Introduction to Geographic Information Systems

Educators

The National Spatial Information Framework

• Functions– Implement the SA Spatial Data Infrastructure

Act (SASDI)• Promote use, sharing & access to spatial

information through:– Coordination – Committee for Spatial Information– Setting standards – ISO, SANS– Regulations – SDI Act Regulations– Infrastructure – Spatial Metadata Discovery (SMD)– Awareness – Exhibitions, Seminars, Workshops

The National Curriculum Statement: Geography

Learning Outcomes &

Assessment Standards

Geographic Skills & Tools:Map reading; Maps; GIS

Geography Content:Population; Settlement; Climate

The National Curriculum Statement: Geography

AnalyseAnalyse

OrganiseOrganise

IssueIssue

QuestionQuestion

PlanPlan

CollectCollect

ReportReport

Problem solving/Problem solving/scientific research scientific research

approachapproach

What is GIS?

• Information system that – integrates – stores– edits– analyzes– shares– displays geographic information

GIS Components

GIS

People Software

Data

ProceduresHardware

Why GIS?

• Spatial information (location) + descriptive or attribute data within a single system

• Make connections between activities

• Convert data to spatial information and display geographically

• Make better decisions, quicker

GIS: As Decision Enabling

ActionAction

DecideDecide

ObserveObserve

MeasureMeasure

AnalyzeAnalyze

PlanPlan

. . . a Framework For Action

Inte

grat

e

GIS Applications• Population• Bio-Diversity• Global Warming• Urbanization• Pollution• Congestion• Conservation• Land Use• Oceans• Business Efficiency• Water• Development

• Crime• Health• Education• Logistics• Energy• Defense / Security• Environment• Government• Globalization• Agriculture/Food• Public Safety

Land Reform

Agricultural: Crop type mapping

Urban Growth225 New Townhouses (2000 -2002)

Housing - Alexander

0

50

100

150

200

50 year 100 year RMF

Informal

formal

Water

Water & Health

Education

390 500 / 441 484 learners live

within 3 km of Secondary

Schools

Stormwater Infrastructure Mapping and Modeling

Why GIS in Geography

• What is Geography?– a science that studies physical and human

processes, the interactions between the two and spatial patterns over space and time.

• GIS - uses spatial data & non-spatial data to generate new spatial information

GIS & Geography • Questions Geographers AskQuestions Geographers Ask

• Where is it located?

• Why is it located there?

• How and why are places different?

• How do people interact with their environment?

• The answers to these questions is spatial data The answers to these questions is spatial data which is an input in a GISwhich is an input in a GIS

Basic Concepts in GIS

• Map

generalized and reduced representation of

(a portion of) the curved surface of the earth

on a flat surface

Map with map elements

• Spatial data

Feature that can be linked to a particular

location on the earth

Geometry - Point

Attribute – 117; 1000m

above sea-level

POLYGONSLINESPOINT POLYGONSLINESPOINT

DATA REPRESENTATION

• Remote Sensing

Aerial Photograph

Satellite Image

• Resolution

Detail with which a map/image depicts the

geographic features

Higher resolution = more details

Low resolution = less details

The smallest unit of information in an image

or raster map, usually square or rectangular

Pixel

This example shows an image with an enlarged portion, in which the individual pixels appear aslittle squares and can easily be seen.

Co-ordinate System

• Geographic– uses latitude and

longitude

• Projected/ Cartesian– uses measurements

along x-axis and y-axis

Reference framework that is used to define

the positions of points in space in either two

or three dimensions

+10Y

+290X

Geographic & Projected Coordinate Systems

• Projection

A method of converting the curved earth

surface into a flat surface.

Choice of projection based on:

Geographic location of area mapped

Purpose of the map

Scale of the map

Map Projections

Geographic location of area mapped

ConicalCylindrical/ Transverse

Planar

Projections on SA National Maps

Lambert’s Conformal Conic

1: 500 000 Maps

Gauss Conformal

1:10 000 Orthophoto Map & 1: 50 000

Topographic map

Albers Equal Area

1: 2 000 000 Map

1:10 000 Orthophoto map

1: 50 000Topographic Map (2329CD)

• Global Positioning System

A system of orbiting satellites used for

determining positions on the earth

Handheld GPS

Constellation of Satellites

A Satellite

Survey GPS

• Database

Information organised in an easily

retrievable manner – a filing systemEMIS_NO SCHOOL TOWN SCHOOL

TYPEWALL TYPE

ROOFTYPE

WATER

0106322385 ENCOTSHENI KHAYALITSHA PRIMARY BRICK ZINC YES

0105001047 HOUT BAY HOUT BAY COMBINED PREFAB ZINC YES

0103310307 TABLE VIEW CAPE TOWN SECONDARY BRICK TILES NO

Row: Record – with a distinct record number

Column: Field – with a distinct field name

Practice

• Refer to 4.2; Page 20 of the workbook– Map to use: South Africa Protected Areas;

Page 14.

