Relationships of priming effects with organic amendment composition and soil microbial properties

Soil organic carbon (SOC) sequestration through the application of amendments (OAs) is considered an important strategy to offset anthropogenic CO2 emissions while simultaneously enhancing soil quality and food security. The efficiency SOC sequestration, however, depends on priming effect which influenced by interactions OA composition with microbial response variables (MRVs). Yet, there remain large uncertainties surrounding mechanisms relationships defining these interactions, hampering identification OAs most effective for hindering inclusion dynamics in models. In this study therefore, we performed integrated assessment a cropland amended wood chips, waterway residues, isotopically enriched road-verge grasses, compost, bokashi. Changes 11 properties effects (for labelled OAs) were monitored 150 days related 22 characterizations composition. We demonstrate that i) hot water extractable total ratios are superior predictors effects, ii) dissolvable hot-water closely variation MRV expressions, iii) correlate significantly changes several MRVs. Findings advocate adoption energetic principles modelling predicting microbially-mediated suggest high concentrations – potentially achievable composting, but not fermenting, prior can allow more efficient sequestration.