Australia's Global Terrestrial Habitats
Habitats are large areas of land or water that contain a geographically distinct assemblage of natural communities that:
- share a large majority of their species and ecological dynamics
- share similar environmental conditions
- interact ecologically in ways that are critical for their long-term persistence.
There are 14 terrestrial habitats or ecozones, found across the globe.
Eight terrestrial habitats are represented in Australia and are shown on the following map:
Australia's 8 terrestrial habitats
Source: Department of Environment, Water, Heritage and the Arts (adapted from WWF)
The main characteristics of the eight habitats found Australia are as described in the following table:
| Terrestrial Habitat | Description and ecoregions |
|---|---|
| Generally found in large, discontinuous patches centred on the equatorial belt and between the Tropics of Cancer and Capricorn, Tropical and Subtropical Moist Forests are characterized by low
variability in annual temperature and high levels of rainfall (>200 centimetre annually). Forest composition is dominated by semi-evergreen and evergreen deciduous tree species. Australia has a small and scattered area of tropical rainforest in Qld, composed of what is believed to be residual fragments of the forests that once covered most of Australia and Antarctica, approximately 15 million years ago. These forests are of particular interest for their southern location and the high degree of endemism of their plant (many with ancient lineages) and animal species. There is also Subtropical Moist Forests on Lord Howe Island and Norfolk Island recognised as there own world ecoregions. They both feature high levels of plant and bird endemism. |
|
Forests in the temperate world experience a wide range of variability in temperature and precipitation. In regions where rainfall is broadly distributed throughout the year, deciduous trees mix with species of evergreens. Species such as Eucalyptus spp and Acacia spp typify the composition of the Temperate Broadleaf and Mixed Forests in Australia. The Eastern Australia Temperate Forests enjoy a moderate climate and high rainfall that give rise to unique Eucalyptus forests and open woodlands stretching from SE Queensland to South Australia. The temperate rain forests of Tasmania are extraordinarily complex and contain relict species from the time when the island was part of the super-continent Gondwana. This biome in Australia has served as a refuge for numerous plant and animal species when drier conditions prevailed over most of the continent. That has resulted in a remarkably diverse spectrum of organisms with high levels of regional and local endemism. |
|
Large expanses of land in the tropics do not receive enough rainfall to support extensive tree cover. The Tropical and Subtropical Grasslands, Savannas, and Shrublands are characterized by rainfall levels between 90-150 centimetres per year. While much of Australia is covered by grassland, savannah ecosystems are far more restricted - being limited to moister areas along the coast with the Kimberley, Top End, and Cape York savannas, along the northern coast, and providing the best examples of this habitat type on the continent. Patches of dry rainforest with high species diversity also occur throughout the ecoregion. |
|
| Temperate Grasslands, Savannas, and Shrublands differ largely from tropical grasslands in the cooler and wider annual temperature regime as well as the types of species found here. Generally speaking, these regions are devoid of trees, except for riparian or gallery forests associated with streams and rivers. Positioned between temperate forests and the arid interior of Australia, the Southeast Australian Temperate Savannas span a broad north-south swatch across QLD, NSW and Victoria. Unfortunately, most of this ecoregion has been converted to sheep rearing and wheat cropping. The original eucalypt vegetation remains only in small fragments. | |
| This major habitat type includes high elevation (montane and alpine) grasslands and shrublands, including the puna and paramo in South America, sub-alpine heath in New Guinea and East Africa, steppes of the Tibetan plateaus, as well as other similar subalpine habitats around the world. In Australia montane grassland and shrublands are restricted to the montane regions of south-eastern Australia above 1300 metres. This region occupies less than 3 % of the Australian landmass and straddles the borders of the Australian Capital Territory, Victoria and New South Wales on the Australian mainland, as well as a significant element in Tasmania. | |
Mediterranean Forests, Woodlands, and Scrub ecoregions are characterized by hot and dry summers, while winters tend to be cool and moist. Most precipitation arrives during these months. Only 5 regions in the world experience these conditions: the Mediterranean, south-central and southwestern Australia, the fynbos of southern Africa, the Chilean matorral, and the Mediterranean ecoregions of California. Although the habitat is globally rare, it features an extraordinary biodiversity of uniquely adapted animal and plant species, which can adapt to the stressful conditions of long, hot summers with little rain. Most plants are fire adapted, and dependent on this disturbance for their persistence. All 5 Mediterranean-climate ecoregions are highly distinctive, collectively harbouring well over 10% of the Earth's plant species. The Fynbos and Southwest Australia shrublands have floras that are significantly more diverse than the other Mediterranean ecoregions. More than 5,500 species of plants have adapted to the South-western Australia Forests and Scrub ecoregion, with nearly 70 percent being endemic. Combined with well-drained, generally sandy soils, these conditions give rise to rare plant and animal communities. |
|
Worldwide, Deserts and Xeric Shrublands vary greatly in the amount of annual rainfall they receive; generally, however, evaporation exceeds rainfall in these ecoregions, usually less than 10 inches annually. Temperature variability is also extremely diverse in these remarkable lands. Many deserts, such as the Sahara, are hot year-round but others, such as Asia's Gobi, become quite cold in winter. Temperature extremes are a characteristic of most deserts. Searing daytime heat gives way to cold nights because there is no insulation provided by humidity and cloud cover. Not surprisingly, the diversity of climatic conditions - though quite harsh - supports a rich array of habitats. Many of these habitats are ephemeral in nature - reflecting the paucity and seasonality of available water. The Great Sandy-Tanami deserts are the richest deserts in Australia that exhibit high levels of local endemism including the richest lizard communities in the world. |
|
| The tundra is a treeless polar desert found in the high latitudes in the polar regions such as sub-Antarctic islands - Macquarie, Heard and McDonald. The long, dry winters feature months of total darkness and extremely frigid temperatures. Structurally, the Tundra is a treeless expanse that supports communities of sedges and heaths as well as dwarf shrubs. Vegetation is generally scattered, although it can be patchy reflecting changes in soil and moisture gradients. Most precipitation falls in the form of snow during the winter while soils tend to be acidic and saturated with water where not frozen. |
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