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: Big data confirms climate extremes are here to stay

add to favorites email to friend print save as pdf

Related Stories

Evidence of a local hot bubble carved by a supernova

14 minutes ago

I spent this past weekend backpacking in Rocky Mountain National Park, where although the snow-swept peaks and the dangerously close wildlife were staggering, the night sky stood in triumph. Without a fire, ...

Nature inspires a greener way to make colorful plastics

14 minutes ago

Long before humans figured out how to create colors, nature had already perfected the process—think stunning, bright butterfly wings of many different hues, for example. Now scientists are tapping into ...

F1000Research brings static research figures to life

1 hour ago

F1000Research today published new research from Bjorn Brembs, professor of neurogenetics at the Institute of Zoology, Universitaet Regensburg, in Germany, with a proof-of-concept figure allowing readers and reviewers to run ...

Wave energy impact on harbour operations investigated

1 hour ago

Infragravity period oscillations—waves that occur between 25 and 300 seconds with a wavelength between 100m and 10km—can have an impact on berthing operations, depending on a harbour's geometry.

Recommended for you

How might climate change affect our food supply?

3 hours ago

It's no easy question to answer, but prudence demands that we try. Thus, Microsoft and the United States Department of Agriculture (USDA) have teamed up to tackle "food resilience," one of several themes ...

Groundwater is safe in potential N.Y. fracking area

3 hours ago

Two Cornell hydrologists have completed a thorough groundwater examination of drinking water in a potential hydraulic fracturing area in New York's Southern Tier. They determined that drinking water in potable ...

Underwater elephants

19 hours ago

In the high-tech world of science, researchers sometimes need to get back to basics. UC Santa Barbara's Douglas McCauley did just that to study the impacts of the bumphead parrotfish (Bolbometopon muricatum) on cor ...

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.