Remnant vegetation in Queensland
Remnant vegetation in Queensland: Analysis of remnant vegetation 1997–1999–2000–2001-2003-2005, including regional ecosystem information
What is remnant vegetation?
Remnant vegetation is defined in the Vegetation Management Act 1999 as vegetation shown on a regional ecosystem or remnant map. 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 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.
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—that is, 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 through the use of grazing, fire or mechanical mowing. In addition, variations in the composition and condition of the non-woody vegetation cannot be readily and consistently recognised from Landsat TM imagery. The EPA therefore has adopted a two-step process of mapping remnant grasslands and other non-woody vegetation types: mapping extent according to time since cultivation, and then making a site assessment based on the composition of the vegetation if required.
What is in the report?
The report provides scientific data and statistics on the extent of Queensland’s remnant vegetation, and regional ecosystems for 83% of the state.
The report is based on detailed survey and mapping. It provides a comprehensive analysis of the amount of pre-clearing and remnant vegetation in Queensland and the extent of clearing of remnant vegetation, based on individual regional ecosystems. This includes data for bioregions, subregions, local government areas, catchments, natural resource management areas and Queensland electoral districts.
Is this report about tree clearing?
The Department of Natural Resources and Water produces a separate report that assesses woody vegetation clearing, that is, the clearing of trees and shrubs. That report is called the State Land and Trees Study (SLATS) and does not record the clearing of non-woody vegetation nor regional ecosystems.
The EPA’s report has a broader focus and study parameters, as it measures the clearing of regional ecosystems, including grasslands, heathlands and mangroves.
Why have a remnant vegetation report?
The report provides information and consolidated maps to support planning and decision-making for Queensland’s legislation, for biodiversity planning, for planning by local government, natural resource management agencies and landholders.
What is the purpose of the data?
This information is essential for regional groups, non-government organisations, government departments, local government and business, for planning and management purposes.
Why is the EPA producing this report?
The Queensland Herbarium, EPA is the lead agency for regional ecosystem survey and mapping for the state.
Summary of key points
- The clearing rate of remnant vegetation and regional ecosystems in the 2003-2005 period was 243,000 hectares per year.
- The average annual clearing rates for remnant vegetation from 1997 to 2005 were:
- 2003–2005 243,000 hectares per year
- 2001–2003 365,000 hectares per year
- 2000–2001 251,000 hectares per year
- 1999–2000 642,000 hectares per year
- 1997–1999 414,000 hectares per year
- In the 2003 to 2005 period remnant regional ecosystem clearing occurred mainly on leasehold tenure (52%) with 46% on freehold tenures.
- The majority of the remnant vegetation clearing between 2003 and 2005 occurred in the Mulga Lands (49%), Brigalow Belt (26%), Desert Uplands (10%) and Mitchell Grass Downs (7%) bioregions.
Further information on the vegetation survey and mapping program and regional ecosystems can be found at http://www.epa.qld.gov.au/REDD
Certified regional ecosystem maps and data can be found at http://www.epa.qld.gov.au/REMAP and http://www.epa.qld.gov.au/REDATA respectively.
Last updated: 27 February 2009
