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Aquatic Conservation Assessment FAQs

The Frequently Asked Questions provide information about the Aquatic Conservation Assessments conducted by the Department of Environment, Science and Innovation and the Queensland Wetlands Program using AquaBAMM.

Bowling Green Bay, Photo by DESI

Quick facts

ACA
Aquatic Conservation Assessments are non-social and non-economic assessments which identify conservation values of wetlands at a user-defined scale.

What is AquaBAMM?

The Aquatic Biodiversity Assessment and Mapping Method (AquaBAMM) assesses the conservation values of wetlands.

The method identifies relative wetland values within a specified study area (usually a catchment). The method uses available data, including data resulting from expert opinion, to produce an Aquatic Conservation Assessment (ACA) for the wetlands within the study area. The results provide powerful decision support information that is easily updated and able to be interrogated through a Geographic Information System (GIS) platform.

The method provides a robust and objective way of assessing wetland values using criteria, indicators and measures (CIM) that are founded upon a large body of national and international scientific literature.

What is an Aquatic Conservation Assessment (ACA)?

An ACA is the final output from an application of the AquaBAMM methodology and tool to assess the relative conservation values of wetlands in a study area. The final ACA output has three major components—a report, expert panel report(s) and a Geographic Information System results dataset.

What is the difference between AquaBAMM and ACA?

The acronym AquaBAMM refers to the Aquatic Biodiversity Assessment and Mapping Method, which is the method used for undertaking an assessment. When an AquaBAMM assessment is run, the resulting product is called an Aquatic Conservation Assessment (ACA).

How was AquaBAMM developed?

The Queensland Environmental Protection Agency, now the Queensland Department of Environment, Science and Innovation developed AquaBAMM and applied it in the Burnett River catchment for riverine wetlands. The methodology was developed with the flexibility and scope to be applied to other wetland types i.e. non-riverine wetlands. Since the release of AquaBAMM and the Burnett River riverine ACA results, the method has been refined and applied to riverine, non-riverine (lacustrine and palustrine) and estuarine wetlands for many parts of Queensland. The methodology can also be used for marine environments.

Has AquaBAMM been peer reviewed?

Yes. The methodology has been peer reviewed on a number of occasions including:

  • a formal peer review in June 2006.
  • unsolicited peer review in June 2006.
  • statistics review in April 2007.
  • sensitivity analysis in June 2009.

Where can I access the AquaBAMM methodology?

AquaBAMM methodology

What wetlands mapping is used for AquaBAMM?

The wetland mapping produced by the Queensland Wetlands Program is used as the core dataset for all ACAs. Wetlands are classified according to a range of criteria, including the type of ecological system (riverine, estuarine, etc.), and their degree of water permanency and salinity. The result is consistent wetland mapping at a scale of 1:100,000, with finer detail in some parts of Queensland (mainly coastal regions) where appropriate data exists.

AquaBAMM usually assesses only natural and near natural wetlands. Therefore not every wetland mapped in the QWP wetlands mapping will be automatically included in an AquaBAMM assessment. The report for each ACA lists the range of wetlands included in the assessment.

How does AquaBAMM define wetlands?

The wetland definition used in AquaBAMM is consistent with the wetland definition developed and applied by the Queensland Wetlands Program.

What does AquaBAMM assess (criteria, measures and indicators—CIM)?

The methodology assesses wetland conservation values using criteria, indicators and measures (CIM list). The criteria, each of which may have variable numbers of indicators and measures, include:

  • naturalness (aquatic)
  • naturalness (catchment)
  • diversity and richness
  • threatened species and ecosystems
  • priority species and ecosystems
  • special features
  • connectivity
  • representativeness

A full list of the Criteria, Indicators and Measures can be found in the AquaBAMM methodology.

Does AquaBAMM include social or economic information?

No. ACAs are non-social, non-economic and tenure blind, designed with the sole intent of identifying conservation values of wetlands.

How is an ACA produced?

An ACA is produced through a process of compiling, analysing and evaluating data and knowledge via desktop analysis of existing spatial datasets in addition to data/knowledge gathered through an expert panel process.

An ACA provides an overall conservation value (AquaScore), ranging from very low to very high, for each spatial unit (e.g. wetland), which is based on eight separate criteria. Each criterion value is formed through a mathematical combination of measures and indicators. A filtering table is then used to determine an overall AquaScore for each spatial unit in the chosen study area. Field truthing is then used to verify the results prior to producing the final reports and GIS result datasets for release.

What ACAs have been completed and released to date?

ACAs release dates

What are the ACA results used for?

The results of an ACA contribute to baseline ecological and ecosystem information available to support natural resource management and planning processes, for both government and non-government organisations. An ACA can have application in:

  • determining priorities for protection, regulation or rehabilitation of aquatic ecosystems
  • on-ground investment in aquatic ecosystems
  • local and regional planning processes
  • impact assessment of development proposals (e.g. dams)
  • water resource management and planning processes
  • identification of significant aquatic assets (e.g. areas mapped as Matters of State Environmental Significance).

How do ACAs relate to other aquatic assessments?

Given the broad definition of wetlands and the variety of assessment needs it is not surprising that many aquatic ecosystem/wetland assessment methods have been developed for use in Australia. ACAs utilise data from existing aquatic ecosystem assessments (e.g. the Directory of Important Wetlands in Australia, Ramsar wetlands, World Heritage areas, fish habitat areas and protected areas), but the ACA results can also be used as an input to other assessments.

ACAs provide a whole of landscape assessment for all wetlands in an area (entire basins/catchments). Other assessments often only represent subsets of what would be evaluated in an ACA. Where an assessment predates an ACA, the results may be incorporated into relevant measures e.g. a Ramsar site identified as significant habitat for migratory species or an estuary noted as important fish habitat/refugia.

What is the difference between an ACA and a Biodiversity Planning Assessment (BPA)?

The terrestrial Biodiversity Assessment and Mapping Methodology (BAMM) is a decision support tool that utilises existing information and expert consensus resulting in a BPA for a bioregion. BAMM is based on the regional ecosystem (vegetation) mapping in Queensland. AquaBAMM was created to specifically deal with wetlands as they are not comprehensively considered within BAMM.

In general, BAMM and AquaBAMM are similar methodologies based on similar criteria. When assessing the full range of biodiversity values across the landscape results from both the BPAs and ACAs are complementary and both should be considered.

Who do I contact for more information, assistance or to provide feedback?

For further details about AquaBAMM or the ACAs can be obtained by emailing biodiversity.planning♲des.qld.gov.au or visit the AquaBAMM webpage.

What criteria does AquaBAMM assess?

The criteria, each of which may have variable numbers of indicators and measures include:

  • Naturalness aquatic—This attribute reflects the extent to which a wetland's naturalness is influenced through factors directly associated with the wetland including presence of exotic flora and fauna, presence of aquatic communities, degree of habitat modification and degree of hydrological modification.
  • Naturalness catchment—The naturalness of the area surrounding a wetland can have an influence on many of the wetland values including: natural ecological processes e.g. nutrient cycling, riparian vegetation, water chemistry, and flow. The indicators assessed in this criterion include: presence of exotic flora and/or fauna, degree of riparian disturbance, degree of overall catchment disturbance which is determined by land use, degree of flow modification via farm storage.
  • Diversity and richness—This criterion is common to many conservation assessments and includes both physical and biological features through indicators as species richness, riparian ecosystem richness and geomorphological diversity.
  • Threatened species and ecosystems—This criterion evaluates threatened species and ecosystems associated with a wetland. Species values are determined by state and federal legislation and include Endangered, Vulnerable or Near Threatened species. Ecosystem values are determined by the Regional Ecosystem status i.e. Endangered and Of Concern.
  • Priority species and ecosystems—Priority flora, fauna and ecosystems are identified the expert panels. Characteristics of aquatic, semi-aquatic and riparian priority species include important food source, critical habitat, disjunct population serious population decline etc.
  • Special features—Special features are areas identified by flora, fauna and ecology expert panels. These features exhibit characteristics beyond those identified in other criteria and which the expert panels consider to be of the highest ecological importance. Special feature values include geomorphic features, unique ecological processes, presence of unique or distinct habitat and presence of unique or special hydrological regimes e.g. spring-fed streams.
  • Connectivity—This criterion is based on the concept that appropriately connected aquatic ecosystems are healthy and resilient, with maximum potential biodiversity and delivery of ecosystem services. Indicators of connectivity include segments of riverine systems that contribute to the maintenance of upstream or downstream significant values, wetlands which retain critical ecological and hydrological connectivity with other wetlands etc.
  • Representativeness—Wetland rarity is determined by the extent to which wetlands are protected by legislation (including National Parks Act, Fisheries Act, Coastal Management Act, or Marine Parks Act etc.). Wetland uniqueness evaluates the relative abundance and size of a wetland or wetland management group within the catchment and sub-catchment. Some indicators within this criterion are based on the underlying wetland typology which currently does not exist in a consistent way for riverine, estuarine or marine wetlands.

A full list of the criteria, indicators and measures can be found in the AquaBAMM methodology

Does ACA data include information on water quality?

Yes. ACAs incorporate water quality data in some measures, especially those relating to wetland condition, but the information is not accessible in a way which makes it useful for assessing downstream water quality impacts.

Can ACAs be updated?

Yes. ACAs can be updated based on a range of factors including the release of new data and they have already been updated for several areas of Queensland.

Are springs included in ACAs?

Springs can be included in non-riverine ACAs by buffering spring points by 100m and including them with the lacustrine and palustrine wetlands.

Are experts used in the assessment process?

Yes. Flora, fauna and ecology expert panels are conducted as part of an ACA. Panels consist of experts familiar with the relevant study area. The panels are identify special features (such as presence of distinct, unique or special geomorphic features), priority species and validate flora and fauna records.

What is the accuracy and scale of the ACA results?

Accuracy: ACAs use the best available data. Peer reviews and formal assessments have shown AquaBAMM attributes to be accurate more than 98% of the time.

The accuracy of the attributes of the ACA is dependent on the underlying base mapping, predominantly the Queensland Wetlands Mapping (QWM). The user should refer to relevant metadata associated with the QWM data for a full description of attribute accuracies. Spatial units with low AquaScore dependability lack data for some of the ACA measures. The dependability score can be used to identify data gaps and also identify ACA results which might alter if more data was available.

Scale: The spatial units for non-riverine wetlands include wetlands mapped in the QWM which are over 1ha in size or 35m wide for linear features, as well as spring wetlands which are mapped with 100m accuracy. The spatial units for riverine ACAs are typically subsections based on digital elevation models or from existing data sets such as the State of the Rivers subsections.

What does the ACA dependability attribute mean?

ACA dependability refers to the proportion of measures used for the assessment for which data was actually available. Dependability is calculated as:

e.g. if 120 measures are selected for the entire assessment and data is available in a particular subsection for only 60 measures, then dependability = 50% for that subsection and the wetlands contained within it.

Data availability is the largest limitation in assessments of this kind. Some spatial units will be data poor or even lack data for some or many of the measures. In these cases a ‘no data’ entry will appear in the results and, for each entry of this type, the dependability of the final AquaScore is reduced.

Critically, an indication of AquaScore dependability enables discrimination between spatial units that actually have lower conservation value and those where a low value has been influenced by data availability. Dependability values can also quickly indicate gaps in the data and potentially provide focus for further work. Dependability is calculated at the AquaScore and criteria level.

What is the AquaScore?

For each spatial unit, a single summary score is derived by combining all of the final criterion scores. This summary score is called AquaScore. The AquaScore for a wetland is determined by a filter table decision number. The filtering table is the process utilised in AquaBAMM to arrive at an overall AquaScore (i.e. very low, low, medium, high or very high) for each spatial unit or wetland. It is based on unique combinations of the individual AquaBAMM criteria ratings. The table provides an ordered series of decisions that are tested against the final combination of criteria ratings for each of the spatial units. Each decision number and consequent AquaScore represents a unique combination of criteria ratings. The filtering table performs a similar function to a weighting process where the individual criteria are weighted based on their individual or combined contribution to the overall AquaScore. This filtering table technique has previously been successfully applied in the BAMM.

How are the ACA results validated?

The verification of the ACA results is supported by a desktop comparison using recent satellite imagery and aerial photography and field verification. Field verification involves visiting a representative set of wetland sites (ranging from very low to very high AquaScore values), to determine if the results accurately reflect what appears on the ground. Accessibility can make this exercise difficult but every effort is made to visit as many wetlands as possible throughout the study area. The number of wetlands visited during field verification varies from assessment to assessment.

How do I interpret riverine ACA results?

Results for riverine ACA’s are provided in two formats, one attributed to the subsection spatial units and the other to the buffered streams within the subsections. Subsections are intended to be contiguous areas in which all surface water flows to a single outlet point (within the limits of available mapping resources and time). The mapped buffered streams within each subsection may not capture all natural streams that exist in the subsection.

How should the ACA results be used?

The single number identifying the conservation value of wetlands (AquaScore) can be used for some purposes but it is recommended that the underlying criteria, indicators and measures (CIM) are also considered in any decision making. For example, a different combination of CIM might help answer a specific question e.g. a user might be interested in identifying wetlands with threatened species and with poor aquatic naturalness scores in order to identify potential rehabilitation sites.

Information on expert panel decisions is also provided in the data, with further information on expert panel special features provided in the ACA reports.

How can the ACA GIS results be accessed?

View the get mapping help page

Where can I find the metadata for the ACA mapping?

View metadata for riverine and non-riverine

How do I find out what each field in the ACA data means?

The metadata provided as part of the ACA release includes definitions of each field in the GIS data. Metadata can be found in the documents folder of each ACA release package.

How do I interpret the GIS attributes?

The ACA GIS data includes all the attributes from the output of the AquaBAMM tool, as well as other supporting information including the identifier codes for the base layers (spatial units, subsections, sub-catchments, study areas and bounding areas), the release date and version number. The ACA results contain information on the calculations and results for criteria, indicators and measures, as well as AquaScore and dependability.

AquaBAMM database results in the ACA GIS data:

To identify the raw data (DA) value for a measure, the field name will be in the format C1I1M1DA which represents the data for criteria 1, indicator 1, measure 1. The thresholded score (TS) for this measure (where 4 indicates the highest conservation value for this measure) would be in the format C1I1M1TS. The field name for the indicator score would be in the format C1I1S which represents the score for criteria 1, indicator 1. The field name for the score for a criterion would be of the format C1R which represents the result for criteria 1. This criteria result score is a categorised score based on the adjusted score for the criteria, e.g. C1ADJ. The AquaScore for a spatial unit can be obtained from the AS_SCORE field. The AquaScore dependability can be obtained from the AS_DEP field, as can the criteria dependability scores from the individual fields C1_DEP, etc.

Information on expert panel defined special features can also be obtained from the ACA GIS results. The EP_DEC_NO field contains the decision number allocated to any expert panel decision, and the SPEC_FEAT field has the name of any expert panel defined special feature attributed to a spatial unit. The expert panel reports for each ACA list each decision number and detailed descriptions of the values identified by the experts.

Queensland Wetland Mapping attributes in the ACA GIS data:

For the non-riverine ACA data many attributes are derived from the QWM. However, non-riverine spatial units may be an aggregation of adjacent QWM wetland ecotope polygons, therefore a spatial unit may contain more QWM values than the ones reported. The rules for whether adjacent wetland ecotope polygons are aggregated follow the rules used in the QWM to derive wetland polygons which may be found in the QWM metadata. Some attributes derived from the QWM do not require aggregation as only features with the same value will be merged e.g. the FIRST_HYDR attribute will represent the hydromodifier attribute (HYDROMOD in QWM) of all wetlands that make up the spatial unit. For other attributes the values will need to be summarised in some way. For example, the field FIRST_WETR is derived from the WETRE attribute in the QWM and provides the regional ecosystem codes that are mapped within one of the wetland ecotope polygons that make up a spatial unit.

