Opportunities to increase soil carbon sequestration in grazing lands in the southeastern United States

Abstract

BackgroundGrazing lands provide numerous ecosystem services, including the capacity to store large amounts of soil carbon (C); however, our understanding of the factors affecting soil C responses to management is inadequate.MethodsIn this paper, we synthesized information about the impacts of grazing land management on soil C within the southeastern region of the United States.ResultsMost studies (68%) demonstrated that proper management increased soil C stocks with an average C accumulation rate of 1.4 Mg C ha−1 year−1. The remaining (32%) studies showed no effect of management on soil C. None of the studies reported negative impacts of management on soil C. The largest increase in soil C (8 Mg C ha−1 year−1) was associated with the conversion of cropland to pastureland while overseeding legumes into grass pastures resulted in the lowest C sequestration rates (0.2 Mg C ha−1 year−1).ConclusionsConsidering the rates of soil C accretion and the extensive area occupied by grazing lands, data in this synthesis confirm that the adoption of improved management practices can increase soil C sequestration in the southeastern United States. In addition, because most improved management practices can also have co‐benefits, they may be favorable for forage and livestock production and other ecosystem services.

Introduction to the XXV International Grassland Congress virtual special issue

“…In a grassland ecology thematic session, grasslands exemplified the delivery of ecosystem services, including the capacity to store large reservoirs of soil organic carbon. One paper in this special section synthesized available literature on soil organic carbon changes with long-term grassland management in the southeastern United States (Silveira et al, 2024) and another paper presented new results of an unique calculation method to separate pedogenic from management-controlled soil organic carbon and nitrogen changes with long-term pasture management (Franzluebbers et al, 2023). In a grazing intensity experiment, the hypothesis that patches will lead to greater spatial variability in belowground biomass and soil organic carbon stocks was not validated (Komainda et al, 2023).…”