Applying an oxygen-based respiratory assay to assess soil microbial responses to substrate and N availability

摘要: Abstract Documented approaches for measuring soil microbial activities and their controlling factors under field conditions are needed to advance understanding of processes numerous applications. We manipulated plots with carbon (C) nitrogen (N) additions test the capability a respiratory assay to: (1) measure respiration endogenous C in comparison field-measured CO 2 fluxes; (2) determine substrate-induced (SIR) that consistent substrate availability field; and, (3) report N based on responses without added N. The utilizes microplate containing an oxygen-sensitive fluorescent ruthenium dye. Respiratory measured this approach have previously been shown occur within short (6–8 h) incubation periods using low concentrations minimize enrichment during assay. Field treatments were conducted randomized full-factorial design (casamino acids, glucose, or none) inorganic (±) as treatment factors. With one exception, we found responded similar manner fluxes field. Patterns SIR amino acid carbohydrate (200 μg C g −1 soil) treatments. ratio (N ) (25 μg N g same was significantly ( P exhibited logarithmic relationship r  = 0.64, situ examine limit these activities.