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Sclerophyll is a type of vegetation that has hard leaves and short internodes (the distance between leaves along the stem). The word comes from the Greek ''sklēros'' (hard) and ''phyllon'' (leaf). Sclerophyllous plants occur in many parts of the world,〔C. Michael Hogan. 2010. (''Leather Oak, Quercus durata''. Encyclopedia of Earth. National Council for Science and Environment ). Washington DC〕 but are most typical in the chaparral biomes. They are prominent throughout western (Perth), eastern (Sydney) and southern (Adelaide) parts of Australia,〔(【引用サイトリンク】title=Sydney Coastal Dry Sclerophyll Forests )〕 in the Mediterranean forests, woodlands, and scrub biomes that cover the Mediterranean Basin, Californian woodlands, Chilean Matorral, and the Cape Province of South Africa. ==Australian bush== Most areas of the Australian continent able to support woody plants are occupied by sclerophyll communities as forests, savannas or heathlands. Common plants include the Proteaceae (Grevilleas, Banksias and Hakeas), tea-trees, Acacias, Boronias, and the Eucalypts. The most common sclerophyll communities in Australia are savannas dominated by grasses with an overstorey of Eucalypts and Acacias. Acacia (particularly mulga) shrublands also cover extensive areas. All the dominant overstorey Acacia species and a majority of the understorey Acacias have a scleromorphic adaptation in which the leaves have been reduced to phyllodes consisting entirely of the petiole.〔Simmons, M. 1982. Acacias of Australia. Thomas Nelson, Melbourne〕 Many plants of the sclerophyllous woodlands and shrublands also produce leaves unpalatable to herbivores by the inclusion of toxic and indigestible compounds which assure survival of these long-lived leaves. This trait is particularly noticeable in the eucalypt and Melaleuca species which possess oil glands within their leaves that produce a pungent volatile oil that makes them unpalatable to most browsers.〔Florence, R. G. 1996. Ecology and silviculture of eucalypt forests. CSIRO Publishing, Collingwood.〕 These traits make the majority of woody plants in these woodlands largely unpalatable to domestic livestock.〔Mott, J. J., and J. C. Tothill. 1984. Tropical and subtropical woodlands. in G. N. Harrington and A. D. Wilson, editors. Management of Australia's Rangelands. CSIRO Publishing, Melbourne〕 It is therefore important from a grazing perspective that these woodlands support a more or less continuous layer of herbaceous ground cover dominated by grasses. Sclerophyll forests cover a much smaller area of the continent, being restricted to relatively high rainfall locations. They have a eucalyptus overstory (10 to 30 metres) with the understory also being hard-leaved. ''Dry sclerophyll'' forests are the most common forest type on the continent, and although it may seem barren dry sclerophyll forest is highly diverse. For example, a study of sclerophyll vegetation in Seal Creek, Victoria, found 138 species. Even less extensive are ''wet sclerophyll'' forests. They have a taller eucalyptus overstory than dry sclerophyll forests, 30 metres or more (typically Mountain Ash, Alpine Ash, Messmate Stringybark or Manna Gum), and a soft-leaved, fairly dense understory (tree ferns are common). They require ample rainfall — at least 1000mm (40 inches). 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「Sclerophyll」の詳細全文を読む スポンサード リンク
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