A new guide has been published by the Environmental Protection Authority and the Department of Parks and Wildlife on Flora and Vegetation Surveys for Environmental Impact Assessment. The document is essential reading for consultants undertaking surveys for EIA as well as organisations that commission them. Its release provides further clarity on the practice of flora and vegetation surveys, from planning through to collection and reporting.
It is especially important to note that some of the information in this new guide varies from pre-existing EPA documents or is altogether new. Some key points are highlighted below.
The lead botanist should have a minimum of five years’ experience in the survey region and be leading for the entire duration of the survey
Broad guidance on the timing of primary surveys (optimal timing) is provided by botanical provinces:
- Northern – Wet season (January to March)
- Eremaean – 6 to 8 weeks after the wet season (March to June)
- South-west and South-western Interzone – Spring (September to November)
Consideration of the need for flexibility to accommodate interannual variations in the timing of seasons as well as extremes such as drought and flood is also noted.
Number of quadrats in Level 2 surveys
A minimum of three quadrats per vegetation unit is to be surveyed. This contrasts with Guidance Statement No. 51 (Environmental Protection Authority 2004) where the minimum was two. The necessity for a larger number of quadrats is also emphasised for when a vegetation unit is large, heterogeneous or dispersed across multiple areas.
The guide also notes that quadrats should be supplemented with other survey methods in order to obtain a comprehensive species list for an area. These methods include: opportunistic collections, systematic transects and targeted inspections.
Analysis of the floristic composition of quadrat data using cluster techniques is the preferred method for classification in Level 2 surveys; as opposed to classification from description of structure and dominant species. Complementary analyses that include or exclude subsets of the data (e.g. annuals) are encouraged where they may aid interpretation. The importance of good survey design is also highlighted for achieving satisfactory outcomes from a statistical approach to classification.
Astron maintains a stable and highly experienced botanical team that is well equipped to complete surveys to the standard expected under this new Technical Guide. Senior Botanists have a decade or more experience in surveys across the Pilbara, southwest and other regions. The team is renowned for high quality data collection and reporting. They are also supported by dedicated programmers, statisticians and mapping specialists who ensure that best practice approaches to sampling design, and data management, analysis and presentation, are implemented.
For information on flora and vegetation surveys, please contact our Biodiversity Manager, Dr Stuart Pearse (08 9421 9600) or submit an online form and we'll get in touch with you. Download and read the Technical Guide – Flora and Vegetation Surveys for Environmental Impact Assessment.
Environmental Protection Authority 2004, Terrestrial Flora and Vegetation Surveys for Environmental Impact Assessment in Western Australia, Guidance Statement 51, Environmental Protection Authority, Perth.