This paper contains information about the geographic information system (GIS)-hardware- software-human-computer complex, which provides fee, handling, displaying and circulating spatial data, data integration and knowledge about terrain for their effective use at decision scientific and applied geographical tasks, relating to analyzing, modeling, forecasting and control of the ambient environment. Geoinformation system contains data about spatial entities, combined in a collection of covers and makes information models of data domain, operation set, which define system functionality and realize GIS technologies software, apparatus and information. GIS prognostic (indicator and estimate) covers display natural phenomena, potentially contain forecast capabilities of their evolution and play the key role in the decision support system. Space photos or remote sensing data, which contain information on natural environment and allow us to allot particular entities and their border, are base data source for special covers in GIS. Below we reveal one of the thematic maps generation methods for a decision support system through the use of instrument environment ERDAS Imagine (ERDAS Inc., Atlanta, Georgia), for environment handling and remote sensing data use.