RESOURCE-ALLOCATION TO EXTRACELLULAR ENZYME-PRODUCTION - A MODEL FOR NITROGEN AND PHOSPHORUS CONTROL OF LITTER DECOMPOSITION

Most models for plant litter decomposition link degradation rates to measures of climate or litter composition, rather than directly to microbial activity. We developed a model based on the premise that saprotrophic microbial communities maximize their productivity by optimizing their allocation of resources in the production of extracellular carbon, nitrogen and phosphorus-acquiring enzymes. In this model, enzyme activity indicators are used to estimate decomposition rates and to assess relative N and P availability. This approach may facilitate estimation of decomposition rates in the field and improve ecological forecasting.