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The Queensland tropical rain forests are a terrestrial ecoregion located in northeastern Australia and belonging to the Australasian ecozone. The forest contains the world's best living record of the major stages in the evolutionary history of the world’s land plants. The history of the evolution of marsupials and songbirds is also well represented. The ecoregion covers of northeastern coastal Queensland, from the coast up a series of plateaus and tablelands to the mountains behind the coast. The ecoregion comprises three separate sections. The northern area, which includes Cairns, is the largest, from 15°30’ to 19°25’ south latitude. This northern section is also known as the Wet Tropics bioregion. ==Flora== The Queensland tropical rain forests are designated one of the Global 200 ecoregions. The ecoregion is the largest remnant of Australia's rain forest flora, home to ancient assemblage of plants, called the Antarctic flora, presently characteristic of New Zealand and southern Chile. Fossil pollen records indicate closed forest covered most of Australia between 50 to 100 million years ago. These forests represent the closest living remnant of the vegetation type from which all of Australia's unique marsupials developed.〔 The vegetation remained across Australia and Antarctica until about 15 million years ago. Conifers of the southern hemisphere family Araucariaceae are the characteristic tree species. In the northern section of the ecoregion, Kauri commonly form the forest canopy, with ''Agathis robusta'' most common at lower elevations, and ''A. microstachya'' and ''A. atropurpurea'' predominant at higher elevations. In the southern sections, ''Araucaria cunninghamii'' is predominant, with ''Araucaria bidwillii'' dominant in two small areas. Conifers in the family Podocarpaceae are also present, including genera ''Podocarpus'' and ''Sundacarpus''. The forests are thick with vines, ferns, epiphytes, and palms. These forests are limited to areas of high rainfall and good soils. In waterlogged soils, the rainforest flora gives way to ''Melaleuca'' thickets, and on poor soils and in drier areas ''Eucalyptus'' becomes dominant. The rainforest flora is intolerant of fire, and where periods of drought have allowed devastating fires, the rainforest flora has retreated, allowing fire-tolerant ''Eucalyptus'' to become established. If a relatively wet period persists, the rainforest flora may reestablish itself. It is thought that the land management practices of the aboriginal Australians, which involve setting regular fires to keep the eucalyptus woodlands open, may have encouraged the expansion of eucalyptus forests at the expense of the rainforest flora. These rainforests seem to have retreated considerably since the arrival of the aboriginals' ancestors 50,000 years ago, and are presently limited to isolated pockets comprising less than 2% of the continent's area. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Queensland tropical rain forests」の詳細全文を読む スポンサード リンク
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