Sunday, April 21, 2019

An ecological paradox: the Dead Sea is dying

The Dead Sea, also called Al-Bahr Al-Mayyit in Arabic, is the lowest point on Earth. The only source of water is the Jordan River, which in turn is an outlet for the freshwater lake known as the "Sea of ​​Galilee".
The upper basin of the Jordan-Galilee system covers Syria, Lebanon, Israel, Jordan and Palestine. Important volumes of water in this basin are used for irrigation (mainly in Israel) and due to the very dry climate, the Dead Sea has a continuous water deficit.
The average salt concentration in the Dead Sea is 33.7% which is almost ten times the salinity of the ocean water (approximately 3.5%)
At the moment its surface and coasts are to 430.5 meters under the level of the sea, that is the lowest elevation of the Earth.
The Dead Sea is divided into two "bodies of water", a larger northern basin about 50 kilometers (31 miles) long and 15 kilometers (9 miles) wide at its widest point and a smaller one in the south connected to the main one through a channel. .
The level of the lake decreases continuously at a rate of 1.5 meters per year, accelerating gradually. It is expected to reach 500 meters below sea level around the year 2050. At the same time, the area of ​​the lake is decreasing. Of more than 1,050 km2 in 1930, it has now been reduced to less than 600 km2.
The political situation does not help. If the countries of the basin do not coordinate efforts and the planning of the Dead Sea will disappear completely by the end of the century.
Despite its name, the Dead Sea is not a "dead" water body.
While it is true that higher organisms (fish, for example) can not survive in Dead Sea water, several microorganisms can. In fact, several bacteria and microscopic algae live in its waters. These microorganisms can survive because they are well adapted to hyper-salinity conditions. On the other hand, during very rainy periods or floods, the influx of fresh water changes the chemical composition of the Dead, thus increasing the volume and quantity of microorganisms that live there. In those periods, the surface of the water becomes a bright red, which indicates the presence of certain seaweed (Dunaliella).
A little known fact is that in certain areas and levels, the Dead Sea actually contains fresh water. This comes from freshwater springs that are in its lower part. Near these springs can be found more types of microorganisms: unicellular algae, cyanobacteria and sulfo-bacteria. Other microorganisms that were found at the bottom of the Dead Sea include almost 80 species of fungi.
Many of the microorganisms found in the Dead Sea are unique creatures, some of which had not previously been known to science.

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