NCERT Book Class 12 Geography Spatial Information Technology

Spatial Information Technology

You know that the computers enhance our capabilities in data processing and in drawing graphs, diagrams and maps (Refer Chapter 4 of the present book). The disciplines that deals with the principles and methods of data processing and mapping using a combination of computer hardware and the application software are referred as the Database Management System (DBMS) and the Computer– Assisted Cartography respectively. However, the role of such computer applications is restricted to merely processing of the data and their graphical presentation. In other words, the data so processed or the maps and diagrams so prepared could not be used to evolve a decision support system.

As a matter of fact, there are several questions that we normally encounter in our day-to-day life and look for satisfactory solutions. These questions may be : What is where ? Why is it there ? What will happen if it is shifted to a new location ? Who will be benefited by such a reallocation? Who are expected to loose the benefits if reallocation takes place? In order to, understand these and many other questions we need to capture the necessary data collected from different  sources and integrate them using a computer that is supported by geo–processingtools. Herein lays the concept of a Spatial Information System. In the presentchapter, we will discuss basic principles of the Spatial Information Technology and its extension to the Spatial Information System, which is more commonly known as Geographical Information System.

What is Spatial Information Technology? 

The word spatial is derived from space. It refers to the features and the phenomena distributed over a geographically definable space, thus, having physically measurable dimensions. We know that most data that are used today have spatial components (location), such as an address of a municipal facility, or the boundaries of an agricultural holdings, etc. Hence, the Spatial Information Technology relates to the use of the technological inputs in collecting, storing, retrieving, displaying, manipulating, managing and analysing the spatial information. It is an amalgamation of Remote Sensing, GPS, GIS, Digital Cartography, and Database Management Systems.

What is GIS (Geographical Information System)?

The advance computing systems available since mid 1970’s enable the processing of georeferenced information for the purpose of organising spatial and attribute data and their integration; locating specific information in individual files and executing the computations, performing analysis and evolving a decision support system. A system capable of all such functions is called Geographic Information System (GIS). It is defined as A system for capturing, storing, checking, integrating, manipulating, analysing and displaying data, which are spatially referenced to the Earth. This is normally considered to involve a spatially referenced computer database and appropriate applications software. It is an amalgamation of Computer Assisted Cartography and Database Management System and draws conceptual and methodological strength from both spatial and allied sciences such as Computer Science, Statistics, Cartography, Remote Sensing, Database Technology, Geography, Geology, Hydrology, Agriculture, Resource Management, Environmental Science, and Public Administration.

Excercises

1. Choose the right answer from the four alternatives given below :

(i) The spatial data are characterised by the following forms of appearance :

    (a) Positional

    (b) Linear

    (c) Areal

    (d) All the above forms

(ii) Which one of the following operations requires analysis module software?

    (a) Data storage

    (b) Data display

    (c) Data output

    (d) Buffering

(iii) Which one of the following is disadvantage of Raster data format ?

    (a) Simple data structure

    (b) Easy and efficient overlaying

    (c) Compatible with remote sensing imagery

    (d) Difficult network analysis

(iv) Which one of the following is an advantage of Vector data format ?

    (a) Complex data structure

    (b) Difficult overlay operations

    (c) Lack of compatibility with remote sensing data

    (d) Compact data structure

(v) Urban change detection is effectively undertaken in GIS core using:

    (a) Overlay operations

    (b) Proximity analysis

    (c) Network analysis

    (d) Buffering

2. Answer the following questions in about 30 words :

   (i) Differentiate between raster and vector data models.

   (ii) What is an overlay analysis?

   (iii) What are the advantages of GIS over manual methods?

   (iv) What are important components of GIS?

   (v) What are different ways in which spatial data is built in GIS core?

   (vi) What is Spatial Information Technology?

3. Answer the following questions in about 125 words :

   (i) Discuss raster and vector data formats. Give example.

   (ii) Write an explanatory account of the sequence of activities involved in GIS related work.

Please refer to attached file for NCERT Class 12 Geography Spatial Information Technology