Print

Remnant regional ecosystem vegetation in Queensland

This report presents state-wide, bioregion and subregion analysis of remnant vegetation extent of regional ecosystems in Queensland for the period 1997-2019 and replaces Accad et al., (2019).

The report provides statistics on the extent of remnant regional ecosystem vegetation for the entire state of Queensland and extends the reporting period to include 2017-2019. The report is based on the detailed regional ecosystem survey and mapping Version 12.0 Regional Ecosystems (2021) and Version 5.0 Bioregions and subregions of Queensland (Figure 1), which are available on the Queensland Globe and Open Data, QSpatial.

The report presents bioregional and subregional analysis of the extent of Queensland’s regional ecosystems pre-clearing and as remnant vegetation from 1997 to 2019. The analysis includes the extent of clearing of remnant vegetation for individual regional ecosystems by tenure and several other themes. The rate of remnant vegetation clearing is also documented as hectares per year.

The report provides essential regional ecosystem extent information and consolidated maps to support state and local government, natural resource management organisations, business and landholders in vegetation management, planning and development.

The extent of remnant vegetation in Queensland has declined by 2.44% (4.2 M ha) between 1997 and 2019 and is now 80.065% (see Table 1).

Table 1. Remnant vegetation extent in Queensland

Year

Remnant (ha)

Percent of Queensland

Pre-clear (ha)

172,855,991

100%

Remnant 1997

142,612,143

82.503%

Remnant 1999

141,727,991

81.992%

Remnant 2000

141,066,058

81.609%

Remnant 2001

140,831,037

81.473%

Remnant 2003

140,087,515

81.043%

Remnant 2005

139,615,918

80.770%

Remnant 2006b

139,238,696

80.552%

Remnant 2009

139,056,647

80.447%

Remnant 2011

139,002,645

80.415%

Remnant 2013

138,920,848

80.368%

Remnant 2015

138,726,224

80.255%

Remnant 2017

138,505,023

80.127%

Remnant 2019

138,397,701

80.065%

Bioregion and subregion analysis of remnant regional ecosystem vegetation 1997-2019

Figure 1. Area analysed for regional ecosystem statistics by bioregion and subregion.

Remnant regional ecosystem vegetation analysis by bioregion and subregion 2017-2019

The average annual rate of clearing of remnant regional ecosystem vegetation in Queensland between 2017 and 2019 was 54,357 hectares per year (Figure 2) and occurred in the:

  • Mulga Lands bioregion (43.2% of clearing in Queensland) largely within West Warrego, Langlo Plains and West Bulloo subregions;
  • Brigalow Belt bioregion (27.9% of clearing in Queensland) largely within Beucazon Hills, Belyando Downs, Southern Downs and Anakie Inlier subregions;
  • Mitchell Grass Downs bioregion (12.5%) largely within Southern Wooded Downs and Central Downs subregions;
  • Desert Uplands bioregion (7.4%) largely within the Jericho, Bogie River Hills and Prairie – Torrens Creeks Alluvials subregions;
  • Southeast Queensland bioregion (2.9%) largely within Moreton Basin and Gympie Block subregions;
  • Cape York Peninsula bioregion (1.7%) largely within Weipa Plateau subregions.
  • Einasleigh Uplands bioregion (1.4%) largely within Broken River and Kidston subregion;
  • Gulf Plains, New England Tableland, Central Queensland Coast, Channel Country, Wet Tropics and Northwest Highlands bioregions each recorded less than 1% of the clearing of remnant vegetation in Queensland (see Figure 3).

In 2017–2019, 54% of remnant regional ecosystem clearing occurred on freehold tenure, with 42% on leasehold tenures, and 6% on other tenures.

Average annual clearing rate of remnant regional ecosystem vegetation 1997-2019

Figure 2. The average annual clearing rates for remnant regional ecosystem vegetation from 1997 to 2019. The clearing rate of remnant regional ecosystem vegetation in the 2017-2019 period was 54,357 hectares per year
Figure 3. Average annual clearing rate of remnant regional ecosystem vegetation as a percentage of the starting year by subregion
Figure 4. Remnant regional ecosystem vegetation in 2019 as a percentage of the pre-clearing extent by subregion

Bioregion and subregion analysis of remnant regional ecosystem vegetation shows that the New England Tableland bioregion has the lowest extent of remnant vegetation of Queensland’s 13 bioregions (36.16%). The Brigalow Belt bioregion has the second lowest remnant extent (41.22%) and includes the Tara Downs and Taroom Downs subregions which have the lowest subregional remnant extent in Queensland, with 5.95% and 6.95% respectively (Figure 4). The remnant regional ecosystem vegetation analysis MS Excel zip file is available from the download section below.

