Soil mineral assemblage and substrate quality effects on microbial priming

Native soil organic carbon (SOC) decomposition rates may be altered through increased carbon (C) input, a phenomenon known as SOC priming (Blagodatskaya et al., 2011). Quantifying priming is important because it may modulate long-term SOC storage in ecosystems and therefore C biogeochemical cycling. Priming is positive when more SOC is decomposed or, conversely, negative when less native SOC is decomposed after C amendment (Kuzyakov et al., 2000; Kuzyakov, 2002; Bader and Cheng, 2007). Yet, controls over the direction and magnitude of the priming effect and the consequences for soil C balance remain uncertain (Dijkstra et al., 2013; Liu et al., 2017).