Kellogg Biological Station
Algae research heats up in Litchman lab
Introduction
Long Term Ecological Restoration (LTER) site
Climate adaptation in plants
Cows introduced to pasture grazing, robotic milking
Flipping the carbon switch in ponds
These stories are also available in the June '09 edition of Green Ink
There’s a lot of climate change research happening at KBS, so you might mistake the clear plastic tubes filled with water and stored in a small room just down the hall from Elena Litchman’s lab for ice cores that some absentminded professor allowed to melt.
The contents of these tubes aren’t cross-sections of glaciers, but of lakes – or, more accurately, simulations of lakes. Litchman, a KBS-affiliated professor of zoology who specializes in aquatic ecology, is interested in how shallow and deeper waters mix in lakes, and she uses the tubes to see how different environmental conditions, like nutrient concentrations and light levels, affect that mixing.
Mixing brings oxygen and nutrients to different depths, so it helps determine a lake’s water quality, what types of fish can live in it and – most interesting to Litchman – the kinds and concentrations of algae it supports. Poorly mixed lakes promote the growth of toxic algae, she said. “When there’s no mixing, they’re the king, basically.”
Harmful algae blooms are common, Litchman said, but increases in average temperature and in nutrients from farm runoff have made them more common in recent years. And as the region’s average temperature rises, the blooms are expected to become even more frequent.
In addition to the laboratory simulations, Litchman spends a lot of time sampling actual lakes around KBS. “It’s a really nice place to do aquatic research,” she said, “because there are so many different lakes.” She then analyzes the samples in her lab to determine how well-mixed or nutrient-rich a lake’s water is, and how those factors relate to algae blooms.
By sampling year after year, Litchman is also able to see a correlation between the blooms and weather data. “We can really mechanistically explain this connection between the temperature and the occurrence of the blooms, which is really cool,” she said.
Litchman and her colleagues are also monitoring the spread of an invasive type of toxic cyanobacteria, or blue-green algae, that’s native to tropic and subtropical regions but is increasingly common in Michigan.
“It produces toxins, and it fixes nitrogen, so it can have a big impact on ecosystems, on lakes and rivers. And what is interesting is that it’s spreading northwards because of changing climate,” she said.