Regional ecosystem analysis

Figure 5. The regional ecosystems with the highest rate of clearing during 2017-2019 is the Brigalow Belt bioregion regional ecosystem 11.12.1
Figure 6. The regional ecosystems with the second highest rate of clearing during 2017-2019 is the Mulga Lands regional ecosystem 6.5.8

The regional ecosystems with the most remnant vegetation cleared during the years 2017 to 2019 were regional ecosystem 11.12.1, Eucalyptus crebra +/- Corymbia erythrophloia shrubby woodland. E. melanophloia is often present and may be locally dominant. Also includes localised areas dominated by E. persistens. Occurs on ranges on igneous rocks. (Figure 5) with 5,766 ha cleared, and regional ecosystem 6.5.8, Acacia aneura, Eucalyptus populnea +/- Eremophila gilesii subsp. gilesii low woodland (Figure 6) with 4,803 ha cleared. The regional ecosystem analysis MS Excel zip file is available from the download section below.

Broad vegetation group analysis

The clearing of remnant vegetation during 2017-2019 mainly occurred in the following broad vegetation groups (BVG 1:5M):

  • Acacia aneura (mulga) dominated open-forests, woodlands and shrublands (BVG 9) 37,226 ha
  • Eastern eucalypt woodlands to open-forests (BVG 3) 18,137 ha
  • Eucalypt dry woodlands on inland depositional plains (BVG 5) 17,218 ha
  • Other acacia dominated open-forests, woodlands and shrublands (BVG 10) 17,048 ha Mixed species woodlands – open woodlands, includes wooded downs (BVG 11) 6,201 ha
  • Tussock grasslands, forblands (BVG 13) 4,302 ha
  • Eucalypt open forests to woodlands on floodplains (BVG 4) 4,259 ha.

Analysis by other themes

The clearing of remnant vegetation during 2017-2019 (on percent basis) mainly occurred in the following:

  • Catchments: Warrego River (18% of the total remnant clearing in Queensland), Paroo River (10%), Suttor River (8%), Barcoo River (8%), Cloncurry River (6%), Thomson River (7%), Bulloo River (6%) and Belyando River (6%);
  • Natural Resource Management Areas (NRM): Southern Queensland Landscapes (47% of the total remnant clearing in Queensland), NQ Dry Tropics (18%), Desert Channels Group (14%), Northern Gulf Resource Management Group (17%), Fitzroy Basin Association (6%) and Burnett Mary Regional Group (4%);
  • Local Government Areas (LGA): Murweh Shire (14% of the total remnant clearing in Queensland), Quilpie Shire (11%), Barcaldine Regional (8%), Whitsunday Regional (7%), Paroo Shire (7%), Isaac Regional (7%) Bulloo Shire (6%) and Blackall Tambo Regional (6%); and
  • Queensland State Electoral districts: Warrego (45% of the total remnant clearing in Queensland), Gregory (22%), Burdekin (14%) and Traeger (6%).

Maps and statistical data for each of the above are available from the download section below.

Download tables and maps

NB: This report provides analyses of remnant regional ecosystems vegetation for the entire state.

Citation

Information contained on this report and available for download should be cited as:

Accad, A. Kelley, J.A.R., Richter, D., Neldner, V.J., and Li, J. (2021). Remnant Regional Ecosystem Vegetation in Queensland, Analysis 1997-2019. Queensland Department of Environment and Science: Brisbane.

Appendix

Remnant vegetation includes both woody and non-woody vegetation as defined below.

Woody remnant regional ecosystems vegetation

Woody vegetation is mapped as remnant where the dominant canopy has greater than 70% of the height and greater than 50% of the cover relative to the undisturbed height and cover of that stratum and is dominated by species characteristic of the vegetation's undisturbed canopy.

An undisturbed stratum (or layer) is defined as one that shows no evidence of extensive mechanical or chemical disturbance (logging, clearing, poisoning, etc.) evident in field inspections or on the available historical aerial photographic record.

The Methodology for Survey and Mapping of Regional Ecosystems and Vegetation Communities in Queensland provides an assessment sequence for mapping vegetation cover (Figure 7).

Non-woody remnant vegetation

Non-woody vegetation is vegetation in which the ecologically dominant stratum is composed of grasses and /or other non-woody vegetation. Defining remnant status in non-woody dominated vegetation, such as grasslands, on the characteristics of the height and cover of the canopy (i.e. the grasses and forbs) is not practical.

The dominant layer in these vegetation types is highly variable according to seasonal conditions, and can be rapidly modified by grazing, fire or mechanical mowing. Neither can variations in its composition and condition be readily and consistently recognised from Landsat TM imagery. The Queensland Herbarium’s two-step process for mapping remnant grasslands and other non-woody vegetation types is therefore to:

Map the extent as remnant vegetation unless there is evidence from imagery of disturbance e.g. cropping in the last 15 years; or an on-site assessment disqualified it as remnant on the basis of species composition or cover.

Figure 7. Flow chart showing assessment sequence for mapping vegetation cover (source: Methodology for Survey and Mapping of Regional Ecosystems and Vegetation Communities in Queensland Figure 3)

Related information