CSIRO has prepared this dataset in partnership with the Australian Government Department of Climate Change, Energy, the Environment and Water (DCCEEW) for use in biodiversity assessment and national reporting such as State of the Environment, Ecosystem Accounting, Ecological Knowledge System, and annual corporate reporting metrics for the environment and heritage portfolio. This dataset is a product of the ‘Priority improvements to the Habitat Condition Assessment System’ project. The HCAS v3.1 is a series of 90m gridded datasets depicting habitat condition on a scale between 0.0 (ecosystem removed) and 1.0 (ecosystem in reference condition) for continental Australia. The index represents the contribution that a given site (90m grid cell) makes to the effective area of ecosystem integrity remaining within any given spatial reporting unit, expressed as a proportion of the contribution made by a site in reference condition. Ecosystem integrity is defined as the ecosystem’s capacity to maintain its characteristic composition, structure, functioning and self-organisation over time within a natural range of variability. Reference condition is defined as the condition against which past, present and future ecosystem condition is compared to in order to measure relative change over time. Habitat condition (syn. ecosystem condition) is a generalised estimate for use in whole of biodiversity assessment metrics and may not represent the specific habitat quality requirements of all component species. The data provided is a long-term epoch (also known as the ‘base model’) derived from Landsat remote sensing variables averaged over 35 years (1988-2022) – HCAS31_HCB_1988_2022.tif. This long-term epoch provides the overall ‘best’ estimate of habitat condition derived from the HCAS method, as an expression of the long-term pattern of ecosystem dynamics and capacity to recover following disturbance. The data is provided as a cloud optimised GeoTIFF (COGs) to facilitate use in webmap applications, 90 m grid resolution, Geographic Datum of Australia (GDA) 1994 (Australian Albers, EPSG:3577).Further ReadingCommonwealth of Australia (2021) Geoscience Australia Landsat Analysis Ready Data Collection 3. National Computing Infrastructure, Canberra, Australia. DOI: https://dx.doi.org/10.25914/6099413995ed0.Giljohann KM, Munroe S, Botha E, Liu N, Williams KJ, Ferrier S and Joehnk K (2024) Identifying reference and highly modified sites for use in the Habitat Condition Assessment System (HCAS). CSIRO, Canberra, Australia.Harwood TD, Lehmann EA, Giljohann KM, Williams KJ, Liu N, Ferrier S, Ware C, Donohue RJ, Sivanandam P, Malley C and Schmidt RK (2023) 9-arcsecond gridded HCAS 2.3 (2001-2018) base model estimation of habitat condition and general connectivity for terrestrial biodiversity, ecosystem site condition, annual epochs and 18-year trends for continental Australia. Data Collection. CSIRO, Canberra, Australia. DOI: https://doi.org/10.25919/arew-q819.Liu N (2024) Australian Land Fraction and Derived Masks. Data Collection. CSIRO, Canberra, Australia. DOI: https://data.csiro.au/collection/csiro:62826.Liu N and Newnham G (2024) Methods for developing the Australian Land Fraction and Derived Masks. Supplementary metadata for a data collection from the National Ecosystem Accounting Project. CSIRO, Canberra, Australia.Searle R (2023) HCAS Optimised SLGA Products. Terrestrial Ecosystem Research Network, Canberra, Australia. <https://aussoilsdsm.esoil.io/other/hcas-optimised-slga-products>.Williams KJ, Giljohann KM, Richards AE, Harwood TD, Lehmann EA, Liu N, Ferrier S, Murphy HT, Prober SM, Hosack GR, Tetreault-Campbell S and Schmidt RK (2023) Extended methods used in developing the Habitat Condition Assessment System (HCAS) version 2.3, ecosystem condition account-ready data and experimental accounts for two mixed-use landscapes. A technical report from the Regional Ecosystem Accounting Pilot projects. Publication number: EP2023-1426. CSIRO, Canberra, Australia. DOI: https://doi.org/10.25919/r12v-ya32.Williams KJ, Liu N, Valavi R, Levick SR, Giljohann KM, Johnson S, Botha EJ, Munroe SE, Lehmann EA, Collings S, Searle R, Niel TGV, Newnham G, Paget M, Joehnk K, Hosack GR, Harwood TD, Malley C, Gunawardana D, Sivanandam P, Richards A, Tetreault-Campbell S and Ferrier S (2024) Habitat Condition Assessment System (HCAS) version 3.1: A guide to the 90-metre data collection. Publication EP2024-5394. CSIRO, Canberra, Australia. <https://publications.csiro.au/publications/publication/PIcsiro:EP2024-5394>;
