Aral Sea Crisis
Corroded ships lie stranded in salt drenched sand as the rushing of water and life in general has become a mere memory. Once the world’s fourth largest lake, the Aral Sea has been reduced in fifty years to little more than a toxic desert.
The Aral Sea lies in Central Asia, between Southern Kazakhstan and Northern Uzbekistan and was originally fed by the Amu Darya and Syr Darya rivers. In the 1960s, the Soviet government began diverting the rivers to irrigate the surrounding desert region, particularly to produce cotton. Although the sea level has dropped about 23 meters since the onset of the diversion, water loss reached its peak in 2014 when the eastern lobe of the South Aral Sea, the center of the original lake, dried up entirely.
To add to the difficulty, as the sea loses water and becomes more shallow, it takes less incoming solar radiation to heat, increasing evaporation and creating a positive feedback loop. As more water evaporates, the water’s salinity increases. Salinity increased 14 percent in only the first decade after the diversion, exceeding the threshold for many marine animals. From 1960 to 2004, surface salinity rose from ten parts per thousand to 92 parts per thousand. Commercial fishing catches, once 44,000 tons per year, stopped entirely by 1980.
“There were over 60,000 fishing jobs supported,” Professor of Biology & Environmental Studies Emily Saarinen commented. “There used to be major ports in the southern regions of the lake, big villages that supported fishing and tourism, and now it takes about five hours to drive up to even get from these ghost towns up to where the water actually is, and what water is there is pretty salty.”
Vegetation has also been reduced by at least 40 percent as a result of increased salinity. Without ground cover, the surface of the land is left exposed, leading to dust storms and increased desertification, yielding the land unusable. A total of six million hectares of agricultural land have been destroyed as a result of salinization and desertification thus far. Without water to moderate temperatures, local climate changed as well; winters became colder and summers became hotter.
Additionally, soil erosion also leads to an increase in the use of fertilizers as a way of compensation, polluting in not only the remains of the Aral sea, but the air too, as dust storms carry it and spread the ecological damage. Dust storms, often between 150 and 300 kilometers wide, are also more prevalent as a result of the crisis. The drying of the sea leaves behind exposed land and large amounts of salt. When winds circulate they pick up the mixture and distribute it as far as 500 kilometers away from its original source. It has been estimated that about 43 million metric tons of salt have been removed from the seabed between 1960 and 1984. As more seabed becomes exposed, winds blow more contaminated soil into surrounding croplands, which only means more water will be needed to make suitable agricultural land.
“When something like this happens it’s pretty hard to go back,” Saarinen said. “You certainly can not go back in the amount of time that it took to make that devastation, you can not fix it in 50 years.”
Although previously considered low, biodiversity in the region is now a major issue. Of the 24 species of fish, 200 some species of free-living macroinvertebrate and 180 land animal species, none of the fish species survived, less than 30 macroinvertebrate species still live and less than a few dozen land animals remain.
“As you take water out, you are concentrating the salt that remains,” Saarinen said. “So all the organisms that lived in the lake, fish, invertebrates and other things, they aren’t adapted to live in salty conditions, and most of them have died out.” Despite all the damage that may be irreversible, Saarinen holds, and teaches her students, hope for the future.
“With environmental disasters it’s important to think of solutions… on a local scale or governmentally it’s to restore or maintain natural processes, and generally try and consume less, try and reduce your own carbon footprint. Some of it is also understanding our own value of water. Florida is the wettest state in the country, yet we still have desalination plants. We have plenty of water but there’s an illusion that we will always have enough water. So let’s learn from the lesson and use water responsibly and value water for what it really is.”
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