This section walks the user through a tutorial highlighting the basics of the geospatial software package QGIS and includes a list of vector and raster data downloads. The current most stable version of this program is QGIS 3.16. QGIS is an open source software package and is available to download at:
A view of the window is shown below. To download a version, simply click on the relevant platform, and click the download link, highlighted in blue.
The link will open up a new tab in your Internet browser which will then download to your downloads folder. Locating the download (which should start ‘QGIS-OSGeo’) and double clicking on it should open up an installer wizard that will guide you through the steps of installing the software.
Once installed, an icon should appear on your desktop (or be locatable from the ‘Start’ search bar for Windows users), similar to that shown.
When you launch QGIS, you should see a similar setup to that shown below:
|MENU||Provides access to all the functions and plugins|
|TOOLBAR||Provides one-click common functions|
|LAYER LIST||Shows all data layers currently added to the project|
|MAP VIEW||Provides a dynamic visualization of the active data layers that can be mapped|
|STATUS BAR||Provides some vital information about the current project settings|
|These tools allow the user to move about in the ‘Map View’, zooming in and out and zooming to the spatial extent.|
|A tip if you ‘lose’ the data in the ‘Map View’ is to right click on the layer in ‘Layer List’ and go to ‘Zoom to layer extent’.|
If an icon is not visible in the toolbar you may need to go to ‘View’, Toolbars’ and select the necessary toolbar.
Else, the icon may require a specific plugin. To view available plugins, go to ‘Plugins’ and then to ‘Manage Plugins…’.
The resulting dialogue box allows the user to select the features needed.
QGIS has a ‘Help’ function on the toolbar; help can be also found extensively on the Internet though forums and examples.
Before adding data, the project should be saved by navigating to ‘File’ > ‘Save As’.
Saved projects have a ‘.qgs’ or ‘.qgz’ file extension and display the QGIS file icon. It is advisable to save regularly.
Vector and Raster Data Sources
|UK Government Data – Find Open Data https://data.gov.uk||Find data published by central government, local authorities and public bodies to help you build products and services. Contains data from Natural England, Environment Agency, and Forestry Commssion.||Available for commercial and non-commercial reuse under the Open Government Licence. https://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/|
|DEFRA https://magic.defra.gov.uk/Dataset_Download_Summary.htm||The MAGIC website provides authoritative geographic information about the natural environment from across government. The information covers rural, urban, coastal and marine environments across Great Britain. It is presented in an interactive map which can be explored using various mapping tools that are included. Natural England manages the service under the direction of a Steering Group who represent the MAGIC partnership organisations.||Some datasets are available for commercial and non-commercial reuse under the Open Government Licence. https://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/ |
Other datasets are licensed under a Public Sector Mapping Agreement End User License, and are not allowed to be used for commercial activities. https://magic.defra.gov.uk/Copyright_Information_Data_Download.htm
|Map Cruzin |
|Free GIS Shapefiles, Software, Resources and Geography Maps|
|Natural Earth |
|Natural Earth is a public domain map dataset available at 1:10m, 1:50m, and 1:110 million scales. Featuring tightly integrated vector and raster data, with Natural Earth you can make a variety of visually pleasing, well-crafted maps with cartography or GIS software.||All versions of Natural Earth raster + vector map data found on this website are in the public domain, and can be used for commercial and non-commercial use. https://www.naturalearthdata.com/about/terms-of-use/|
|Food and Agriculture Organisation of the United Nations (FAO) |
|FAOSTAT provides free access to food and agriculture data for over 245 countries and territories and covers all FAO regional groupings |
from 1961 to the most recent year available.
