There are mainly four key activities that any urban planners or scientists orresource managers and others use geographic information for. They observe and measure environmental parameters and develop maps which portray characteristics of the earth.
GEOGRAPHIC INFORMATION SYSTEM
There are mainly four key activities that any urban planners or scientists orresource managers and others use geographic information for. They observe and measure environmental parameters and develop maps which portray characteristics of the earth. They monitor changes in our surroundings in space and time. In addition, they model alternatives of actions and process operation in the environment. These, four activities are Measurement, Mapping, Monitoring and Modelling termed as key activities which can be enhanced by the using information systems.
Fig 4.3 Map Analysis
GIS technology is more different from traditional mapping and map analysis.GIS is based on a mathematical framework of primitive map analysis operations analogous to those of traditional statistics and algebra. From this perspective, GIS forms a toolbox for processing maps and fundamental concepts for spatial measurement. It provides a foundation for advanced analytic operations involving spatial analysis and measurement. Most of GISs contain analytic capabilities for reclassifying and overlaying maps. Any GIS system for the measurement of areas, distances, angles and so on requires two components, namely, a standard measurement unit and a measurement procedure. Another major function of GIS capability is the study of environmental surroundings and the monitoring of environmental parameters (Burrough et ai, 1988). Although analytical models have been linked to GIS for spatial measurement and resource assessment, the cross fertilisation between the modules of modelling, measurement and automated mapping allows the GIS user to monitor the environment· and the earth system. In principle, it is possible to make a clear distinction between GIS and digital cartography. Mapping technology or digital cartography deals with map features and with associated attributes of colour, symbology, name of annotation, legends, neatlinesand north arrows. GIS includes the capabilities for storing, editing, and handling the relationships of attributes with their spatial entities along with the capabilities of digital cartography. A map, an ultimate product of digital cartography or GIS, is a very persuasive form of data display and a computer drawn map carries the authority of a powerful technology. GIS applications now span a wide range, from sophisticated analysis and modelling of spatial data to simple inventory and management. They also dictate the development directions of much of the industry. However, several vendors have chosen to concentrate on the niche market for environmental applications and to emphasise support for environmental modelling. GRASS is a Significant public domain GIS software developed by USA with substantial capabilities for modelling.