Lee Belbin, August 2019
There are several sources of location data in the ALA's Spatial Portal, some of which are available in other Atlas of Living Australia tools. To make the most of this location information, you need to know the various forms of location data and how each form is accessed.
Types of ‘Location’ Information
There are six types of location data available in the ALA’s Spatial Portal and a subset are available in other ALA portals:
- Darwin Core location terms (https://dwc.tdwg.org/terms/) within the occurrence records in the ALA. These terms allow you to filter records in the Spatial Portal and elsewhere, and search within a downloaded dataset for locations expressed using these terms. More details here.
- Species areas that may be additional to the Darwin Core data. This may be an area defined by a species checklist or an expert distribution for a species.
- Spatial Intersections of the ALA’s occurrence records with the Spatial Portal’s environmental and contextual layers – this is useful for answering the question: what is the area in which a species record occurs?
- The Spatial Portal’s gazetteer. This option can be used to select any named area.
- Google Map services. This is useful if you want to find a location that will be known to Google, but not our gazetteer. For example, if know the address of a location or the name of a business at the location.
- Cross Tabulations. These are like a scatterplots, but the axes of the table are areas, for example, States/Territories (one axis) and Bioregions (e.g., IBRA 7, the second axis) and entries in the table are spatial intersections of these areas.
How Can Location Data Be Used?
The Spatial Portal can be used to answer 2 primary questions:
- Where does this thing occur?
- What things occur in this area?
The first component corresponds to the Spatial Portal's menu option Add to map | Species.
The second question is location-based, and there are more than 15 ways for an area to be defined using the Spatial Portal. Options include digitizing on the map to defining environmental envelopes. Even sets of occurrence records can be transformed into areas using the Spatial Portal's Tools | Points to grid.
Once you have an area defined (remember that “area” can be multiple polygons), you can generate area reports that list what information the ALA has about those areas; an interactive one (Tools | Area report – interactive: See Figure 1) and one that is more comprehensive (and takes longer) and produces a PDF file (Tools | Area report – PDF). A separate case study will be written to cover how to use the area reports, but the type of information reported includes:
- Area in square kilometres
- Number of occurrence records
- Number of species
- Number of endemic species (species where we have records that only occur within the area)
- Number of ‘expert distributions’ intersecting the area
- Number of species checklists that intersect the area
- Number of JournalMap papers that refer to the area
- Number of Australian Gazetteer Placenames in the area
- Number of ‘threatened’, ‘invasive’, migratory and ‘iconic’ species
- Number of algae, amphibians, angiosperms, ‘animals’, arthropods, bacteria, birds, bryophytes, chromista, crustaceans, dicots, ferns, fish, fungi, gymnosperms, insects, mammals, molluscs, monocots, plants, protozoa and reptile species.
Figure 1. Example of an area report