Chott Melrhir
Chott Melrhir, also known as Chott Melghir or Chott Melhir and Lake Tritonis in ancient myths, is an endorheic chott-kind of salt lake in northeastern Algeria. It is the westernmost part of a series of depressions which extend from the Gulf of Gabès into the Sahara. It was formerly known as Lake Tritonis. They were created between Miocene and Early Pleistocene as a result of compression accompanying the formation of the Atlas Mountains. With the maximum area of about, it is the largest lake in Algeria. It lies almost entirely below sea level and contains the lowest point in Algeria,. Its size varies over the year and is usually larger than from east to west. The nearby cities are Biskra, El Oued and Touggourt.
Hydrology, geology and geography
During the rain season in winter, the lake is filled by numerous wadi, mostly from north and north-west. The largest of them are the Djedi and Arab running from west to east down the slopes of Aurès Mountains. Others include Abiod, Beggour Mitta, Biskra, Bir Az Atrous, Cheria, Demmed, Dermoun, Derradj, Djedeida, Djemorah, Halail, Horchane, Ittel, Mechra, Melh, Mzi, Messad, Oum El Ksob, Soukies, Tadmit and Zeribet. In summer, the lake and most of the rivers feeding it dry out, and Chott Melrhir turns into a salt pan. The annual water evaporation varies between 9.6 and 20 km3, and evaporation from soil nearby the lake can reach 14 km3.Chott Melrhir is separated from the nearby Chott Meorouane, which lies south-west, by a strip of permanently dry land which can be as narrow as 4 kilometers in some places. The bottom of the lake is mostly composed of gypsum and mud and is covered in salt in summer. The lake emits a garlic-like odor. Although the dry soil in and around the lake appears arable, it is nearly barren due to the high concentration of salt. For the same reason, the soil absorbs much condensation overnight that keeps it partly humid during much of the day.