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Moorland or moor is a type of habitat found in upland areas in temperate grasslands, savannas, and shrublands and montane grasslands and shrublands biomes, characterised by low-growing vegetation on acidic soils. Moorland nowadays generally means uncultivated hill land (such as Dartmoor in South West England), but the Old English ''mōr'' also refers to low-lying wetlands (such as Sedgemoor, also SW England). It is closely related to heath although experts disagree on precisely what distinguishes the types of vegetation. Generally, moor refers to highland, high rainfall zones, whereas heath refers to lowland zones which are more likely to be the result of human activity.〔 〕 Moorland habitats are most extensive in the neotropics and tropical Africa but also occur in northern and western Europe, Northern Australia, North America, Central Asia, and the Indian subcontinent. Most of the world's moorlands are very diverse ecosystems. In the extensive moorlands of the tropics biodiversity can be extremely high. Moorland also bears a relationship to tundra (where the subsoil is permafrost or permanently frozen soil),〔 appearing as the tundra retreats and inhabiting the area between the permafrost and the natural tree zone. The boundary between tundra and moorland constantly shifts with climate change. == Heather moorland == Heathland and moorland are the most extensive areas of semi-natural vegetation in the British Isles. The eastern British moorlands are similar to heaths but are differentiated by having a covering of peat. On western moors the peat layer may be several metres thick. Scottish ‘muirs’ are generally heather moors, but will also have extensive covering of grass, cotton-grass, mosses, bracken and under-shrubs such as crowberry, with the wetter moorland having sphagnum moss merging into bog-land.〔 There is uncertainty about how many moors were created by human activity. Rackham writes that pollen analysis shows that some moorland, such as in the islands and extreme north of Scotland, are clearly natural, never having had trees,〔Birks and Madsen (1979). ''Journal of Ecology'', 67.〕 whereas much of the Pennine moorland area was forested in Mesolithic times.〔Turner and Hodgson (1979). ''Journal of Ecology'', 67.〕 How much the destruction of this forest was caused by climatic changes and how much by human activity is uncertain.〔 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「moorland」の詳細全文を読む スポンサード リンク
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