|
/
/
/
About MRC Mapping
Introduction
to MRC mapping
Zooming in and out
Available Information:
Health Facilities
Schools
Population 2001
Household Services
Buffering
Search
Information tool
Map Layers
Search
Tool bar
Map sizing
Metadata
Basic GIS concepts
Introduction
to MRC mapping
MRC
Mapping, developed jointly by the Health
GIS Centre, Malaria Research
Programme and Intermap, is
aimed at providing the user with useful information in a mapped format,
so that simple queries, searches and printing can be undertaken. This
application is not intended to replace the services provided by the Health
GIS Centre, but rather run as a parallel facility, with the Centre continuing
to undertake joint collaborations with specific projects.    
The
map can be viewed at varying magnitudes by zooming in and out. These
images show how different information is available at varying zoom levels.
EG Roads and rivers are only visible when zoomed in to 150km ( see Map
Layers for details on zoom levels)
Zooming
in and out
Zooming in
and out refers to changing the scale of the map and therefore the amount
of detail you can see. In the first map above, where the whole of south
Africa is displayed, the zoom scale is set at 1960.411km, which means
that the distance across the screen reflects 1960km on the ground. There
are three different ways of zooming in and out: 1.
Using the Zoom in tool
This allows
you to click and draw a box around the area which you would like to get
more detail on. 2.
Using the Zoom to button 
This allows
you to specify the zoom distance across the map OR if you have a latitude
and longitude reading of an area you would like to zoom in on.
3.
Using the Click to Zoom button
This option allows you to choose your required zoom distance from
the drop-down list and then click to zoom. Hint: this is a useful way
of returning to the map of the whole country. Remember that if you
zoom in too far or at the incorrect place, you can always use the Zoom
Undo button. 
You
will notice that as you zoom further and further in, more layers become
visible. This is to ensure that the map does not become too cluttered.
You do however have the option of going to 
where you can turn different layers on and off.
4. Using the Zoom out tool  Zooming
out is a little bit more tricky than zooming in. Select the zoom out
tool and click once in the centre of the map; this doubles your zoom,
for e.g. if the zoom was 630km and you zoom out once, the resulting
zoom will be 1260 km zooming out
Available
Information
The buttons on the left of the screen list the "layers" of available
information which you can choose to include on your map ( ie turn "on”
and “off”). You can display:
- the
different types of health facilities and
schools
- the
population category of each magisterial district
- pie
graphs for each municipality in a selected province showing the
proportion of households with access to water,
electricity and sanitation
- the
enumerator areas in a selected province
- buffers
can be drawn around either health facilities or schools in a selected
district council
 Health
facilities
Please
remember to check the meta-data for the health facilities carefully
before using the data, as the provinces have very different levels of
accuracy.
First zoom in to the area required.
Click on 
You will see this sub menu:
First select a province (or National), then select the type of facility
you want to add to the map. (Note that the “Uncoded” facilities apply
only in Gauteng).
Once you go  a
legend for the facilities you switched on will appear in a new window.
Click 
to remove all health facilities from the map.
 Schools
First
zoom in to the area where you wish to display schools.
Click 
First select
a province (or National), then select the type of school.
Once you go a
legend for the schools you switched on will appear in a new window.
Click 
to remove all schools from the map.
Population
 The
user can display a thematic map of population per municipality using
the 2001 census data.
Alternatively,
to see the population of a specificmunicipality or enumerator area,
zoom in to the area of interest and use the information
tool 
Household
Services:
electricity, water, sanitation
Click
on the service you would like displayed ie water, electricity or sanitation.Select
a province, then click “apply pie chart”. Pie graphs will be displayed
for each municipality in the selected province showing the proportion
of households with access to the different categories of this service.The
1996 census data has been used and grouped according to municipality
( source: Municipal Demarcation Board) These pie graphs are only available
at certain zoom levels and are best viewed at province level or below.
However, if you zoom below 300km, they will disappear. Note:The
map legend appears in a separate window.
Buffering
1. Turn
on the features that you would like to buffer i.e. schools or health facilities
(optional) 2.
Select the Buffer Tool 
 3.
