The Tasmanian Wilderness World Heritage Area (TWWHA) is located within the Australasian biotic realm, one of the world's eight realms (Udvardy 1975). Both Australia and New Zealand are well known for their rich and distinctive flora, a feature resulting in part from their isolation from other continental landmasses.
Tasmania is one of Australia's hotspots of botanical diversity and endemism at the large regional scale. Throughout recent geological history, Tasmania has been an occasional island off southeastern Australia and lies at the latitude 42o south, directly in the path of the roaring forties. Tasmania's southerly position, variable topography and soil fertility have given rise to its highly diverse and significant vegetation. There is a strong gradient in precipitation and soil fertility from the southwest to the northeast of Tasmania. In the west, soils are poor and rainfall reaches in excess of 4000 mm per annum. In the east rainfall may be less than 400 mm per annum and the soils are often more fertile.
The flora values of the TWWHA are described for each of the region's main ecosystems since many of the nationally and internationally important themes fit relatively well within these headings. Six broad ecosystem groups are recognised: rainforest; sclerophyll communities (forest, woodland and scrub); alpine and subalpine treeless vegetation; buttongrass moorland; coastal communities; and wetland communities. All of these floristic associations have unique features and values of both national and international significance, which highlight the unusual and outstanding nature of the TWWHA vegetation. Separate sections on the biogeographical origins of the TWWHA flora and its floristic diversity have been added because these topics cross ecosystem boundaries and are issues of such underlying importance to the World Heritage Area listing criteria.
Floristic Values of the Tasmanian Wilderness World Heritage Area (1.12 MB)