ELOGeo for Beginners

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Welcome to the digital repository of the ELOGeo Project. This is a digital service that collects, preserves, and distributes digital material about open geospatial data, software and standards, in order to facilitate the digital preservation and scholarly communication in the open geospatial community.

More information are also available at ELOGeo project website

Contents

Introduction for Beginners

If you have no prior experience of GIS, we would suggest that you start from the GIS for Educators series

Topic 1: Introducing GIS

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.

Topic 2: Vector Data

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.

Topic 3: Vector Attribute Data

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.

Topic 4: Data Capture

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.

Topic 5: Raster Data

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.

Topic 6: Topology

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.

Topic 7: Coordinate Reference Systems

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.

Topic 8: Map Production

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.

Topic 9: Vector Spatial Analysis (Buffers)

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.

Topic 10: Spatial Analysis (Interpolation)

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

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