Substrate-induced respiration in Puerto Rican soils: minimum glucose amendment
Soil microbiota –usually quantified as microbial biomass –is a key component of terrestrial ecosystems, regulating nutrient cycling and organic matter turnover. Among the several methods developed for estimating soil microbial biomass, Substrate-Induced Respiration (SIR) is considered reliable and easy to implement; once the maximum respiratory response is determined for a particular substrate amendment and study area. We determined the minimum glucose amendment of three forest types in Puerto Rico: dry, moist, and wet subtropical forests. The minimum glucose concentration was 3 mg C-glu/g dry soil for these forests. Additionally, we discuss soil properties to be considered for the implementation of SIR in tropical soils.