CENTURY Soil Organic Matter Model: Introduction

The CENTURY version 5 agroecosystem model is a soil organic model originally developed by Parton et al. (1987). This model simulates C, N, P, S, and soil water dynamics in a grassland, crop, forest or savanna over time scales of decades to millennia. The producer submodel may be a grassland/crop, forest or savanna system, with the flexibility of specifying potential primary production curves representing the site-specific plant community. CENTURY was especially developed to deal with a wide range of cropping system rotations and tillage practices for system analysis of the effects of management and global change on productivity and sustainability of agroecosystems. The model is available in monthly and daily time-step versions — Century5 and DayCent5.

Version 4 of the model integrated the effects of climate and soil driving variables and agricultural management to simulate carbon, nitrogen, and water dynamics in the soil-plant system. Simulation of complex agricultural management systems including crop rotations, tillage practices, fertilization, irrigation, grazing, and harvest methods is now possible.

Version 5 includes an arbitrarily layered soil physical structure, and new erosion and deposition submodels. The model code has been rewritten in C++, reorganized, and modified to use platform-independent configuration and output files. The models can perform spatially gridded simulations, with input and output using spatial netCDF files. Gridded simulations can scale from laptops to hundreds of CPUs using MPI.

The CENTURY model embodies our best understanding to date of the biogeochemistry of carbon, nitrogen, phosphorus, and sulphur. The primary purposes of the model are to provide a tool for ecosystem analysis, to test the consistency of data and to evaluate the effect of changes in management and climate on ecosystems. Evolution of the model will continue as our understanding of biogeochemical processes improves. The identification of problem areas where processes are not adequately quantified is key to further developments. Ideally, model application will lead to the identification of needed research and new experimentation to improve understanding.

We value the responses and experiences of our collaborators in using CENTURY and encourage their feedback on problems in the current model formulation, as well as insight and suggestions for future model refinement and enhancement. It would be particularly helpful if users would communicate such feedback informally and where possible share with us documented model applications including manuscripts, papers, procedures, or individual model development.

See Also

Preparing for a Century Simulation
Running a Simulation
Viewing Simulation Results
List of Simulation Examples
List of Standard Sites and Management Schemes