting residues.
They used GREET to account for emissions related to agricultural activities and the use of harvested corn kernels, soybeans and corn cobs as feedstock for biofuel production. GREET is widely used in all sectors to evaluate energy consumption, greenhouse gas emissions, air pollutant emissions and water consumption associated with the supply chains of biofuels and other transport and energy technologies. Co-author Michael Wang, Argonne’s interim division director for energy systems and infrastructure, is a primary architect of GREET.
According to the study, harvesting 30% of corn on the cob for biofuel production would increase farm revenues, double net profitability and increase total landscape biofuel production by 17-20%. Removing the stove would also reduce greenhouse gases somewhat, but it reduced the base amount of good carbon in the soil by 40%. In comparison, integrated approaches, including cropping winter cover and/or reducing tillage intensity, would increase soil carbon, improve farm profitability and reduce more greenhouse gases.
“We focused on corn and soy, but our approach could be extended to other crops,” Hawkins said. “Many farms today are large, industrial farms that are high-tech and rely much more on high-resolution data. We want to give farmers, regional planners and others in agricultural management a tool to calculate how to use land sustainably and get the most value from the land. This will promote both profitability and environmental goals.”
Central research uncovers practices, technologies essential for sustainable agriculture
Trung H. Nguyen et al, A Multi-Product Landscape Life Cycle Assessment Approach to Evaluate Local Climate Mitigation Potential, Journal of Cleaner Production (2022). DOI: 10.116/j.jclepro.2022.131691
Quote: Can farms maximize production while reducing greenhouse gas emissions? (2022, June 17) retrieved June 17, 2022 from https://phys.org/news/2022-06-farms-max-greenhouse-gas-emissions.html
This document is copyrighted. Other than fair dealing for personal study or research, nothing may be reproduced without written permission. The content is provided for informational purposes only.