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Lake Faguibine is a lake in Mali on the southern edge of the Sahara Desert situated 80 km west of Timbuktu and 75 km north of the Niger River to which it is connected by a system of smaller lakes and channels. In years when the height of the annual flood of the river is sufficient, water flows from the river into the lake. Since the Sahel drought of the 1970s and 1980s the lake has been mostly dry. Water has only rarely reached the lake and even when it has done so, the lake has been only partially filled with water. This has caused a partial collapse of the local ecosystem. ==Lake Faguibine system== The lake forms part of a system of five interconnected low-lying depressions that fill to variable depths depending on the extent of the annual flood of the Niger River. Lake Faguibine is by far the largest of these depressions with an area of 590 km2.〔.〕 The low annual rainfall in the area (less than 200 mm) only has a marginal effect on the water levels in the depressions. The depressions are connected to the Niger River by two channels. The more southerly Kondi channel (64 km in length) branches from the Niger a few kilometers downstream of Diré〔.〕 and then meanders across the Killi floodplain. The larger and more northerly Tassakane channel (104 km in length) branches from the Niger further downstream near Korioumé and then meanders across the Kessou floodplain. The two channels unite to form a single channel to the east of Goundam which after another 20 km flows into the southern end of Lake Télé. Lake Télé is connected at its northern end to Lake Takara. Water flows out of the northern end of Lake Takara, across a rocky sill at Kamaïna and then turns west passing the village of Bintagoungou to reach Lake Faguibine. Both Lake Télé and Lake Takara need to be completely filled before the water can flow over the sill at Kamaïna and begin to supply Lake Faguibine. In a similar manner two depressions to the east of Lake Faguibine (Lake Kamango and Lake Gouber) only start to fill once Lake Faguibine is full. To completely fill the 590 km2 of Lake Faguibine requires about 4 km3 of water. This represents around 17 percent of the average discharge of the Niger (1970-1998) at Diré. The lake bed is very fertile and the ideal situation for the sedentary farmers is when the lake is only partially filled. This allows crops to be cultivated around the border of the lake and the growth of ''Echinochloa stagnina'' ("bourgou") in low lying areas to provide dry season pasture. This regime requires much less water – only around 0.5 km3. 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 Faguibine」の詳細全文を読む スポンサード リンク
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