Constraint-based simulation of multiple interactive elemental cycles in biogeochemical systems

Abstract

Simulating multiple linked elemental cycles is a frontier in the field of biogeochemistry. The Generalized Algorithm for Nutrient, Growth, Stoichiometric and Thermodynamic Analysis (GANGSTA) is a software framework that automates the instantiation of formalized, user-defined conceptual models of linked elemental cycles as simulation model code. The GANGSTA employs first principles of stoichiometry and thermodynamics to generate models that simulate any suite of elemental cycles, compounds, metabolic processes, and microorganisms. Results demonstrated, e.g., that simulating the oxygen (O) cycle, rather than oxic versus anoxic conditions, fundamentally altered carbon (C) and nitrogen (N) cycling - despite holding the compounds and processes involved in the C and N cycles constant. Additionally, incorporating the sulfur (S) cycle substantively changed C and N cycling, largely via shifts in the O cycle. Thus, emergent dynamics from GANGSTA-derived models can aid in the development of hypotheses to describe the specific mechanisms of interdependence among linked elemental cycles.