Enhanced conversion of newly-added maize straw to soil microbial biomass C under plastic film mulching and organic manure management

Abstract Management of crop production using plastic film mulching (PFM) has the potential to improve soil health by accelerating nutrient cycling and facilitating stable C pool production; however, a key aspect of this process—microbial immobilization of residue C—is poorly understood, especially under PFM when combined with different fertilization treatments. A 360-day in situ 13 C-tracing technique was used to analyze the contribution and dynamics of microbial biomass C (MBC) to soil organic C (SOC). Following 27-year PFM and four fertilization treatments, 13 C-labelled maize straw residue was applied to micro-plot topsoil in a cultivated maize ( Zea mays L.) field. Over the course of the experiment, MBC content was significantly (P