|Site description: Gingin Banksia Woodland TERN SuperSite is located on the Swan Coastal Plain, approximately 10 km southwest of Gingin, near Perth, Western Australia, sited on land traditionally owned by the Yued group of the Noongar people. The site has an elevation of 51 m and 2 km from the University of Western Australia International Gravity Wave Observatory.|
The Gingin Banksia Woodland SuperSite is located in a natural woodland of high species diversity (overstorey dominated by Banksia spp.) that overlays the Gnangara groundwater mound, Perth’s most important groundwater resource. The mean annual precipitation is 641mm for this coastal heath woodland. The overstorey is dominated by Banksia spp. mainly B. menziesii, B. attenuata, and B. grandis with a height of around 7 m and leaf area index of about 0.8. There are occasional stands of eucalypts and acacia that reach to 10 m and have a denser foliage cover.
There are many former wetlands dotted around the woodland, most of which were inundated all winter and some had permanent water 30 years ago. The water table has now fallen below the base of these systems and they are disconnected and are no longer permanently wet. The fine sediments, sometimes diatomaceous, hold water and they have perched water tables each winter. There is a natural progression of species accompanying this process as they gradually become more dominated by more xeric species.
The soils are mainly Podosol sands, with low moisture holding capacity. Field capacity typically about 8 to 10%, and in summer these generally hold less than 2% moisture. The water table is at about 8.5 m below the surface, and a WA Dept of water long-term monitoring piezometer is near the base of the OzFlux tower.