Microbial response time to sugar and amino acid additions to soil

摘要: Abstract Soil microbial respiration is derived predominantly from the turnover of carbohydrates and proteins in soil. In most agricultural ecosystems, these C compounds enter soil mainly rhizodeposition (root exudation turnover). Our aim was to determine how long it takes for population reach their maximum mineralization potential after addition low-molecular-weight (MW) rhizodeposits We added sugar form glucose amino acids glycine an arable, grazed grassland, Eucalyptus forest boreal monitored CO 2 efflux over a 6-h period. Artificial rainwater amended (zero addition) or unamended soils were used as controls. The Michaelis–Menten substrate utilization profiles showed vastly different patterns capacity affinity between soils. However, all we that activation community occurred almost instantaneously (⩽60 s) with average time taken half maximal production being 14±8 min 10±8 min glycine. After reaching potential, rate evolution remained constant remainder experiment. results while uptake within biomass activated quickly, subsequent adaptation upregulation its processing did not occur at least short term. fast use partially attribute large degree functional redundancy exists rhizodeposits.