New study examines density stratification on microorganisms in aquatic ecosystems

March 6, 2012

Microorganisms play pivotal functions in nature, particularly within aquatic ecosystems. Whether in an ocean or a lake, they are key players in the food chain and the vitality of individual ecosystems.

A team of researchers led by Arezoo M. Ardekani, the Rev. John Cardinal O'Hara, C.S.C., Assistant Professor of Aerospace and Mechanical Engineering at the University of Notre Dame, has shown that density stratification, a frequent feature of , has important ecological consequences on these small organisms.

The team recently published a paper in the Proceedings of the National Academy of Sciences that demonstrates that density variations encountered by organisms at pycnoclines have a major effect on the flow field, energy expenditure and nutrient uptake of small organisms. Organisms at pycnoclines, regions of sharp vertical variation in fluid density, afford a competitive advantage due to smaller risk of predation. These results can be used to explain why an accumulation of organisms and particles, which leads to a wide range of environmental and oceanographic processes, is associated with pycnoclines .

Ardekani joined the University in 2011. Her research interests focus on the fundamental properties of multiphase flows of Newtonian and non-Newtonian fluids relevant to biofluids, and micro/nanofluids for use in biomimetic applications, , , and .

Most recently, she was awarded a 2012 National Science Foundation Faculty Early Career Development Award for her work in fluid dynamics of bacterial aggregation and formation of biofilm streamers. Prior to joining the University, Ardekani served as a Shapiro Postdoctoral Fellow at the Massachusetts Institute of Technology and is currently a member of the American Association for the Advancement of Science, American Chemical Society, American Physical Society, American Society of Mechanical Engineers and Society of Rheology.

Explore further: Mixing genomics and geography yields insights into life and environment

Related Stories

Headwater stream nutrient enrichment disrupts food web

December 17, 2009

Human activity is increasing the supply of nutrients, such as nitrogen and phosphorus, to stream systems all over the world. The conventional wisdom -- bolstered by earlier research -- has held that these additional nutrients ...

Diatoms reveal freshwater pollution

May 4, 2010

Researchers in India have demonstrated that microscopic aquatic creatures could be used as the ecological equivalent of a canary in a coalmine for assessing inland freshwater lakes and ponds. Writing in the World Review of ...

Recommended for you

Study suggests fish can experience 'emotional fever'

November 25, 2015

(—A small team of researchers from the U.K. and Spain has found via lab study that at least one type of fish is capable of experiencing 'emotional fever,' which suggests it may qualify as a sentient being. In their ...


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.