|Available for commercial and non-commercial reuse under the Creative Commons 3.0 Intergovernmental Organization (IGO) license. http://www.fao.org/3/ca7570en/ca7570en.pdf|
|The most comprehensive maps and geospatial data available in UK Higher and Further Education||Higher education data services|
|Natural Environment Research Council (NERC) https://data-search.nerc.ac.uk/geonetwork/srv/eng/catalog.search#/home||The DCS allows you to seach a catalogue of metadata (infomration describing data) to discover and gain access to NERC’s data holdings and information products. The metadata are prepared to a common NERC Metadata Standard and are provided to the catalogu by the NERC Data Centre.||https://nerc.ukri.org/research/sites/environmental-data-service-eds/policy/|
|British Oceanographic Data Centre https://www.bodc.ac.uk/data/||The British Oceanographic Data Centre (BODC) is a national facility for looking after and distributing data concerning the marine environment. They handle biological, chemical, physical and geophysical data and their databanks contain measurements of nearly 22,000 different oceanographic variables.||https://nerc.ukri.org/research/sites/environmental-data-service-eds/policy/|
|UK Centre for Ecology and Hydrology https://www.ceh.ac.uk/data||The long-term environmental data hosted by the UK Centre for Ecology & Hydrology (UKCEH) make a difference, informing research, policy-making, commercial innovation and conservation action all around the world. They are committed to making the data available for others to use.|
|ICUN Red List of Threatened Species https://www.iucnredlist.org/resources/spatial-data-download||The IUCN Red List of Threatened Species™ contains global assessments for almost 134,400 species. More than 82% of these (>111,000 species) have spatial data. The spatial data provided below are mostly for comprehensively assessed taxonomic groups and selected freshwater groups. It is important to note that some species (such as those listed as Data Deficient) are not mapped and subspecies, varieties and subpopulations are mapped within the parental species.||https://www.iucnredlist.org/terms/terms-of-use|
|National Biodiversity Gateway https://registry.nbnatlas.org/datasets||Much of the content in the NBN Atlas, such as occurrence records, environmental data, images and the conservation status of species, comes from data sets provided by collecting institutions, individual collectors and community groups.||Datasets can be filltered by license type for commercial and non-commercial use.|
|USGS Emergency Operations https://www.usgs.gov/core-science-systems/hdds||USGS Emergency Response strives to ensure that the disaster response community has rapid access to timely, accurate, and relevant geospatial imagery, products, and services before, during, and after a disaster.||https://www.usgs.gov/core-science-systems/hdds/data-policy|
|Diva GIS |
|Free Spatial Data (country level, global level, global slimate data, species occurrence data, crop collection data, 90m elevation data)||https://www.diva-gis.org/about|
|NASA’s Earth Science Data Systems (ESDS) program oversees the life cycle of NASA’s Earth science data—from acquisition through processing and distribution. The primary goal of ESDS is to maximize the scientific return from NASA’s missions and experiments for research and applied scientists, decision makers, and society at large.||NASA’s data policy ensures that all NASA data are available fully, openly, and without restrictions. https://earthdata.nasa.gov/collaborate/open-data-services-and-software|
|The USGS EarthExplorer provides search and order capabilities for satellite images, aerial photography, and cartographic products. Users may register for a USGS account vie the “Register” link on the EarthExplorer main page.||https://www.usgs.gov/policies-and-notices|
|Copernicus Open Access Hub https://scihub.copernicus.eu/dhus/#/home||The Copernicus Open Access Hub (previously known as Sentinels Scientific Data Hub) provides complete, free and open access to Sentinel-1, Sentinel-2, Sentinel-3 and Sentinel-5P user products, starting from the In-Orbit Commissioning Review (IOCR).||https://scihub.copernicus.eu/twiki/do/view/SciHubWebPortal/TermsConditions|
Downloading Free Ordnance Survey Data
To download free Ordnance Survey data go to:
The Ordnance Survey provides a range of free data including maps from 1:10,000 to 1:250,000. This example uses ‘OS VectorMap District’ data, which is provided in vector data type in either ESRI shapefile or GML format.
The data can be downloaded in a simple 5 step process:
- Select Set a custom area
- Click on the desired Nation Grid Reference Square (e.g. ‘SH’).
- When you have selected all the data you wish to download, select the ‘Save Selection’ button.
- Change the Data Format to ESRI Shapefile.
- Then click the download link to download the file.
This section covers how to import vector data, change the style of a vector layer and select features by attribute and location.
