Climate Change Alters Base of Tahoe Food Web

Sep 29, 2008
Climate Change Alters Base of Tahoe Food Web

(PhysOrg.com) -- UC Davis researchers at Lake Tahoe this week published the first evidence that climate change alters the makeup of tiny plant communities called algae, which are the very foundation of the web of life in freshwater lakes.

Other scientists had predicted that climate change would reduce the overall amount, or biovolume, of an important algae group called diatoms. However, the UC Davis researchers found that the warming of the lake changed not the overall biovolume but rather the relative populations of various diatom species.

"There are greater numbers of small-sized diatom species in recent years than there were 20 years ago," said postdoctoral researcher Monika Winder, the study's lead author.

"Changing climate conditions, such as warmer air temperatures, have changed the mixing patterns of the lake," explained study co-author Geoffrey Schladow, director of the UC Davis Tahoe Environmental Research Center. "With less mixing, it is difficult for larger algae to stay suspended at the surface of the lake, where there is light to facilitate their growth. This allowed the smaller diatoms, which sink more slowly, to proliferate."

Diatoms form the base of the food chain in large bodies of water, both freshwater and saltwater, around the world. The hugely abundant, single-celled plants are eaten by tiny animals (zooplankton), which are eaten by small fish, which are eaten by bigger fish and birds, and so on to the highest predators in the system.

"It is inconceivable that you could alter the base of the food web and not have other things start changing," Winder said. "What those changes will be, we don't know yet."

Some zooplankton species may decline, which would lead to declines in fish numbers. Clarity may also be reduced because smaller algae stay at the surface longer, scattering light and making the water appear greener.

Schladow noted that this particular finding was possible because of the uncommonly long and detailed record of physical and biological measurements made by UC Davis at Lake Tahoe for the past 50 years.

The new study, titled "Lake warming favours small-sized planktonic diatom species," was published online on Sept. 24 by the journal Proceedings of the Royal Society B. The research was funded by UC Davis and the agencies that have supported the Lake Tahoe Interagency Monitoring Program (LTIMP).

Also a co-author of the study: John Reuter, associate director of the UC Davis Tahoe Environmental Research Center.

Provided by UC Davis

Explore further: Obama says 'no greater threat to planet than climate change'

Related Stories

Quantum dot TVs are unveiled at China tech expo

4 hours ago

At this month's China Information Technology Expo (CITE) event, a headline-maker was the launch of quantum dot televisions, by QD Vision and Konka, the consumer electronics company. QD Vision's calling card ...

A call to US educators: Learn from Canada

7 hours ago

As states and the federal government in the U.S. continue to clash on the best ways to improve American education, Canada's Province of Ontario manages successful education reform initiatives that are equal parts cooperation ...

Recommended for you

Climate censorship gains steam in red states

Apr 17, 2015

While plenty of people found humor in the recent news that officials in Florida and Wisconsin are censoring state workers' ability to talk about, much less work on, climate change, other states are not necessarily laughing. ...

Engineers purify sea and wastewater in 2.5 minutes

Apr 17, 2015

A group of Mexican engineers from the Jhostoblak Corporate created technology to recover and purify seawater or wastewater from households, hotels, hospitals, commercial and industrial facilities, regardless ...

User comments : 2

Adjust slider to filter visible comments by rank

Display comments: newest first

Modernmystic
2.5 / 5 (8) Sep 30, 2008
LOL it may REDUCE fish populations because the base of the food chain has increased. These are the kids in school who picked their noses incessantly and couldn't color inside the lines until the fifth grade....

They just can't admit that something positive could come from climate change. It's like a holy proclamation of their religion...

Thou shalt not admit a warmer Earth could be good in ANY way.

deepsand
2.3 / 5 (6) Oct 01, 2008
LOL it may REDUCE fish populations because the base of the food chain has increased.

WTF?
These are the kids in school who picked their noses incessantly and couldn't color inside the lines until the fifth grade....

So, you know these people personally?
They just can't admit that something positive could come from climate change. It's like a holy proclamation of their religion...

Non sequitur
Thou shalt not admit a warmer Earth could be good in ANY way.

Thou shalt not speak specious BS.

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.