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The Calabar River in Cross River State, Nigeria flows from the north past the city of Calabar, joining the larger Cross River about to the south. The river at Calabar forms a natural harbor deep enough for vessels with a draft of . The Calabar River was once a major source of slaves brought down from the interior to be shipped west in the Atlantic slave trade. Slaving was suppressed by 1860, but the port of Calabar remained important for export of palm oil and other products, until it was eclipsed by Port Harcourt in the 1920s. With improved roads into the interior, Calabar has regained importance as a port and is growing rapidly. The tropical rain forest in the Calabar River basin is rapidly being destroyed, and pollution is decreasing fish and shrimp catches in the estuary. Those that are caught have unsafe levels of contaminants. ==Location== The Calabar River drains part of the Oban Hills in the Cross River National Park. The geology of the river basin includes the Pre-Cambrian Oban Massif, Cretaceous sediments of the Calabar flank and the recent Niger Delta sedimentary basin. The basin is about wide and long, with an area of At one time it was entirely covered by tropical rainforest. The region has a rainy season from April until October, during which 80% of the annual rain falls, with peaks in June and September. Annual rainfall averages . Average temperatures range from in August to in February. Relative humidity is high, between 80% and 100%. The basin has 223 streams with a total length of . This is a small number given the size of the basin. Drainage is poor, so the basin is subject to flooding, gully erosion and landslides. A 2010 study said that flooding had increased in recent years. In 1862 the Zoological Society of London received a description of a new crocodile named ''Crocodilus frontatus'' that had been taken from the Old Calabar River, with a much broader head than in ''Crocodilus vulgaris''. A new bat called ''Sphyrocephalus labrosus'' was also reported. The river system formed by the Cross River, Calabar, Great Kwa and other tributaries forms extensive flood plains and wetlands that empty into the Cross River estuary. The system has an estimated area of As of 2000 about 8,000 tonnes of fish and 20,000 tonnes of shrimp were being caught annually. Shrimp provide a relatively cheap form of protein to the people of Calabar. The fishermen land their catches at Alepan's beach on the Calabar River, and the catch is sold in the surrounding markets. 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「Calabar River」の詳細全文を読む スポンサード リンク
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