Q. Which of the following has/have shrunk immensely/dried up in the recent past due to human activities? - Aral Sea
- Black Sea
- Lake Baikal
Select the correct answer using the code given below: (UPSC Prelims 2018)
Answer:
1 only
Notes: The correct answer is
[A] 1 only. This question focuses on one of the most significant environmental disasters of the 20th and 21st centuries.
- Aral Sea (Statement 1 – Correct): Once the fourth-largest lake in the world, the Aral Sea has shrunk by about 90% of its original size since the 1960s. This was primarily due to a massive Soviet-era irrigation project that diverted the flow of its two main feeder rivers, the Amu Darya and Syr Darya, to grow cotton in the desert regions of Uzbekistan and Kazakhstan.
- Black Sea (Statement 2 – Incorrect): While the Black Sea faces significant environmental issues such as pollution, overfishing, and invasive species, it has not shrunk or dried up. It remains a massive body of water connected to the Mediterranean via the Bosphorus Strait.
- Lake Baikal (Statement 3 – Incorrect): Located in Russia, Lake Baikal is the world's deepest and oldest freshwater lake. While it faces threats from industrial pollution and fluctuating water levels due to hydroelectric dams, it has not "shrunk immensely" in the manner of the Aral Sea. Its volume remains relatively stable compared to the catastrophic desiccation seen in Central Asia.
The drying of the Aral Sea has led to the "Aralkum Desert," where windblown salt and toxic pesticides from the dry seabed cause severe health problems for local populations and have destroyed the regional fishing industry.