Cover crop impacts on US cropland carbon sequestration

Excerpt

Cover crop management can sequester soil carbon (C), but the potential of cover crops to do so across the United States has not been clearly quantified. With concern about the rising levels of carbon dioxide (CO₂) in the earth's atmosphere, solutions that sequester atmospheric CO₂ are being sought. The soil has significant potential to store C (Batjes 1996), and the potential contribution of agricultural practices like cover crops to sequestering C in the soil is of particular interest to farmers, scientists, and policy-makers across the globe (Lal 2015).

Though several studies have shown the ability of cover crops to sequester C on experimental plots and across the globe (Franzluebbers 2010; Lal 2015; Lal et al. 1998; Poeplau and Don 2015; Ruis and Blanco-Canqui 2017), research is still needed that addresses the regional and national impact cover crops can have on C sequestration across cropland in the United States. The United States surpassed 4 × 10⁶ ha (10 × 10⁶ ac) of cover crops in 2012, and farmers are projected to plant 8.1 × 10⁶ ha (20 × 10⁶ ac) or more of cover crops by 2020 (USDA 2014; CTIC 2016). This publication summarizes the results of a literature review and…