introduction to gis for the purpose of practising pgis
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Introduction to GIS for the Purpose of Practising PGIS. Introduction to GIS. By: Jon Corbett and Kasondra White. Unit: M12U01. Introduction. Participatory GIS (PGIS) Documenting, presenting and protecting local knowledge What is a GIS? Representing data Quantum GIS - PowerPoint PPT PresentationTRANSCRIPT
Support the spread of “good practice” in generating, managing, analysing and communicating spatial information
Introduction to GIS for the Purpose of Practising PGIS
Introduction to GIS
By: Jon Corbett and Kasondra White
Unit: M12U01
Introduction
• Participatory GIS (PGIS)
• Documenting, presenting and protecting local knowledge
• What is a GIS?
• Representing data
• Quantum GIS
• Participatory mapping and GIS
What is a GIS?
• GIS systems:– capture;– store;– analyse;– manage; and– present geographic data.
What is a GIS?
• GIS packages work with:– maps;– remote sensing;– land surveying;– aerial photography;– databases;– other tools.
What is a GIS?
• GIS applications allow users to:– create queries;– analyse spatial information;– edit data and maps;– present results.
• Information can be presented:– in a map;– in a textual form.
What is a GIS?
• Geospatial data:– information related to a location that can be
expressed using coordinates
• GIS can be used for:– creating maps– visualising the relationship between places
and events– searching for geospatial associations– analysing geospatial data
Representing data
• Kinds of questions that GIS can answer:– What is located at a given point?– What kinds of changes have occurred?– What kinds of patterns exist?– What would happen if some kind of a change
were to occur?
Points, lines and polygons• Points
– one spot on a map
– represent exact locations
• Lines
– string of points
– can be measured
for distance
• Polygons
– enclosed area
– defined by often
complex boundaries
Data layers
• Features are displayed through data layers
• Contain thematic data
• Layers can be:– turned on or off– placed on top of or below
one another
• Multiple layers can be open at one time
Quantum GIS
• Open source – freely available– supported by a community of programmers
and technicians
• User-friendly
The graphical user interface (GUI)
• Simplifying interactions with software
• Uses:– clickable symbols– text
• Understanding GUI functions is an important part of learning GIS
The graphical user interface
The toolbar
Participatory mapping and GIS
• Does GIS fit with the community’s vision?
• Does GIS directly address mapping needs?
• Is GIS anti-participatory?– expertise required– may require technicians from outside the
community
Participatory mapping and GIS
• Practitioners of participatory development should avoid technologies that are:– complex– expensive– time-consuming
• May, however, still be useful
• “Chauffeur-driven” systems
GPS• Displays points collected through a
Global Positioning System (GPS)• Captures coordinates of locations
of interest• Points can be uploaded and
displayed• Useful for depicting locations or
boundaries