1. General Model Information

Name: grassland and agroecosystem dynamics model

Acronym: CENTURY

Main medium: terrestrial
Main subject: biogeochemistry, agriculture
Organization level: ecosystem
Type of model: ordinary differential equations
Main application: research
Keywords: grassland, agroecosystem, dynamics, nitrogen, carbon, phosphor, sulfur, nutrient cycle, capacity cascade model


William J. Parton,
Dennis S. Ojima,
Dave Schimel
Rebecca McKeown,
Cindy Keough,
Melannie D. Hartman,
Becky Techau

Colorado State University
email: century@nrel.colostate.edu
Homepage: http://www.nrel.colostate.edu/projects/century/



Century is a simulation and process model used to understand grassland and agroecosystem dynamics. Other versions exist for savannas and forests. The purpose of the model is to analyze soil organic matter dynamics in response to changes in management and climate. The model uses monthly time steps for simulations of up to several thousand years to examine the flows of carbon, nitrogen and phosphorus.

Data required for input are:

The output contains information on carbon and nitrogen fluxes, net primary production and soil organic matter. The spatial extent of the model is regional with most executions at the 1m2 resolution.

Global change implications: The model has been used extensively for global change research. The model has been executed in over 22 different areas in the world (Bill Parton, personal communication). It can be used to assess the impacts of regional climate change on a variety of important grassland ecosystems. It has also been coupled to vegetation growth models (Laurenroth et al., 1993) such as STEPPE.

II. Technical Information

II.1 Executables:

Operating System(s): DOS, Unix Download Page

II.2 Source-code:

Programming Language(s): FORTRAN and C
see: Download Page

II.3 Manuals:


II.4 Data:

see workbook

III. Mathematical Information

III.1 Mathematics

III.2 Quantities

III.2.1 Input

View Input data requirements of CENTURY in comparison to other Soil Organic Matter models:
These seven tables can be downloaded in Postscript Format

III.2.2 Output

View output data of CENTURY in comparison to other SOM - Models:

IV. References

Parton W.J, Schimel D.S., Cole C.V., Ojima D.S.: Analysis of factors controlling soil organic matter levels in Great Plains Grasslands. Soil Sience Society, 1173 - 1179, 1987.
Parton W.J., McKoewn B., Kirchner V., Ojima D.: User Manual for the CENTURY model. 1992.
Parton W.J., Stewart J.W.B., Cole C.V.: Dynamics of C, N, P and S in grassland soils : a model. Biogeochemistry, 109 - 131, 1988.
Parton W.J., Brown V.B., Singer M.J.: Predicting nitrogen leaching in an annual grassland. Bulletin of the Ecological Society of America, 178, 1993.
Parton W.J., Seastedt T.R., Ojima D.S.: Mass loss and nitrogen dynamics of decaying litter of grasslands: the apparent low nitrogen immobilization potential of root detritus. Canadian Journal of Botany, 384 - 391, 1991.
Parton W.J., Singh J.S.: Adapting a biomass simulation model to a tropical Grassland. Ecological Modelling, 151 - 163, 1993.
Parton W.J., Pulliam W.M., Ojima D.S.: Application of the CENTURY model across the LTR network: Parameterization and climate change simulations. Bulletin of the Ecological Society of America (75), 186 - 187, 1994.
Parton W.J., Ojima D.S., Schimel D.S., Owensby C.E.: Long - and short term effects of fire on nitrogen cycling in tallgrass prairie. Biogeochemistry (Dordrecht), (24,2), 67 - 84, 1994.
Parton W.J., Rassmussen P.E.: Long - term effects of crop mangement in wheat - fallow : II. CENTURY model simulations. Soil Science Society of America Journal, 58(2), 530 - 536, 1994.
Parton W.J., Rassmussen P.E.: Long term effects of residue management in wheat - fallow : I. Inputs, yield, and soil organic matter. Soil Science Society of America Journal, 58(2), 523 - 530, 1994.
Parton W.J., Scott, Ojima D.S., McKane R., Neal A., Rastetter E.B.:Carbon storage in terrestrial ecosystems: A comparison of the CENTURY and GEM ecosystem simulation model. Bulletin of the ecological society of America, 73, 340, 1992.
Parton W.J., Ojima D.S., Schimel D.S., Kittel T.G.F.: Modelling the effects of climatic and CO2 changes on grassland storage of soil C. Water, Air and Soil Pollution, 70, 643 - 657, 1993.
Parton W.J., Cole C.V., Paustian K., Elliott E.T., Metherell A.K., Ojima D.S.: Analysis of agroecosystem carbon pools. Water, Air and Soil Pollution, 70(1-4), 357 - 371, 1993.
Parton W.J., Lauenroth W.K., Urban D.L., Coffin D.P., Shugart H.H., Kirchner T.B., Smith T.M.: Modelling vegetation structure - ecosystem process interactions across sites and ecosystems. Ecological Modelling, 67(1), 49 - 80, 1993.
Parton W.S., Ojima D.S., Owensby C.E., Coyne P.I: Simulation of carbon and nitrogen dynamics under elevated carbon dioxide in the tallgrass prairie. Bulletin of the Ecological Society of America, 73, 290 - 291, 1992.
Parton W.J., Ojima D.S., Seastedt T.R.: Integrating the influence of community dynamics on ecosystem properties relative to changes in environmental factors. Bulletin of the Ecological Society of America, 72, 209, 1991.
Parton W.J., Agren G.I., McMurtrie R.E., Pastor J., Shugart H.H.: State-of-the-art of models of production - decomposition linkages in conifer and grassland ecosystems. Ecological Applications, 1(2), 118 - 138, 1991.
Parton W.J., Paustian K., Persson J.: Model analysis of soil organic matter dynamics in log - term agricultural field plot. Bulletin of the Ecological Society of America, 71, 281, 1990.
Parton W.J., Innis G.S., Hanson J.D.: Plant growth and production of grassland ecosystems, a comparison of modelling approaches. Ecological Modelling, 29(1-4),131 - 144, 1985.
Parton W.J.: Predicting soil temperatures in a shortgrass steppe. Soil Science, 138(2), 93 - 101, 1984.
Parton W:J., Coughenour M.B., Lauenroth W.K., Dodd J.L., Woodmansee R.G: Simulation of a grassland sulfur cycle with appendices. Ecological Modelling, 9(3), 179 - 214, 1980.
Parton W.J., Singh J.S., Coleman D.C.: A model of production and turnover of roots in a shortgrass prairie. Journal of Applied Ecology, 15(2), 515 - 524, 1978.
Sitompul, S.M.; Hairiah, K.; Noordwijk, M. van; Woomer, P.L.; 1996. Organic matter dynamics after conversion of forests to food crops or sugarcane: predictions of the CENTURY model. Special issue: biological management of soil fertility for sustainable agriculture on an ultisol.Agrivita. 1996, 19: 4, 198-206; 22 ref..
Laurenroth, W.K., D.L. Urban, D.P. Coffin, W.J. Parton,H.H. Shugart, T.B. Kirchner and T.M. Smith. 1993. Modeling vegetation structure--ecosystem processinteractions across sites and ecosystems. Ecol. Mod. 67:49-80.

V. Further information in the World-Wide-Web