Threatened species and communities fact sheet
Department of the Environment and Heritage, 2004
About the fact sheet
Plants form the basis of our environment. They release oxygen into the atmosphere and use sunlight, carbon dioxide and minerals to produce food. People and the rest of the living world depend upon this oxygen and food to survive. Plants also provide shelter and breeding sites for animals, and they protect the soil from wind and water erosion. For humans, plants are the source of many valuable products such as building materials, paper and clothing.
In over 200 years of European occupation there have been significant changes to the way native vegetation is managed. Clearing for agriculture and urban development, altered fire and grazing patterns, changed drought and flood patterns, and the introduction of weeds, feral animals and diseases have affected the survival of many plant species.
More than 60 Australian plant species are now thought to be extinct, and over 1180 are threatened. The depletion and degradation of native vegetation communities threatens the long-term health of Australian landscapes. Increasing fragmentation makes it harder for plants to reproduce and makes populations more susceptible to disturbance. Changes to drought and flood patterns have threatened the survival of many plant species.
Fire is a natural event in the Australian environment. However, changes to the frequency and intensity of fires, and to the seasons in which they occur, affect the abundance of plants and the composition of plant communities.
Hard-hoofed animals, such as cattle, horses and sheep, trample native vegetation and compact the soil, which prevents seedling growth and encourages soil erosion. Many native plants cannot survive intense grazing by these introduced animals.
Invasive species have had devastating effects on our native plants. Weeds compete with native plants for space and resources, or stop them recovering after clearing, fire or other disturbances. Many pest animals, such as feral pigs and goats, cause soil erosion and trample native vegetation. Phytophthora, a deadly fungus, also threatens the survival of many Australian plant species. Fertilisers, pesticides and pollution of our rivers and lakes further threaten our ecosystems.