GLOBAL SOIL DATA BASES FOR ENVIRONMENTAL MODELING 
Norman B. Bliss, Principal Scientist, Hughes STX Corporation, EROS Data Center, Sioux Falls, 
South Dakota, USA (work performed under U.S. Geological Survey contract 1434-92-C-40004), 
ISPRS Commission VII 
Understanding global processes requires integrating information on physical, chemical, and biological 
processes at a variety of spatial and temporal scales. Many of these processes depend on or interact 
with the world's body of soils--the pedosphere. Soil maps provide a stratification of the landscape 
designed to separate major elements based on observable soil properties. Traditionally, soil scientists 
have made their stratifications sensitive to agricultural productivity, but other ecological processes 
are now considered. Carbon storage in soils is an indicator of fertility and also a source or sink for 
atmospheric carbon dioxide or methane, which influences greenhouse gas concentrations. The dynamics of 
soil moisture is significant, not just for crop survival, but as a component of general circulation 
models of the atmosphere. The existing data bases of soil distribution and properties can provide 
valuable information for these additional interpretations. A key link is a soil taxonomic system that 
can account for the physical and chemical properties that vary within seasons, such as soil moisture and 
soil temperature regimes. Global soil data bases at mapping scales of 1:30,000,000 and 1:5,000,000 have 
been developed that include attribute files of soil properties by taxonomic class. The data bases are 
used to produce interpretive maps and data sets relevant to interdisciplinary global change research. 
Key Words: Global, Soil, Data Base, Carbon, Moisture 
112