Model Description

The Frontiers model is a simple model of the carbon (C), nitrogen (N), and phosphorus (P) cycles in a Douglas-fir (Pseudotsuga menziesii) forest. The model can be run in four configurations that differ in resource uptake by plants and microbes. The four configurations are: (1) Uncoupled: The C cycle is independent of the N and P cycles. (2) Liebig:  The growth rate for plants and microbes is constrained only by the most limiting of the resources needed for growth, respectively. (3) Concurrent limitation: The growth rate for plants and microbes is limited by all resources at the same time. (4) Acclimating: Plants and microbes can adjust their capacity to acquire each resource, optimizing the relative proportions of the resources taken up to achieve maximum growth. The full model equations are available as a supplement to the journal article on the Frontiers in Ecology and Environment web site (

Download the model

The Frontiers model is written in Borland Delphi 2007. The model executable provided has been tested under Windows 2000 and XP. It should run under Windows Vista and Windows 7 without modification. However, its stability under all conditions cannot be guaranteed.  The user assumes all risk for its use.

The model is provided as a zip file.  Place the zip file in an empty directory and uncompress it. Included in the download are the windows executable, sample parameter and driver files, and instructions for running the model.

Downloading and using the software requires that:

1) The Principal Investigator of the model be sent a copy of reports or manuscripts based on the model prior to submission and be adequately cited in any resultant publications.

2) A copy of any resultant publications should be sent to:

Edward Rastetter
Ecosystems Center
Marine Biological Laboratory
Woods Hole, MA 02543

Agree and download

Rastetter, E. B. 2011. Modeling Coupled Biogeochemical Cycles. Frontiers in Ecology and the Environment 9:68-73.

This material is based upon work supported by the National Science Foundation under grant DEB 0716067 (OPUS). Any opinions, findings, conclusions, or recommendations expressed in the material are those of the author and do not necessarily reflect the views of the National Science Foundation.