The flora of Australia

The flora is very interesting and unique. Of the 12 thousand. Species of higher plants more than 9 thousand. Endemics, ie. E. Found only on the Australian continent. Among the many species of endemic species of eucalyptus and acacia trees, the most common plant families in Australia. At the same time there are also such plants which are inherent in South America (eg, southern beech). South Africa (members of the family Proteaceae) and the islands of the Malay Archipelago (Ficus, Pandanus, etc.). This indicates that many millions of years ago between the continents existed land ground connection. Since the climate of much of the territory of Australia differs sharply aridity, its flora dominated by xerophytic plants: special cereals, eucalyptus, acacia umbrella, succulent trees (bottle tree and others.). Trees belonging to these communities have a strong root system, which is 10-20, and sometimes up to 30 m into the ground, so that they, as a pump, sucking moisture from great depths. Narrow and dry leaves of these trees are painted mostly in the dull gray-green color. Some of these leaf edge facing the sun, which helps to reduce evaporation of water from the surface. In the far north and northwest of the country, where it is hot and warm north-west monsoon brings moisture, grow tropical rainforests. Their wood composition is dominated by giant eucalyptus trees, fig trees, palms, pandanus leaves with long, narrow, and others. Thick foliage forms a nearly continuous cover, shade the ground. Places on the coast there are thickets of bamboo. In those places where the banks are flat and muddy, develops mangrove vegetation. Rainforests in the form of narrow galleries extend a relatively short distance into the mainland through the valleys pek. The farther to the south, the climate becomes drier and a strong sense of the hot breath of the desert. Forest cover gradually thins. Eucalyptus and acacia umbrella in groups. This area is humid savannah stretching in the latitudinal direction south zone of tropical forests. Of a type of savanna with sparse groups of trees like a park. Shrubby undergrowth about them. Sunlight penetrates freely through the sieve of small leaves of trees and falls to the ground, covered with tall thick grass. For central desert parts of the continent, where it is very hot and dry, characterized by thick, almost impenetrable thickets of thorny shrubs stunted, consisting mainly of eucalyptus and acacia. In Australia, these thickets called Shrubland. Shrubland places interspersed with extensive devoid of vegetation, sandy, rocky or clay desert areas, and places with thickets of high Soddy cereals (spinifex). Eastern and south-eastern slopes of the Great Dividing Range, where much rain falls, covered with dense tropical and subtropical evergreen forests. Most of these forests, as elsewhere in Australia, eucalyptus. Eucalyptus valuable industrially. These trees have no equals in height among the rocks with hard wood; some species reach a height of 150 m and 10 m in diameter. Growth of wood in the forests of eucalyptus big, and so they are very productive. Many in the woods and tree ferns and horsetails, reaching 10-20 m in height. On top of its tree ferns are the crown of large (up to 2 m in length) pinnate leaves. Its bright and fresh herbs, they are somewhat enliven pale bluish-green landscape eucalyptus forests. Higher in the mountains visible admixture of pines and beeches-damarra. Shrub and grass cover in these forests are diverse and dense. In the less humid variants of these forests form a second tier of herbal trees. Tasmania besides eucalyptus many evergreen beeches, related South American species. Ha southwest mainland forests cover the western slopes of the ridge Darling, facing the sea. These forests are composed almost entirely of eucalyptus, reaching a considerable height. The number of endemic species are especially great. Besides eucalyptus widespread bottle trees. They have the original bottle-trunk, thick at the base and tapering sharply upward. In the rainy season in the trunk of trees accumulate large amounts of moisture, which are consumed in the dry season. The undergrowth of the forest a lot of shrubs and grasses, Pestryaev bright colors. In general, the forest resources of Australia are low. The total forest area, including special plantings, consisting mainly of species of softwood (mainly radiata pine), at the end of the 70s was only 5.6% of the country. The first colonists found on the mainland plant species characteristic of Europe. Later in Australia were imported European and other kinds of trees, shrubs and grasses. It is well grafted vine, cotton. Cereals wheat, barley, oats, rice, maize and others. As well as vegetables, many fruit trees and so on.. In Australia in a regular sequence represented all types of soils typical of tropical, subtropical and subequatorial natural zones.

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