Select Buffer Type and Province to Buffer
4. Click
Apply Buffer and the following options will appear: Specify a District
Council from the drop-down list.
Choose a buffer colour from the drop-down list as well as the distance
of the required buffers, in kilometers. Once you have selected your options,
click on Apply Buffer. Remember that all features in the selected
layer (health facilities or schools) will be buffered even if only one
category ( eg clinics) is turned on.
Information
Information
on household services and population is available for each enumerator
area and each municipality - Note: if the layer is not "visible"
and in the right order, you will not get the information you require. 1.
For information by enumerator area: Turn
on the ea's by clicking the ea button
You may need to turn off roads and rivers to reduce clutter ( Click on
map layers and then deselect roads and rivers )Click on the information
tool Click
on the enumerator area for which you want information 2.
For info by municipality:Turn
off the district council layer ( click on map layers; deselect district
councils)Click on the information tool Click
on the municipality for which you want information ToolBar
Pan tool: Recentre the map by dragging it.
Zoom
in tool:
Zoom
out tool:
Information
tool:
 Measuring
tool: Click on two points to measure the straight line distance between
them.
 Pin
tool: Adds a pin image to the selected point on the map.
 Label
tool: Turns labels on or off. (This can also be done in the Layer
Control window)
 Print
tool: Displays a print preview window and allows the user to add a map
title.
Map
Layers
 The
layer control window/ box displays the available layers or features that
have been turned on, whether their labels are 'on' and at what scale /
zoom level they are visible at..Each layer can be made visible or invisible
here but can only be turned on/off using the theme buttons Eg 1 towns
will be shown on the map when the user has zoomed lower than 200km.EG
2 Rivers can be turned off by clicking the visible box next to rivers Provinces
and their labels are only visible when the map is at full view ie entire
country is displayed.
Search
The search facility allows the user to search for a health
facility, school or town and then locate it on the map. It is a wildcard
search so the search will yield all results approximating the search
item entered.
Map
Sizing
Click
on the Map Sizing button and a new window called Map Settings will open.
This gives you the option to increase or decrease the map width and
height in pixels (note: the default width is 586 pixels and height 330
pixels).
Meta
Data 
This
is where you will find information about the data on this site, such
as the source and date. It is important to read this section (particularly
for health facilities) before using the data to make decisions.
GIS
Concepts
Although
this application is not a true GIS, we have provided a few basic GIS
concepts and definitions as well as a list of useful links for those
wanting obtain more information on the various GIS issues.
What
is GIS?:
There
are many definitions of GIS: According to Bailey and Gatrell (1995,
in Moore and Carpenter, 1999) “a GIS is an integrated set of computer
hardware and software tools to capture, store, edit, analyse, and display
spatially referenced data.” Clarke et al (1996) continue by stating
that; “common to all GIS is the realisation that spatial data are unique
because their records can be linked to a geographic map”.
Scale:
refers to the relationship between distance on the map and distance
on the ground. The scale affects the amount of detail that is visible
and therefore has implications for the type of analysis that can be
done.
Layers:
the different types of map features (roads, rivers, health facilities
etc) are stored in different layers so that they can be opened separately.
Data of the same type are kept in separate layers.
Points,
lines and polygons:
points are a single set of co-ordinates (e.g. a health facility), lines
are a series of joined co-ordinates (e.g. roads) and polygons are areas
bounded by lines.
Overlay:
since data of different types is kept in different layers it can be
overlaid on top of each other. Overlaying data-sets allows users to
interrogate the relationships between them, for e.g. by overlaying the
health facilities and roads gives an idea of accessibility.
Buffering:
refers to a drawing circle or zone of influence around either a
point, line or polygon.
Thematic
map: is
a map showing selected kinds of information relating to one or more
specific themes. Examples are population distribution and rainfall maps.
Further
Reading:
http://www.usgs.gov/research/gis/title.html
http://www.sli.unimelb.edu.au/gisweb/GISModule/GISTheory.htm
http://www.cdc.gov/nchs/gis.htm
http://www.geo.ed.ac.uk/agidict/alpha.html
|
