G-Range is a global rangeland model that simulates generalized changes in rangelands through time. Spatial data and a set of parameters that describe plant growth in landscape units combine with computer code representing ecological processes to represent soil nutrient and water dynamics, vegetation growth, fire, and wild and domestic animal offtake. The model is spatial, with areas of the world divided into square cells. Those cells that are rangelands have ecosystem dynamics simulated. A graphical user interface allows users to explore model output.

Our thanks to Dr. Bill Parton, Cindy Keough, and the many others who have contributed to the Century model, for their permission to allow us to draw from Century. Many of the processes incorporated into G-Range are either from Century, or inspired by that model. Inspiration was also drawn from the Savanna Modeling System, authored by Dr. Michael Coughenour.

The graphical user interface that is used with G-Range.