Scientists from the USGS and the environmental services company Envu completed the first comprehensive study evaluating the relationship of soil carbon to exotic annual grass invasion and wildfire—disturbances that degrade over one million acres of sagebrush shrublands annually. Researchers measured total carbon in samples from three sagebrush-steppe ecoregions in the western U.S. They found that invasion and wildfire reduced soil carbon by approximately 50%, which could amount to 17-20 teragrams of carbon loss annually. The results confirmed that disturbances can affect deep soils just as strongly as shallow soils, and that incorporating deep soil measurements is important for estimating carbon losses. Dryland soils can store a massive amount of carbon and help keep greenhouses gases out of the atmosphere. This study suggests that maintaining intact sagebrush-steppe by protecting against the annual grass-fire cycle could be an effective “nature-based” carbon storage strategy. The journal article was accompanied by a news release and a "Behind the Paper" blog post by Matt Germino. 

Maxwell, T.M., Quicke, H.E., Price, S.J., and Germino, M.J., 2024, Invasive grass-fire cycle depletes ecosystem carbon storage by >50%, to resistant base levels: Nature Communications, Earth & Environment, v. 5, no. 669. https://doi.org/10.1038/s43247-024-01795-9