Q13. Which of the following has/have shrunk immensely/dried up the recent past due to human activities?
Aral Sea
Black Sea
Lake Baikal
Select the correct answer using the code given below: (a) 1 only (b) 2 and 3 only (c) 2 only (d) 1 and 3 only
Answer: A
Aral Sea: The Aral Sea is a saline lake located in Central Asia that was once the world’s fourth largest Salt Lake. In the 1960s the Aral Sea, which was the drainage basin for Kyrgyzstan, Turkmenistan, Tajikistan, Uzbekistan, Pakistan, Afghanistan, and Kazakhstan, began to shrink as the Soviet Union began to divert water for agricultural purposes. The Aral Sea, which was once 26,300 square miles in size had decreased in size by 2007 to only 10% of its original area.
Black Sea: Past 60 years, the oxygen-rich top layer of the Black Sea decreased from 140 meters to 90 meters deep, which amounts to an over 40 percent dip in habitable waters. Two existing causes behind the shrinkage: an abundance of nutrients, particularly algae that led to great consumption of oxygen and global warming. The Black Sea has lost more then a third of its habitable volume. The habitable area in Black Sea is shrinking, but the actual volume is not shrinking immensely.
Lake Baikal: In 2015, Russia officially declared Lake Baikal an emergency zone because of a catastrophic drop in its water level. Baikal is the globe’s largest freshwater lake and is on the UNESCO World Heritage list. Lake Baikal hasn’t shrunk immensely yet. Certainly, its water is shrinking. But, it’s not ‘immense’ like Aral Sea. If one has to go for two options, the intensity of shrinkage should be either equal or comparable. Case of Aral Sea is extreme and Lake Baikal’s present condition, which is better, is no comparison to Aral Sea’s fate
