An approach to the biometeorology of decomposer organisms

Abstract

A search for surrogate variables of weather's control over rate of decay by decomposer organisms has revealed that Actual Evapotranspiration (AE), a water budget term, correlates well (r = 0.976) with measured values of litter decomposition rate. Using data from many biomes of the earth, a curve-fit of AE with measured decomposition rate has been formulated. This curve-fit has been used to prepare a map which displays the geography of predicted decay rate for North America. The physical properties of the litter also controls decomposition rates. Work is in progress to refine the AE to decomposer relationship by considering the lignin content of decomposing litter. Preliminary results suggest that control of decomposition rates by lignin increases with AE so that in high AE environments small changes in lignin concentration result in large changes in litter decay rates. This relationship perhaps explains the great variability in decay rates reported in tropical ecosystems.