SAC 623 REMOTE SENSING AND GIS TECHNIQUES, SOIL AND CROP STUDEIS

Lecture 8 Geographic Information System (GIS) Geographic information system (GIS) is defined as a powerful set of computer-based tools for collecting storing, retrieving at will, and transforming and-displaying spatial him from the real world for a particular set of purposes. GIS consists of (i) An extensive database of geographic information involving both positional data about land features and descriptive / non-locational data about these features at different points of time; and (ii) Sets of programmes of applications, which enable the data to be input, assessed, manipulated, analyzed and reported.           The GIS history dates back 1960 where computer based GIS have been used and their manual procedures were in life 100 years earlier or so. On introduction of and spread of personal computers in 1980’s, exponential growth of GIS technology took place. However, potentiality of GIS is realized in the recent past and now it ...

Lecture 7 Definition of Aerial Photograph  The aerial photography is defined as the science of making photographs from aircrafts for studying the earth’s surface.  Aerial photographs of the earth’s surface are taken using a variety of platforms like balloons, rockets, aircrafts, satellites etc. Aria! photography was the first method of remote sensing and even today in the age of the satellite and electronic scanners, aerial photographs still remain the most widely used type of remotely sensed data. The popularity of aerial photographs is due to its six characteristics namely, Characteristics of Good Aerial Photographs  1.      Availability: Aerial photographs are readily available at a range of scales for much of the world. 2.      Economy: Aerial photographs are Cheaper than field surveys and are often cheaper and more accurate than the maps for many countries of the world.  3.   ...