Decomposition is responsible for the largest fluxes of carbon dioxide to the atmosphere and provides the largest source of nutrients to plants. Therefore, understanding decomposition patterns is critical in ecological and biogeochemical studies. Ecological stoichiometry theories predict that the relations among elements during decomposition should follow specific trajectories that depend on the type of material that is decomposed and the properties of the decomposer community. One key prediction is that such relations should be invariant across terrestrial-aquatic boundaries. Using worldwide published data and mathematical models we are testing this hypothesis and its implications on global biogeochemical cycles.