Data from: Thermodynamic constraints on the utility of ecological stoichiometry for explaining global biogeochemical patterns

Carbon and nitrogen cycles are coupled through both stoichiometric
requirements for microbial biomass and dissimilatory metabolic processes
in which microbes catalyse reduction-oxidation reactions. Here, we
integrate stoichiometric theory and thermodynamic principles to explain
the commonly observed trade-off between high nitrate and high organic
carbon concentrations, and the even stronger trade-off between high
nitrate and high ammonium concentrations, across a wide range of aquatic
ecosystems. Our results suggest these relationships are the emergent
properties of both microbial biomass stoichiometry and the availability of
terminal electron acceptors. Because elements with multiple oxidation
states (i.e. nitrogen, manganese, iron and sulphur) serve as both
nutrients and sources of chemical energy in reduced environments, both
assimilative demand and dissimilatory uses determine their concentrations
across broad spatial gradients. Conceptual and quantitative models that
integrate rather than independently examine thermodynamic, stoichiometric
and evolutionary controls on biogeochemical cycling are essential for
understanding local to global biogeochemical patterns.