Modeling and simulating biogeochemical cycles: the BCS freeware

The use of simulation is a scientifically-recognized way of studying biogeochemical cycles, mainly when consecutive disturbances are made. As a pedagogical tool, simulation helps students gain insight into the response dynamics of the respective biogeochemical cycle. The development of simulation tools for educational purposes has not progressed much for the last couple of decades, despite advances in computer science. Trying to fill in that gap, this paper presents the biogeochemical cycles simulator (BCS) freeware, a more user-friendly replacement for older simulators. The BCS is a light-weight, user-friendly, Windows®-based simulator. Using the sulfur biogeochemical cycle as an example, the simulation results from two sequential disturbances were compared with those of the former tools: the sum of relative errors between the three tools was never greater than 2.7%. Moreover, a real-world event (Mount Pinatubo’s Eruption 1991) was also simulated, giving similar results to those actually measured. The major improvements made include: a friendly graphical user interface, unlimited number of reservoirs, direct input of mass fluxes, multi-disturbance assessment, and fully customizable plots. The BCS freeware has been used in case studies, in a biogeochemical cycles course of a B.S. in Chemistry at the University of São Paulo, Brazil. Simulations helped students to develop decision-making and group-working skills, as well as enhanced data interpretation. Moreover, the students were able to recognize how even small disturbances can cause short- and long-term impacts on biogeochemical cycles. A set of possible strategies for using BCS as an educational tool is also provided in this work.