Around 25 million years ago, a fissure opened in the Eurasian continent and gave birth Lake Baikal, the deepest lake in the world. The lake is located near the Russian city of Irkutsk, one of the largest cities in Siberia with about half a million population. Like many of Earth’s waterways today, Lake Baikal may be in trouble. That’s the conclusion of a strongly worded Siberian Times article published on May 25, 2016. The article spoke of a recent ecological assessment of Lake Baikal, and gave dire warnings this lake could suffer the same fate as the Aral Sea, formerly one of the four largest lakes in the world, now less than 10% of its original size after the rivers that fed it were diverted by Soviet irrigation projects.
Lake Baikal is currently a natural reservoir – a UNESCO world heritage site – containing around 20% of the world’s unfrozen freshwater. But, according to Siberian Times:
Construction of three hydro power stations on the Selenga River and its tributaries can cause the unique lake to dry out.
The 25 million year old lake is on the edge of environmental catastrophe and if certain measures are not taken, it might disappear just like the Aral Sea.
In total, some 330 rivers and streams flow into Lake Baikal, some large like the Selenga and many small, while its main outflow is the Angara River.
What would be lost if Lake Baikal were to go the way of the Aral Sea? Holding 20% of all unfrozen surface fresh water on Earth, Lake Baikal is unlike other deep lakes in that it contains dissolved oxygen right down to the lake floor. That means creatures thrive at all depths in the lake.
Most of Lake Baikal’s 2,000-plus species of plants and animals are found nowhere else in the world. Scientists believe up to 40 per cent of the lake’s species haven’t been described yet. Species endemic to Lake Baikal have evolved over tens of thousands, perhaps millions, of years. They occupy ecological niches that were undisturbed, until the last few decades.
Lake Baikal’s rich and unique biodiversity includes species like the Baikal seal, also known as “nerpa.” It’s the only mammal indigenous to Lake Baikal.
Scientists aren’t sure how these seals originally got into Lake Baikal. There are two primary hypotheses concerning this question, which you can read about here.
Another famous species native to Lake Baikal is the “omul,” a type of whitefish. It’s part of the Salmon family. This fish is the main product found at local fisheries. Due to overfishing, it was listed as an endangered species in 2004.
In additional to threat from dam-building, industrial development, paper mills, mining, agriculture, and general population growth on the lake’s shores have added toxic compounds, fertilizers and other pollutants into Lake Baikal. For example, a paper mill located on the shore of Lake Baikal used to discharge tons of toxic waste into the lake. The mill was shut down, re-opened, and shut down once again. There was much opposition to opening the mill due to environmental reasons. On the other hand, the mill provided over a thousand jobs and accounted for 80% of the income in a nearby town. Last we heard, authorities are trying to turn the mill into an environmentally-friendly business.Read more: How is pollution changing Lake Baikal?
Bottom line: Russia’s Lake Baikal – located in southern Siberia – is the world’s deepest lake. It is an estimated 5,370 feet (1,632-1,642 meters) deep at its deepest. It provides a home for over 2,000 endemic species such as the omul and the Baikal seal.
Deborah Byrd created the EarthSky radio series in 1991 and EarthSky.org in 1994. Today, she serves as Editor-in-Chief of this website. She has won a galaxy of awards from the broadcasting and science communities, including having an asteroid named 3505 Byrd in her honor. A science communicator and educator since 1976, Byrd believes in science as a force for good in the world and a vital tool for the 21st century. "Being an EarthSky editor is like hosting a big global party for cool nature-lovers," she says.