Plant Species
Spinifex - A sharp-pointed tussock grass that grows in the form of hummocks, thrives on sand dunes and rocky slopes. Long roots grows in a way that allows each stem get eat its own water and nutrient supply. Burning spinifex produces a strong black smoke, used a smoke signals to communicate with families and groups a long distance away. Aboriginal tribes also burned the grass to collect the resin from the burning material to use as a glue for adhering handles on stone axes. Soft spinifex grows up to 6 inches in height, thriving in arid, infertile soil in the Australian desert.
Desert Bloodwood - Grows on the plains of the Great Sandy Desert. This tree grows up to 30 feet in height and features rough bark, tough and leathery bark, and sap that looks like thick red blood. The roots store water for use in dry periods. In April through October, the tree produces yellow and white flowers with nectar that provides food for several desert animals including possums and insects
Paperbark - The paperbark tree gets its name from its layered and papery bark. It typically grows to about 75 feet in height although it can also grow as a smaller shrub in some areas. The tree’s new shoots, covered in thick silky hairs, give the tree a somewhat silvery appearance. Stands of paperbark occur in swampy, coastal areas in humid, hot regions. From March to December, the tree produces flowers that grow up to 5 inches in length. Once the flowers fade, small fruits appear with seeds ready for collection in October or November. The oil from the three makes a good insect repellent.
Bramble Wattle - A thorny tree growing up to 25 feet in height and features bluish-green leaves with fragrant pale yellow balls of flowers that bloom in the spring. Papery pods containing seeds the size of lentils appear after the flowers fade. The tree provides dense shade and thrives in sunny areas and grows best in medium to heavy soils or in sandy soils where it rains more frequently and relies on underground water to thrive.
Desert Walnut - Certainly one of the most conspicuous trees in the desert, with it's deep green foliage and gnarled bark. Grows up to 14 metres in height, this tree varies in size depending on its habitat. It prefers stony flatlands and seasonally moist spinifex grasslands. Aboriginal people of the Kimberely region are known to use the leaves, bark and fruit of the Desert Walnut and make a medical infusion out of it. This strong infusion is applied to cuts, sores and rheumatism.
Invasive Species
Parkinsonia, or Parkinsonia Aculeata may be a spiny shrub or a small tree. It grows 2 to 8m high, with a maximum of 10 meters. P. aculeata was introduced to Australia as an ornamental tree and for shade in around 1900. It is now a serious weed widespread through Western Australia, the Northern Territory, and Queensland, covering around 8,000 square kilometers of land. It forms in dense thickets, preventing access for humans, native animals and livestock to waterways. The fruits (seedpods) float, and the plant spreads by dropping pods into the water, or the pods are washed downstream by seasonal flooding.
Weed management costs the Australian economy $4 billion yearly. Weeds are considered the second greatest threat to biodiversity after land clearing. Almost half of Australia's 220 declared weeds were introduced deliberately, one-third of these as garden ornamentals, such as Parkinsonia.
Weed management costs the Australian economy $4 billion yearly. Weeds are considered the second greatest threat to biodiversity after land clearing. Almost half of Australia's 220 declared weeds were introduced deliberately, one-third of these as garden ornamentals, such as Parkinsonia.
Adaptations
Desert plants tend to look very different from plants native to other regions. They are often swollen, spiny, and have tiny leaves that are rarely bright green. Their strange appearance is a result of their adaptations to the desert climate. Aridity is sole trait that defines a desert and is what desert organisms must adapt to. Plants must be able to absorb large quantities of water in short periods, because desert rains are often light and brief, and the soil dries rapidly under intense sun.
The Desert Bloodwood Tree has tough leathery leaves and has the ability to store water in their roots while the Spinifex thrives on the poorest, most arid soils in Australia. It is thanks to Spinifex that the Australian Deserts haven’t become Sahara-like with bare-shifting sand. Spinifex is also tough and indigestible to most animals except termites and has roots that go down a long way: approximately 3 metres. Generally the roots develop from the same nodes as the shoots so that each shoot has its own personal water supply. The spiky leaves contain a lot of silica which makes them stiff and rigid.
The Desert Bloodwood Tree has tough leathery leaves and has the ability to store water in their roots while the Spinifex thrives on the poorest, most arid soils in Australia. It is thanks to Spinifex that the Australian Deserts haven’t become Sahara-like with bare-shifting sand. Spinifex is also tough and indigestible to most animals except termites and has roots that go down a long way: approximately 3 metres. Generally the roots develop from the same nodes as the shoots so that each shoot has its own personal water supply. The spiky leaves contain a lot of silica which makes them stiff and rigid.
Pyramid of Energy |
Symbiosis |
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In the desert, animals must work together, use another, or take advantage of others to ensure their survival. This is the process of symbiosis.
There are three types of Symbiosis: Parasitism, Commensalism, and Mutualism, In Mutualism, both organisms benefit from each other. In commensalism, one organism benefits while the other organism is unaffected. In parasitism, one orgamism benefits while one is harmed. An example of mutualism is the Desert bee and Cactus. In some deserts, bees depend on cacti since they act as a major food source for them. In return the cacti depends on bees to pollinate them so they can reproduce. An example of commensalism is the creosote bush growing under the shade of a tree, or an Australian holly shrub. An example of parasitism are fleas living on the body of coyotes and other desert animals. This type of parasitism is biotrophic, because the host organism is harmed, but doesn't die. The other type of parasitism is necrotrophic, where the host organism is harmed to an extent that it dies. An example of this is the interaction between the praying mantis and wasp, where the lasp lays its eggs in the praying mantis' eggs. When the wasp's eggs hatch its larvae feed on the eggs of praying mantis and make their way out. |
Species at Risk
There are currently no specific endangered plant species in the Great Sandy Desert. However, fire management, feral animals, and overgrazing pose threats to this ecoregion. Some of the most invasive animals species include the Feral pig and Feral cat.
Section by Nick Tang