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Here is a compilation of essays on ‘Geographic Information System (GIS)’ for class 8, 9, 10, 11 and 12. Find paragraphs, long and short essays on ‘GIS’ especially written for school and college students.
Essay on GIS:
Essay Contents:
- Essay on Introduction to GIS
- Essay on the Definition of GIS
- Essay on the Need of GIS
- Essay on the Benefits of GIS
- Essay on the Uses of GIS
- Essay on the Aspects of GIS
- Essay on the Data in GIS
- Essay on the Functions of GIS
- Essay on the Areas of GIS Application
Essay # 1. Introduction to GIS:
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During the 1960s and 1970s new trends emerged in the method of handling and using of spatial data for assessment, planning and monitoring. Spatial data analysis is a multi-disciplinary activity concerning hydrology, water resources, geography, urban planning and earth sciences.
Spatial data sets are frequently heterogeneous, having data on soils, water, rainfall, infiltration, land use, topography, forestry, administrative boundaries, population, etc., and often available at different scales in different coordinate systems at various levels of text maps, charts, ground information, organization, aerial photographs and satellite imagery.
The management and analysis of such large volumes of spatial data require a computer- based system called Geographic Information System (GIS), which can be used for solving complex geographical and hydrogeological problems.
“Every object present on the Earth can be geo-referenced”, is the fundamental key of associating any database to GIS. Here, term ‘database’ is a collection of information about things and their relationship to each other, and ‘geo-referencing’ refers to the location of a layer or coverage in space defined by the co-ordinate referencing system.
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Work on GIS began in late 1950s, but first GIS software came only in late 1970s from the lab of the ESRI. Canada was the pioneer in the development of GIS as a result of innovations dating back to early 1960s. Much of the credit for the early development of GIS goes to Roger Tomilson. Evolution of GIS has transformed and revolutionized the ways in which planners, engineers, managers, etc. conduct the database management and analysis.
A GIS is a computer system capable of capturing, storing, analyzing, and displaying geographically referenced information, that is, data identified according to location (referenced by latitude/longitude information).
Essay # 2. Definition of GIS:
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GIS is defined as a system of computer hardware and software designed to allow users to collect, manage, analyze and retrieve large volumes of spatially referenced data and associate attributes collected from a variety of sources.
The major advantage of GIS is that it is an information system, therefore, the digital database that has been developed at any stage can also be used in the future and any related information can be extracted conveniently and efficiently.
Remote sensing is a powerful tool for the collection of spatial data and GIS is a powerful tool for management and analysis of data required for any land developmental activity.
Essay # 3. Need of GIS:
GIS is needed for the following reasons:
i. Geospatial data are poorly maintained
ii. Maps and statistics are out of date
iii. Data and information
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iv. There is no data retrieval service
v. There is no data sharing
Essay # 4. Benefits of GIS:
i. Geospatial data are better maintained in a standard format
ii. Revision and updating are easier
iii. Geospatial data and information are easier to search, analyze and represent
iv. Geospatial data can be shared and exchanged freely
v. Productivity of the staff is improved and more efficient
vi. Better decisions can be made
Essay # 5. Uses of GIS:
There are several uses of GIS in resources mapping. Some of them are discussed below:
i. Flood Monitoring and Management:
The area inundated by floods can be mapped and monitored effectively with an integrated approach of remote sensing and GIS techniques. In this simulation various GIS tools such as connectivity and neighborhoods can be used to locate the areas to be protected from the flood water by constructing optimum embankment in the affected area.
ii. Groundwater Hydrology:
In groundwater studies, GIS technology is considered useful as it facilitates handling diverse type of data of spatial information e.g., topographic maps, land use maps, geological maps, contour maps of water table and water quality, etc. Use of GIS also offers the flexibility of operation and speedy processing.
Using GIS functions, user-defined images/maps of any basin can be prepared involving several ground water quality parameters, such as total dissolved solids (TDS), chlorides, bicarbonates, etc. along with groundwater maps and it also generates various output images, which may show area of groundwater suitable for drinking, irrigation, and industrial purposes etc.
iii. Wetland Management:
A primary requirement of management and protection of wetlands is to get accurate map and inventory. Any inventory necessarily includes the area and volume of water body, vegetation types, patterns and water movement directions.
