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The Agulhas Bank (, from Portuguese for Cape Agulhas, ''Cabo das Agulhas'', "Cape of Needles") is a broad, shallow part of the southern African continental shelf which extends up to south of Cape Agulhas before falling steeply to the abyssal plain. It is the ocean region where the warm Indian Ocean and the cold Atlantic Ocean meet. This convergence leads to treacherous sailing conditions, accounting for numerous wrecked ships in the area over the years. However the meeting of the oceans here also fuels the nutrient cycle for marine life, making it one of the best fishing grounds in South Africa. ==Extent and characteristics== The Agulhas Bank stretches approximately along the African coast, from off Cape Peninsula (18°E) to Port Alfred (26°E), and up to from it. The bank is deep near the coast and reaches before dropping steeply to on its southern edge.〔 The shelf spans an area of with a mean depth slightly over . The National Spatial Biodiversity Assessment 2004 recognised 34 biozones nested within 9 bioregions (of which four were offshore). The National Biodiversity Assessment 2011 replaced these ecozones and biozones with the terms ecoregions and ecozones. In 2011, the Agulhas Ecoregion was divided into four distinct ecozones: Agulhas inshore, Agulhas inner shelf, Agulhas outer shelf, and Agulhas shelf edge. 33 different benthic habitats types were identified on the Agulhas Bank. There are dozens of warm temperate reefs along the coast of the Agulhas Ecoregion spanning from below sea level. Many rocky sub-tidal reefs are of aeolianite or sandstone origin, but granite, quartzite and siltstone reefs are also present. The Agulhas reefs are very heterogeneous and include several possible different sub-types. Some of the reefs are within protected areas, but only a few of those protected areas include protection from fishing. 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「Agulhas Bank」の詳細全文を読む スポンサード リンク
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