Climate change threatens Lake Baikal's unique biota

May 01, 2009

Siberia's Lake Baikal, the world's largest and most biologically diverse lake, faces the prospect of severe ecological disruption as a result of climate change, according to an analysis by a joint US-Russian team in the May issue of BioScience.

The lake is considered a treasure trove for biologists and was designated a World Heritage Site by UNESCO because a high proportion of its rich fauna and flora are found nowhere else. Perhaps the most alarming imminent threat stems from the dependence of the lake's on large, endemic diatoms, which are uniquely vulnerable to expected reductions in the length of time the lake is frozen each winter.

The article was written by Marianne V. Moore, of Wellesley College in Massachusetts, and five coauthors, including four from Irkutsk State University in Russia. Moore and colleagues note that Lake Baikal's climate has become measurably milder over recent decades, and that annual precipitation is expected to increase. The average ice depth in the lake is known to have decreased in recent decades, and the ice-free season to have increased. Changes in the lake's food-web composition have been documented.

Future shortening in the duration of ice cover is expected to curtail the growth of the lake's endemic diatoms, because unlike most diatoms, they bloom under the ice in springtime and are highly dependent on ice cover for their reproduction and growth. The diatoms constitute the principal food of tiny crustaceans abundant in the lake, and these are in turn preyed upon by the lake's fish. Moreover, the crustaceans could be affected by changes in the transparency of the ice, an expected result of shifting precipitation patterns and changes in wind dynamics.

Shortened periods of and changes in the ice's transparency may also harm the Baikal seal, the lake's top predator and the world's only exclusively freshwater seal. Because the seals mate and give birth on the ice, premature melting of the ice forces them into the water before molting and drastically reduces their fertility.

A warmer, wetter climate may be the principal threat to Lake Baikal's unique biological heritage, but it is not the only one. The secondary effects of climate change, including greater nutrient inputs and industrial pollution from melting permafrost, may also exact a toll on an already-stressed ecosystem.

The authors stress that Russians have long been dedicated to the well-being of Lake Baikal, and that there is substantial support for its protection. Nonetheless, they say, stepped-up monitoring is necessary. Furthermore, international commitments and action will be needed to limit there, which is arguably the most pervasive danger to the lake.

Source: American Institute of Biological Sciences (news : web)

Explore further: Hopes, fears, doubts surround Cuba's oil future

add to favorites email to friend print save as pdf

Related Stories

Water pollution continues at famous Russian lake

Mar 24, 2008

Despite widespread concerns about preserving the world’s largest body of fresh water, researchers report that pollution is continuing in Russia’s fabled Lake Baikal. The study is scheduled for the April ...

Scientists: Less ice on Great Lakes during winter

Mar 23, 2009

(AP) -- Ice cover on the Great Lakes has declined more than 30 percent since the 1970s, leaving the world's largest system of freshwater lakes open to evaporation and lower water levels, according to scientists associated ...

Small Organisms, Great Proxies

Oct 23, 2006

The present and past compositions of communities of single-celled algae in several Canadian lakes and their relationship to the known climate record suggest that these organisms and the lakes they reside in ...

Recommended for you

Hopes, fears, doubts surround Cuba's oil future

8 hours ago

One of the most prolific oil and gas basins on the planet sits just off Cuba's northwest coast, and the thaw in relations with the United States is giving rise to hopes that Cuba can now get in on the action.

New challenges for ocean acidification research

Dec 19, 2014

Over the past decade, ocean acidification has received growing recognition not only in the scientific area. Decision-makers, stakeholders, and the general public are becoming increasingly aware of "the other carbon dioxide ...

Compromises lead to climate change deal

Dec 19, 2014

Earlier this month, delegates from the various states that make up the UN met in Lima, Peru, to agree on a framework for the Climate Change Conference that is scheduled to take place in Paris next year. For ...

User comments : 1

Adjust slider to filter visible comments by rank

Display comments: newest first

GrayMouser
5 / 5 (2) May 01, 2009
Climate change has always affected the biota. Get used to it, the biota has.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.