A GIS Project

• Typical project process

ActionAction

DecideDecide

Question/Question/ProblemProblem

CollectCollect

OrganizeOrganize

AnalyzeAnalyze

The Project Problem

• Situation that prompts action

• Geographic problem must always be related to location.

• Examples:– Where is the best location for a school?– What is the relationship between climate and

vegetation?

Extract on Poverty

“South Africa has a poverty problem”. The 2005 United Nations Human Development Report records that 10.7% or 5 million people in South Africa survive on less than R6.50 per day. South Africa ranks 56 out of 103 in the world poverty rankings with a Human Poverty Index of 30.9%, that’s 14.5 million people”.

“Poverty is apparent to the human eye and is profiled by shacks, homelessness, unemployment, casualised labour, poor infrastructure and lack of access to basic services”.

“Enough is enough.  South Africa must act now”.

Project Problem

• What is the problem?

Which areas of South Africa have the highest poverty?

• What is the project question?

High poverty

Defining poverty

• Lack of proper shelter

• No safe drinking water

• No proper sanitation, etc

Project Requirements

• Identify area with the highest poverty

– No proper sanitation

– Lack of proper housing – informal houses

– No access to water

– High unemployment rate

What are you required to do?

Data Acquisition/ Collection• Types of data

Statistics

Remote Sensing

Fieldwork

Maps

What data do we need for the Poverty Project?

Project Requirements

Data needed Where to find the data?

Housing StatsSA

Access to water Dept. Water

StatsSA/ Dept. ofWaterSanitation

Dept. of TransportRoads

No proper houses

No tap water

Orientation data

No proper sanitation

Practice – Using MapWindow

Open newproject

Empty project

Mapwindow

Menus Bar

Toolbar: with Several Tools

1. Open Project

2. Save 3. Identifier 4. Measuring Tool

21 43

Add Layer

Data Folders

Add Data

Mapwindow: Adding Data

Data Folders

Add Layer

MapWindow: Using the legend

Check in box

Close MapWindow

Data Processing

• It may be necessary to process the data - making the data suitable for use in the specific project

Examples:

Scanning map/images, digitising, image rectification,

geo-referencing, changing projection, correcting errors (e.g.

over/undershoot, edge matching), removing unwanted

information, changing scale, generalisation, classifying and

integrating of information.

1st - Create a new project

Data ProcessingAttribute table icon

Data ProcessingGIS Tools

Data Analysis

– Querying• selecting information from a GIS by asking questions

of the geographic data by location or attribute information.

• Different methods of analysing data

– Spatial Analysis• Extracting or creating new information about a set of

geographic features and examining the relationships between them.

– Buffering• Creating an area of specified width or distance from

an object such as a point, line or polygon.

Practice: Data analysis

• Querying Information– Identifying features:

• What is at?• Where is it? E.g. Where are secondary schools?

• Let us make a few queries in MapWindow

Querying: Identifier

Identifier button

Querying: Identify by Shape

Querying:

Buffering

Creating an area of specified width or distance from an object such as a point, line orpolygon

Spatial Analysis

Extracting or creating new information

Spatial AnalysisCombining Different Attribute Files

Querying the new data

Export selected features

Gauteng Poverty Map

Product Generation

• This is about communicating the results

– Map, Graphs

– Printing / Web

– In terms of maps, consider the following:• Map design features – e.g. scale, projection,

symbology, colours.• Map elements – e.g. map title, north arrow, legend,

scale, citations.

Practice on your own

• Section E:– Your school has been asked by your District

municipality to assist the Major by identifying high level poverty stricken areas within your district municipality. Use a GIS to identify the poverty stricken areas in your district municipality.

Thank you

Contacts