Abstract Grassland degradation reduces net primary production and, subsequently, soil fertility and soil organic carbon stocks (SOCs); however, little is known about its impact on soil CO2 emissions, particularly the emissions relative to SOCs and biomass produced. The main objective of this study, performed in KwaZulu-Natal province of South Africa, was to quantify the impact of grass basal cover, as main indicator of grassland degradation, on soil CO2 emissions. The soil CO2 emissions were measured from three grass cover levels (non-degraded, with 100% grass cover; moderately degraded: 25