Optimizing cover cropping for carbon sequestration under future climate change scenarios

A major concern for Maryland agriculture is the impact of more frequent and extreme weather patterns on crop productivity and land management. Changes in the intensity and duration of wet conditions are already affecting the operations of farms in Maryland, as well as the strategies of farmers as they grapple with uncertainty in future climate-change scenarios and make important decisions about soil carbon sequestration and carbon markets. 

A study being performed by Drs. Jared Wilmoth and Stephanie Yarwood of the UMD College of Agriculture and Natural Resources theorizes that optimized cover cropping is a potential solution to sequestering more carbon in agricultural soils, which could help to mitigate climate change and make farmlands more resilient to its impact. 

Rye and vetch are frequently used as cover crops in Maryland, and when grown together, they likely have greater potential to increase the amount of carbon fixed in soil. Optimization of winter cover cropping with rye and vetch will be crucial for building resilience to climate change given that Maryland is projected to experience the most extreme changes in temperature and precipitation during the winter months over the next 80 years. However, it remains unclear how the management of these cover crops affects the flow of newly fixed carbon between particulate and mineral-associated forms of soil organic matter, which determines the stability of carbon in agricultural lands under future climate scenarios.

The study’s investigators expect that with the most optimal winter cover-cropping practices, more carbon can be sequestered in Maryland agricultural soils. The overarching goal is to provide new data on the role of cover cropping in sequestering carbon and help producers to predict how much carbon they may be storing under different weather conditions. By closely investigating how newly fixed carbon is incorporated into soil organic matter by cover crops, our work will help establish more optimized cover cropping strategies for farmers to build larger and longer-lasting soil carbon stocks.