Introducing GIS^worksheets

Understanding what GIS is and what it can be used for. With a GIS application you can open digital maps on your computer, create new spatial information to add to a map, create printed maps customised to your needs and perform spatial analysis. In this worksheet we explore the basic concepts behind Geographical Information Systems.

Understanding of vector data models as used in GIS. Vector data provide a way to represent real world features within the GIS environment. A feature is anything you can see on the landscape such as houses, roads, trees, rivers, and so on. Each one of these things would be a feature when we represent them in a GIS Application. Vector features have attributes, which consist of text or numerical information that describes the feature. In this worksheet we expore the different geometry types used to represent vectors.

Understanding the role of attribute data in a GIS. Attribute data describe features. Attribute data can help us to make interesting and informative maps, and perform spatial analysis in a GIS application. In this topic we describe how attribute data are associated with vector features and can be used to symbolise data.

Learn how to create and edit vector and attribute data. In the previous two topics we looked at vector data. We saw that there are two key concepts to vector data, namely: geometry and attributes. The geometry of a vector feature describes its shape and position, while the attributes of a vector feature describe its properties (colour, size, age etc.). In this section we will look more closely at the process of creating and editing vector data – both the geometry and attributes of vector features.

Discover the different kinds of raster data and how they can be used in a GIS. Raster data are arranged in a matrix of cells. Each cell in the matrix has a value. When viewed as a whole the raster looks like an image. In this worksheet we take a closer look at raster data.

Topology defines the relationship between vector features. In this topic we look at how topology is used in a GIS, and the differences between topological and non topological datasets. We also look at how topological concepts can be used to improve the digitising process.

Coordinate Reference Systems (CRS) provide a system for specifying location. In this topic we explore why CRS are needed and look more closely at the advantages and disadvantages of different CRSes.

Understanding map production for spatial data. Map production is the process of arranging map elements on a sheet of paper in a way, that even without many words a layperson understands what it is all about. Maps are very often produced for presentations and reports where the audience or reader is a politician, citizen or a learner with no professional background in GIS. Because of this, map has to be most effective in communicating spatial information. In this worksheet we explore the common elements of a map and how they can be combined to produce a pleasing product.

Understand the use of buffering in vector spatial analysis. Spatial analysis uses spatial information to extract new and additional meaning. Usually spatial analysis is carried out using a GIS Application. A GIS provides normally has spatial analysis tools for feature statistics (e.g. how many vertices make up this polyline?) or geoprocessing such as feature buffering (e.g. which area falls within a certain distance of this feature?). In this worksheet we look more closely at vector analysis, using buffering as an example.

Understand interpolation as part of spatial analysis. Spatial interpolation is the process of using points with known values to estimate values at other unknown points. In this worksheet we describe interpolation in more detail and give some examples of how it can be useful.

Now that we have given you a basic tour of what you can do with a GIS Application, its time to learn and discover for yourself. The QGIS User Guide contains descriptions of all of the key parts of QGIS. When you are not sure of how to do something, e.g. adding a new layer, use the index in front of the guide to find the correct page and you will find step-by-step directions.

If you want to print all the above worksheets as a single book or classroom resource, we provide that for you here. Print this out and then append the QGIS manual from item 11 above for a complete classroom resource.

Updated 22 Oct 2009:We are also providing an editible version of the complete document in OpenOffice document format. Use the pdf if you want it in print ready format and the odt if you want to edit it in OpenOffice. Please remember that the license permits you to modify and repurpose these materials but you may not remove the attribution / copyright (front pages) or the license (back pages). We encourage you to contribute any changes and improvements you have made back to use so that others may benifit from your work - just as you have from our work!

The sample data is provided with the customised QGIS installer that we have provided to the right of this page. However if you are using Linux or prefer to use a more current version of QGIS, you can use the data provided here as a separate 11mb zip file.