Many court battles have been fought over regional ecosystem mapping. Andrew, the principal of Forest & Sea consulting was the lead consultant in the first test case under the Vegetation Management Act in the year 2000. More recently, he mapped wetlands associated the controversial proposed Cape Alumina mine near the Wenlock River. These challenging situations have provided reason to develop a comprehensive understanding of vegetation mapping process and a number of useful tools which are discussed below. Some of these tools are available to community groups and students on application (send an e-mail to Andrew@forestsea.com)
The Queensland Government’s vegetation mapping system is an ambitious attempt to map the vegetation across a region that is bigger than most of the world’s countries. Regional ecosystem mapping is simple in concept but it is often very difficult to determine which regional ecosystem (RE) you are standing in, when you are in the field. Some of the issues that Forest & Sea Consulting has encountered include:
- determining which RE is present from a list of extremely similar REs;
- vegetation that does not fit any RE description;
- vegetation which does not fit any of the REs listed for an area; and
- in determining whether vegetation is remnant or non-remnant.
As obtaining a reliable RE description for clients is often essential to being able to plan projects, we developed a tool kit for determining REs. The first thing to realise is that RE descriptions as presented in the Regional Ecosystem Definition Database (REDD) are derived from Corveg data rather than directly from observations made in the field. Features which catch the eye in the field are not always present in RE descriptions and conversely RE descriptions are heavy with features that do not stand out at all such as a ‘very sparse shrub layer’. The Corveg database contains all of the vegetation data collected in the field by Queensland Government botanists. The data it contains is based on measurements collected from a ’secondary vegetation’ transects usually 50 m long in which foliage cover and stem density and strata membership is recorded for each species. Site details such as slope, disturbance and soil are also recorded. Corveg has its roots in land system mapping, which pre-dates regional ecosystem mapping. In fact the Corveg system is indexed on a variety of vegetation mapping codes and is independent of the regional ecosystem framework. Regional ecosystem descriptions are based on a review of the structural and floristic information stored within the Corveg system for a particular vegetation aerial photo pattern. The practical implication of this is that when several similar REs are present, you really have to collect your own data in the Corveg format and then derive a structural and floristic description of the vegetation that is in the RE format, so that you can compare your RE description with the one from the REDD.
Collecting data in the Corveg format sounds like a lot of effort, however it has its rewards. Almost all of the words used in a RE description are defined terms rather than casual observations, for example the words ‘lower slopes’ refer to a landscape element that is defined in the Australian Soil and Land Survey Field Handbook. When it comes to distinguishing very similar REs, it is essential to be able to identify and understand the relevance of these defined terms. Every part of a RE description is derived from Corveg data and there are no wasted words so if anyone wishes to master the regional ecosystems, they should be prepared to invest time and effort into learning all of the species and the precise meanings of all the landscape element terms. Filling in Corveg data sheets ensures that you think about soils and subtle landscape features when you are still in the field.
The Queensland Herbarium has produced a guide on collecting data to Corveg standards which is available from them as a pdf document. The reference for this work is:
Neldner, V.J., Wilson, B. A., Thompson, E.J. and Dillewaard, H.A. (2005) Methodology for Survey and Mapping of Regional Ecosystems and Vegetation Communities in Queensland. Version 3.1. Updated September 2005. Queensland Herbarium, Environmental Protection Agency, Brisbane. 128 pp.
Unfortunately the guide has not been refined to the point where the entire process of documenting vegetation can be learned from it. It is an incomplete textbook and parts of it are written by people who should not be allowed to write textbooks. The gaps and issues only become apparent when you try to validate RE mapping using the Corveg or RE map modification process. The regional ecosystem process is also still evolving and progress is being made toward fixing some of the limitations of the system.
