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Lake Assal ((アラビア語:بحيرة عسل) , literally 'honey lake') is a crater lake in central-western Djibouti. It is located at the western end of Gulf of Tadjoura in the Tadjoura Region, touching Dikhil Region, at the top of the Great Rift Valley, some west of Djibouti city. Lake Assal is a saline lake which lies below sea level in the Afar Triangle, making it the lowest point on land in Africa and the second-lowest land depression on Earth after the Dead Sea. No outflow occurs from the lake, and due to high evaporation, the salinity level of its waters is 10 times that of the sea, making it the most saline in the world after Don Juan Pond. Lake Assal is the world's largest salt reserve, which is exploited under four concessions awarded in 2002 at the southeast end of the lake; the major share of production (nearly 80%) is held by Société d’Exploitation du Lac and Société d’Exploitation du Salt Investment S.A de Djibouti.〔 The lake, considered a "national treasure", is a protected zone under the law No. 45/AN/04/5L of the National Environmental Action Plan, 2000. However, the law does not define the boundary limits of the lake. Since the exploitation of the salt from the lake was uncontrolled, the Plan has emphasized the need for managing the exploitation to avoid negative impact on the lake environment. The Government of Djibouti has initiated a proposal with UNESCO to declare the Lake Assal zone and the Ardoukoba volcano as a World Heritage Site.〔 ==Geography== Lake Assal is located in the middle of Djibouti, in a closed depression at the northern end of the Great Rift Valley. Situated in the Danakil Desert, it is bounded by hills on the western region. The lake lies at an altitude of below sea level, making it the lowest point of Africa.〔 The lake is characterized by two parts. The dry part of the lake, resulting from evaporation of the lake waters, is a white plain dry lake bed on the west/northwest side, which is a large expanse of salt. The second part is the highly saline water body.〔〔 The watershed area of the lake is .〔〔 Lake Assal, in an oval shape (length and width ),〔 consists of two distinct parts; one is "crystallised salt surface" zone of and the other is the high saline brine area of . The crystallised salt zone extends to a depth of more than whose estimated resource is about 300 million tonnes.〔 The lake measures and has an area of liquid brine . The maximum depth is , whereas the mean depth is , which makes for a water volume of Salt extraction by the Afar nomad tribes of camel drivers and Issas from Lake Assal's salt bank established the ancient caravan routes. These linked the lake with the mountains of Ethiopia for barter trading such items as sorghum, coal, and other commodities. Salt was also bartered with South Abyssinia for items like coffee, ivory, musk, and also (historically) slaves. It was a source of wealth for the local tribes.〔 In the recent two decades, industrial mining has been revived with development of roads linking with the Ghoubbet El Kharab bay by the Gulf of Tadjoura.〔 The present road to Lake Assal is paved.〔〔 The lake is 120 km from Djibouti city. It is also reported that the lake water level is receding as discerned from a 50-ft mark on the banks of the lake from the present water level.〔 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「Lake Assal (Djibouti)」の詳細全文を読む スポンサード リンク
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