A complete list of plant community types (PCTs) is centrally managed by the department in BioNet. It is known as the PCT master list and is rigorously controlled.
Scheduled maintenance and revisions are undertaken to ensure classification remains based on contemporary, best available information.
When there are changes to the PCT master list, or to the geospatial information that defines plant community types, these are managed across all related data and map products in the Integrated BioNet Vegetation Data program.
For more information visit our NSW plant community type classification webpage.
PCT master list release notes
Release notes are published with each update of the PCT master list. Starting from June 2022, the table below provides links to these notes and a log of changes, including changes to the underlying geospatial information.
PCT classification version number
Date of release
Summary of changes
This update was based on the classification of additional BioNet standard floristic survey plot data in eastern NSW coast and tablelands bioregions: NSW North Coast, South East Corner, South East Queensland, Sydney Basin, New England Tableland, Australian Alps and South Eastern Highlands.
This update introduced a plot-based and data-driven quantitative typology for eastern NSW coast and tablelands bioregions, replacing the regionally sourced qualitative PCTs in operation between 2011 and 2022.
Executive custodianship for the NSW vegetation classification hierarchy, including the PCT master list, resides with the Executive Director Science, Economics and Insights.
PCT master list version control
Version protocols are in place to control changes to the PCT master list and the underlying geospatial information defining each plant community type. A number is applied to each version of the list. This version number provides reference to a formal set of plant community type definitions at a point in time. It also provides a reference between the list and its spatial representation in the State Vegetation Type Map.
The version numbering system adopts an open-ended code structure using the format C1.1.
- The letter C denotes ‘classification’, to differentiate from map version codes that apply the prefix ‘M’ in the State Vegetation Type Map.
- A change to the first number means that one or more approved plant community types have been added or removed.
- A change to the second number (only) indicates amendments to the spatial definition of one or more plant community types, but no addition or removal of approved plant community types.
- The version number started at C1.1, representing the PCT master list at June 2022.
Evidence for change
As new information becomes available, we expect to make improvements to the PCT master list and plant community type definitions.
New vegetation surveys are continuously building on the body of available data, particularly as standard floristic survey methods are increasingly applied across New South Wales. We strongly encourage the collection of standard floristic survey plot data as the most efficient and effective method for evaluating the PCT master list and assessing the need for change.
In eastern New South Wales, plant community types are almost all quantitative, meaning they have member plots defined in BioNet. Explicit rule sets are applied to new data to determine relationships to existing quantitative plant community types. New standard floristic survey plot data may be formally classified to support or expand the definition of an existing type, or provide compelling evidence for description of a new one.
In western New South Wales, plant community types are qualitative. We assess them using new standard floristic survey plot data, but apply less explicit methods to determine relationships to existing types. In this region, we rely on the expert synthesis of classification source data, because standardised information, including survey plot data, has uneven, patchy coverage. As a result, new data are assessed using qualitative methods.
Tracking changes to the PCT master list
When a plant community type is superseded, it is no longer in use and is termed ‘decommissioned’. Decommissioned types stay visible in the BioNet Vegetation Classification application and web services. Relationships from decommissioned (old) to approved (new) plant community types are known as ‘lineage transformations’ and are held in the BioNet Vegetation Classification application.
Lineage data can be viewed individually for each plant community type or exported in bulk in spreadsheet format.
Lineage data are comprised of:
- a ‘transformation details’ lineage statement that provides a short summary of the relationship between a decommissioned plant community type (or parent PCT) and the new approved plant community type (or offspring PCT)
- a separate row for each approved plant community type to which the decommissioned type is related
- the date the lineage information was entered into BioNet.
Lineage relationships are determined in different ways depending on the plant community types involved.
Wherever possible, classified floristic survey plots are used. The plot membership of decommissioned plant community types is compared to those which have been revised, providing traceable and quantifiable lineage relationships. Quantitative classification is based on and defined by floristic survey plots that are publicly available in BioNet, so future revisions will use transparent traceable data to determine lineage relationships.
Changes to other plant community type attributes
Other plant community type attributes are also subject to change. Such changes are carefully managed and controlled, but are not covered by the version number system described above. This includes changes to vegetation formation and/or vegetation class, threatened biodiversity association data or vegetation condition benchmarks.
Changes to other attributes are generally considered during coordinated update cycles, but requests to review these can be made at any time to BioNet.