Olson's Major World Ecosystem Complexes Ranked by Carbon in Live Vegetation: A Database (CDIAC NDP-017)

Olson's Major World Ecosystem Complexes Ranked by Carbon in Live Vegetation is a computerized database, used to generate a global vegetation map of 44 different land ecosystem complexes (mosaics of vegetation or landscapes) comprising seven broad groups. The map is derived from patterns of preagricultural vegetation, modern areal surveys, and intensive biomass data from research sites. Work on the database was begun in 1960 and completed in 1980.

Ecosystem complexes are defined for each 0.5-degree grid cell, reflecting the major climatic, topographic, and land-use patterns. Numeric codes are assigned to each vegetation type. Classifications include natural as well as human managed/modified complexes such as mainly cropped, residential, commercial, and park. The complexes are ranked by estimated organic carbon in the mass of live plants given in units of kilograms of carbon per square meter. Counting the cells of each type and adding their areas give total area estimates for the ecosystem complexes. Multiplying by carbon estimates gives corresponding estimates of global carbon by ecosystem complex. The results help define the role of the terrestrial biosphere in the global carbon cycle.

The data are available for downloading from the Carbon Dioxide Information Analysis Center (CDIAC). NDP-017 includes the following data and documentation files:

1. Original matrix data file (latitude, longitude, and ecosystem code)
2. Compressed flat data file (ndp017_g.dat.Z) of latitude, longitude, ecosystem code, ecosystem complex name, gridcell area, and carbon densities (medium, revised medium, minimum, and maximum)
3. Ascii metadata file
4. Ascii documentation file
5. FORTRAN input code for the original matrix data file
6. Global ecosystem map, in both gif (world.gif) and postscript (worl.ps) formats
7. Table providing information on ecosystem types and carbon densities (medium, revised medium, minimum, and maximum)
8. Compressed ARC/INFO export file (olson-carbon.e00.Z) for geographic information system (GIS) users
9. Ascii documentation file (ndp017gis.doc) for GIS data
10. Global carbon map in gif format (med_carbon.gif)
11. Ascii text file including SAS and FORTRAN code used to create ndp017_g.dat.Z

Recommendations for the use of the data as well as more detailed information can be found in: Olson, J.S., J.A. Watts, and L.J. Allison. 1983. Carbon in Live Vegetation of Major World Ecosystems. ORNL-5862, ESD Pub No. 1997, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA.