Brief description
This data collection comprises, for continental Australia, 9-arcsecond gridded HCAS version 2.3 (2001-2018) base model (v2.3) estimation of habitat condition and general connectivity for terrestrial biodiversity, an inferred local pressures subindex using the HCAS v2.3 as an input, ecosystem site condition derived from HCAS v2.3 and the inferred local pressures analysis, 18 annual epochs and trends (2001 to 2018), and a series of ancillary datasets to support their use. HCAS v2.3 builds on and updates HCAS v2.1. The National Connectivity Index method was used to estimate general connectivity using the HCAS v2.3 base model as an input.Minimal enhancements included:
•\trefined reference sites used as representative benchmarks for estimating habitat condition as the proximity to reference (high levels of ecosystem integrity);
•\trevised scaling algorithm used to calibrate habitat condition in the range 0.0 (lowest) to 1.0 (highest);
•\tdevelopment of ecosystem site condition by incorporating the effects of inferred local pressures;
•\ta trend analysis based on 18 annual epochs (2001 to 2018) with consideration given to temporal auto-correlation effects;
•\tevaluation of the results (detailed in the accompanying technical report);
•\ta technical report documenting these changes and enhancements and comparison with HCAS v2.1.
Other aspects of the HCAS v2.1 modelling process remained the same. A product brief provided with this collection summarises the included datasets. Guidance on how to use the data are provided in the accompanying technical report (Extended methods used in developing the Habitat Condition Assessment System (HCAS) version 2.3, ecosystem condition account-ready data and experimental accounts for the Flinders, Norman and Gilbert river catchments in Queensland and the Western Australian Wheatbelt) and ecosystem accounting application examples (see related data collections).
Lineage: The HCAS v2.3 base model applied the same algorithms as the HCAS v2.1 base model except for the benchmarking process which used a random sample of reference sites from an updated version of the national collection of inferred reference sites.
The HCAS v2.3 product suite was developed using a combination of:
a)\ttime series remote sensing metrics, derived from the CSIRO MODIS Collection 6 fractional cover dataset comprising persistent and recurrent green vegetation cover, litter (persistent brown vegetation), and bare ground;
b)\tGridded environmental layers, including climate from the 9s climatology for continental Australia 1976-2005, soil and landscape data from the Soil and Landscape Grid of Australia aggregated to 9s; and
c)\tSpatial inference training data representing reference condition sites (locations in natural areas that are the least modified examples of their type), supplemented by expert knowledge from three pilot ecosystem accounting areas.
The HCAS v2.3 base model updated HCAS v2.1 to address (as far as possible):
•\trefined, inferred reference sites to incorporate new data on the extent of gazetted areas in the National Reserve System, native vegetation extent from national vegetation mapping, and more recent national-level data on land use and infrastructure locations
•\taddition of expert-nominated reference sites from two ecosystem accounting pilots – one in north Queensland and the other in Western Australia Wheatbelt; and removal of reference sites that experts nominated as modified
•\ta revised random-stratified subsample of reference sites to fill gaps in sampling some wetland edges and coastal areas
•\ta revised scaling algorithm for the calibration step in HCAS to derive the score ranging from 0.0 (habitat condition removed) to 1.0 (habitat in reference condition). The simple piecewise linear rescaling algorithm has two inflection points to simulate a non-linear rescaling of the initial uncalibrated index.
•\tdata from the PREDICTS project were back-transformed and related to mapped Australian land uses to enable the area-weighted coordinates for the inflection points to be consistently defined for relatively natural areas (defined by the inferred reference sites) and highly modified areas (defined by ALUM version 8 intensive land uses in 2015-16)
•\tan inferred local pressures index derived from HCAS v2.3 outputs as a proxy for the matrix of land uses in the local neighbourhood surrounding a site of interest that potentially negatively influences the realised condition at that site
•\tthe local pressures model was a distance-weighted average of HCAS habitat condition within a 2 km window around the site of interest, with the influence of distance modelled as an exponential decline
•\tthe original HCAS v2.3 output and the inferred local pressures subindex were recombined using a geometric mean calculation to derive a new product 'ecosystem site condition'
•\tthese analyses were applied to the base model long-term epoch (2001 to 2018) and the 18 annual epochs between 2001 and 2018
•\ta new approach to the trend analysis was developed with consideration given to temporal auto-correlation effects and applied to the annual epochs.
These enhancements only applied to the benchmarking part of the HCAS workflow, as well as the scaling and post-processing of HCAS outputs. All other parameters associated with the input data, the reference vegetation model, and parameters for selecting the reference sites to use as benchmarks for each test site, remained the same. Those details are provided in the HCAS v2.1 technical report “Habitat Condition Assessment System (HCAS version 2.1): Enhanced method for mapping habitat condition and change across Australia”, https://doi.org/10.25919/n3c6-7w60.
This data collection also includes an update to the National Connectivity Index version 2.0 (NCI v2) using the HCAS v2.3 base model as an input.
Available: 2024-05-11
Data time period: 2001-01-01 to 2018-12-31
Subjects
Accounting, Auditing and Accountability |
Commerce, Management, Tourism and Services |
Conservation and Biodiversity |
Engineering |
Environmental Sciences |
Ecological Applications |
Ecosystem condition |
Environmental Assessment and Monitoring |
Environmental Management |
Geomatic Engineering |
HCAS |
Habitat Condition Assessment System |
Landscape Ecology |
MODIS |
NCI |
National Connectivity Index |
Photogrammetry and Remote Sensing |
Sustainability Accounting and Reporting |
bare ground |
biodiversity |
climate |
collection 6 |
ecosystem accounts |
ecosystem integrity |
environmental-economic accounting |
fractional cover |
general connectivity |
habitat condition |
landform |
litter |
persistent vegetation cover |
recurrent vegetation cover |
reference condition |
reference site |
remote sensing |
satellite |
site condition |
soil |
substrate |
surface water |
terrestrial |
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Identifiers
- URL : data.csiro.au/collection/csiro:58717
- Handle : 102.100.100/601560
- DOI : 10.25919/AREW-Q819
