A research program for and the process of building and testing grassland ecosystem models

Highlight: This paper reports on the organization and operation of the U.S. International Biological Program ‘s Grassland Biome study. The study has involved in the past 8 years a large number of scientists from many disciplines working in an integrated and data-sharing mode. Field studies have been conducted on 11 western grassland sites to obtain data to drive and to validate mathematical simulation models and to provide cross-site comparative information. The models are based upon data from field studies, the literature, and rate process studies, often conducted in the laboratory. A multiple-flow, ecosystem level model called “‘ELM” which can be adapted to various sites by changing parameters is described. The types and sources of scien tific outputs from the program are described.