Importing Vector Data Into QGIS
Open QGIS from the desktop icon or by searching for ‘QGIS’ in Applications.
|To import vector data click on the ‘Add Vector Layer’ icon highlighted in red.|
|Locate the required vector data within the ‘Add Vector Layer’ dialogue box by clicking on the |
‘Browse’ button ensuring he ‘Source Type’ is set as ‘File’. Click ‘Open’.
|Layers can be turned off so that they are invisible by un-ticking the box next to the layer name |
in the ‘Layers List’. The order in which layers are displayed an also be changed. Left-click and hold
a layer within the ‘Layers’ column to drag it up or down the list.
|QGIS works with both vector and raster data. Raster data is made up of a regular grid of cells. |
All the cells are the same size and each one contains a unique data value.
|Vector data exists as points, lines or polygons. A vector layer can have many point, line and polygon objects. |
Each vector object within a vector layer has unique information associated with it. All this information is stored
within an attribute table. Each vector object has its own row within the attribute table.
Note: Right-click on a layer in the ‘Layers List’ and scroll to ‘Open Attribute Table’ to be able to view this information.
Changing The Style Of A Vector Layer
Changing the colour and/or outline of a vector layer is an important step in making visually effective maps. Although some downloaded layers may import with a standard colour scheme, often you may wish to change the colours to match your objective.
|Figure 1: To open the layer properties, right click on the vector layer within the ‘Layers List’ and go down to ‘Properties’ on the dropdown menu.|
|Figure 2: Within the ‘Layer Properties’ dialogue box, click on the ‘Symbology’ tab.|
|Figure 3: To change the colour fill of the shapefile click on second indented ‘Simple fill’ under the symbol selection at the top of the box and then click on the ‘Fill Color’ box to open the ‘Select Color’ dialogue box.|
|Figure 4: Within the ‘Select Fill Color’ dialogue box, move the cursor to choose an appropriate colour for the layer. When selected, click OK in the ‘Select Colour’ dialogue box and then ‘OK’ in the ‘Layer Properties’ box.|
The layer will have now changed colour.
Selecting And Querying Vector Layers
Tip: It is recommended to only visualise layers that are needed in the current processing step. This decreases the time taken to visualise the data after changes.
From the menu of the main user interface, the ‘Identify Features’ icon may be used to query a layer. To use this function, click on the layer to query within the ‘Layers List’, then click on the ‘Identify Features’ icon. Within the ‘Map View’ click on the feature to be identified, to bring up the ‘Identify Results’ box.
Tip: Vector layers are also known as shapefiles and have a ‘.shp’ file extension.
Tip: When viewing information with multiple shapefiles, drag the polygon files to the bottom of the ‘Layer List’ so that they don’t cover the point or line files.
Querying A Vector Layer
Features can also be selected from a layer by creating a query expression. To clear a selection use the ‘Deselect Features from All Layers’ icon located on the main toolbar.
|To select a feature by it’s attributes, open the attribute table by right clicking on the desired layer within the ‘Layers List’ and scrolling down to ‘Open Attribute Table’ on the dropdown menu.|
|Click on the ‘Select features using an expression’ icon at the top of the attribute table to bring up the ‘Select By Expression’ dialogue box.|
|Within the ‘Function List’ under ‘Fields and Values’ select the desired field to sort by. To load the values to be selected click on the button ‘All Unique’. To add a value to the ‘Expression’, double click on the value and it will appear in the expression box. The example in Figure 4 is selecting the road numbered ‘A4086’ from the field ‘ROADNUMBER’. Use the operators to define the expression (i.e., ‘Is equal to’). Click ‘Select Features’when the expression is finished then click ‘Close’.|
|To see the selection in the attribute table, toggle ‘Show All Features’ and change to ‘Show Selected Features’. To be able to see your selection in a closer view, click on the icon ‘Zoom map to the selected rows’ in the attribute table (highlighted in red). To return to a view of the full extent, click the ‘Zoom Full’ icon on the top toolbar.|
Tip: Mistakes can easily be made when creating an SQL expression. Try re-entering the expression if the ‘Invalid’ sign appears.
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