What formats are the ACA results available in?

The ACA results are created using a Microsoft Access database. The results table is exported to DBF and linked to the relevant wetlands source GIS layer. A new GIS layer is created and saved as an ESRI shapefile. A number of layer files and an MXD file are also created for use with ESRI ArcGIS. Predefined layer files have been prepared to display the AquaScore results, separate Criteria results and the dependability of the results.

How can I view the ACA results if I’m not using ArcGIS?

If you are not using an ESRI GIS program, you should access the inbuilt or online help file for your program to determine how to import and use ESRI files. Some programs, such as MapInfo, can use shape files directly. For others, such as AutoCAD, you may need to use a utility to import the file. There are also a number of free programs available on the internet (e.g. ArcExplorer which is available from ESRI) that will allow you to perform simple operations such as viewing, navigating and querying shape files. The ACA data packages each come with an ArcGIS map published in ArcReader as a .pmf file.

What spatial units are used in an AquaBAMM assessment?

In implementing an ACA, spatial units need to be defined in order to assign conservation values when they are calculated. The number of spatial units included in any ACA can vary greatly between study areas.

For riverine ACAs, spatial units consist of subsections. Subsections are intended to be contiguous areas in which all surface water flows to a single outlet point (within the limits of available mapping resources and time). Subcatchments are a collection of subsections. Study areas are a collection of subcatchments. The study areas are usually based on the NRM sub-basins data. This hierarchy provides subunits of the study area at small, medium and large scales. Riverine ACA results are released with the spatial units represented by the mapped buffered streams within each subsection, but all natural streams, even those not mapped in the results, are to be taken as covered by the relevant subsection. Subsections are generally of a size that balances reporting needs with data availability and can be determined in a number of ways including modelling (e.g. SedNet, RiverTools) or from existing datasets (e.g. State of the Rivers subsections, Geofabric).

For non-riverine ACAs, spatial units are usually equivalent to palustrine and lacustrine wetlands in the Queensland Wetlands Mapping (QWM) (for which over 80% of the polygon is mapped as a wetland). Individual mapped wetlands are employed as the ACA spatial units. One non-riverine spatial unit represents one Wetland_ID from the QWM, which will consist of one more ecotope/habitat polygons from the QWM dissolved on contiguous area, HYDROMOD and CATCHMENT. Springs and 51–80 RE wetlands (between 51 and 80% of the polygon is mapped as a wetland on the regional ecosystem mapping) are also used in the ACAs and their spatial units effectively represent a single polygon dissolved based on the same rules (contiguous area, HYDROMOD and CATCHMENT) which may contain one or more polygons from the QWM 51–80 RE polygons or the QWM springs layers. QWM spring points are buffered by 100m to create the ACA spring spatial units.

Estuarine ACA spatial units may consist of coastal subsections or QWM polygons dissolved to represent unique estuarine QWM Wetland_IDs.

Marine ACA spatial units have not been generated for an ACA yet and therefore their basis is yet to be determined.

What are the major data sources used in an assessment?

The metadata included with the ACA release packages include a list of all major data sets used for the generation of spatial units and supporting spatial data layers such as subsections, subcatchments, study areas and bounding areas. See the metadata and summary report associated with each ACA for a full list of datasets used in the assessment.


Last updated: 6 December 2022

This page should be cited as:

Department of Environment, Science and Innovation, Queensland (2022) Aquatic Conservation Assessment FAQs, WetlandInfo website, accessed 18 March 2024. Available at: https://wetlandinfo.des.qld.gov.au/wetlands/assessment/assessment-methods/aca/faq/

Queensland Government
WetlandInfo   —   Department of Environment, Science and Innovation