Integrated GIS offers a useful tool to carry out this type of inventory because wetland studies are generally conducted for large and relatively inaccessible areas. GIS is well suited to take inputs from remote sensing and to monitor the changes and to take preliminary estimates of the environmental impact.
iv. Forest Management:
The extent of forest cover, changes in forest cover, strategy for forest resource protection and conservation, forest eco-system studies and studies related to forest’s role in climate all can be effectively studied by integrated approach of remote sensing and GIS. Since climate and terrain have significant roles to play for development of forest cover, GIS can be used to establish a relationship between these parameters.
v. Land Use and Land Cover Change Analysis:
GIS supported by remote sensing has proved extremely useful in monitoring the land use and land cover changes as well as to update the existing land use maps. Such land use maps combined with the slope, irrigation facility and soil condition can be overlaid and modeled in GIS to derive an optimal land use plan.
vi. Urban Sprawl Mapping and Monitoring:
GIS also can be used for:
(a) Studying urban growth trends,
(b) Monitoring urban land use,
(c) Planning urban utility and infrastructural facilities,
(d) Urban land use zoning,
(e) Urban environment and its impact assessment,
(f) Urban population estimation,
(g) Studying urban hydrology, and
(h) Developing urban management models.
vii. Land Degradation:
Land degradation by water erosion, sedimentation, and deterioration, of water quality by point and non- point source pollution is a major environment issue. The scope of GIS for soil erosion studies includes not only overlaying exercises but also analyzing the effect of topography, meteorology and environmental factors on erosion.
viii. Watershed Management:
Watershed management and monitoring has been found to be economical and faster with the use of the capabilities of GIS. Erosion and sediment yield from watershed can be assessed using suitable model in raster GIS.
Essay # 6. Aspects of GIS:
Three aspects of GIS:
i. Cartographic aspect:
It focuses on map aspect of GIS. GIS acts as a map processing and display system where each map is represented as a layer in raster or vector format.
ii. Database aspect:
It emphasizes the importance of a well designed and implemented database. A sophisticated database management system (DBMS) is an integral part of the GIS.
iii. Spatial integration aspect:
It emphasizes the spatial analysis capabilities of GIS. It focuses on integrated analysis and modeling.
What Can You Do with GIS?
a. Find what exists at particular locations.
b. Find locations supported by conditions.
c. Find trends of geographic occurrence that have changed or in the process of changing
d. Analyses pattern and spatial relationships that exist between objects of geographic features.
e. Modeling.
Essay # 7. Data in GIS:
Data in GIS can be classified into two categories:
i. Spatial data:
Spatial data are characterized by information about their physical dimensions and geographic locations on the surface of the earth. Maps are used to represent spatial data.
Map conveys:
(a) Positional information (or location) on the surface of the earth.
(b) Spatial relationships such as adjacent to, located within etc.
(c) Measurable quantities such as length, area, altitude, etc.
(d) Type of feature by the use of symbols or colour.
ii. Non-spatial data:
Non-spatial data qualify spatial data. It is quantitative data that describe some aspect of spatial data not specified by its geometry alone.
Data Format in GIS System:
There are two types of spatial data format in GIS system:
(i) Vector Format and
(ii) Raster Format.
i. Vector Format:
Any map feature, the boundary of which is defined by a series of points that join straight lines is called vector.
All geographical phenomenon identified by spatial data can be two dimensional by three main entity types viz points, lines and polygons forming the vector structure.
Points are used for small locations or features e.g. house, police point, tower etc.
Lines are used for linear features e.g. roads, rivers etc.
Polygons are used for closed set of lines and are used to represent geographical zones.
ii. Raster format:
When the feature is defined by a fine mesh of grid cells it is called raster data. Each grid cell is referenced by a row and column number and it contains a number representing the type or value of the attribute being mapped. The size of the grid can vary, and therefore, the spatial resolution of the data is determined by grid size. The higher the level of resolution the greater the detail that can be distinguished on an image.
Layer based approach:
The traditional method of representing the geographic data is through a series of thematic layers. E.g. a map of geology, one for soils, one for cultural features and so on. Layer based approach is used in GIS where data are organized by separate sets of spatial data called as map layer coverage or level.
These layers can be overlaid with each others to show spatial relationships display, manipulation and analyzed individually or in combination with other layers.
Required data sources for GIS:
Spatial data:
Aerial Photograph
Satellite imagery
GPS data
Non-spatial data:
Reports and publications
Tabular data
Map data
Essay # 8. Functions of GIS:
i. Data entry
ii. Display
iii. Database query: (a) Spatial Query (b) Attribute query
iv. Statistics extraction
v. Buffering
vi. Interpolation
vii. Output generation.
Essay # 9. Areas of GIS Application:
i. Urban Planning and design
ii. Watershed management and planning
iii. Planning for sustainable development
iv. Water quality management
v. Transportation planning
vi. Disaster planning
vii. Environmental impact analysis
viii. Locating underground pipes, cables, etc.