Biodiversity in freshwater systems is impacted as much or more by environmental change than tropical rain forests, according to University of Oklahoma Professor Caryn Vaughn, who serves as director of the Oklahoma Biological Survey. "When we think about species becoming extinct, we don't necessarily think of the common species in freshwater systems, many of which are declining," says Vaughn.

"We need to be concerned about these declines, because these common species provide many goods and services for humans," she states. "Factors underlying these declines include water pollution, habitat destruction and degradation, and environmental changes, such as overexploitation of water and aquatic organisms, all of which are linked to human activities. Freshwater biodiversity is also threatened by climate change which is predicted to alter species ranges and abundance."

Vaughn studies freshwater mussels, or clams, that live in Oklahoma's rivers. North America contains the highest diversity of freshwater mussels in the world with over 300 species, but over 50 percent of these species are declining. Oklahoma contains 55 mussel species, mainly in rivers in the eastern portion of the state.

The roles freshwater mussels fill in ecosystems have not been studied so far, so Vaughn's study is at the forefront of research on freshwater ecosystems. "We have seen that environmental changes are leading to species shifts in freshwater ecosystems, including changes in Oklahoma's mussel fauna," remarks Vaughn. "We need to understand how these changes will influence the services mussels provide in these systems."

Mussels feed by filtering material from the water with their gills, thus mussels act as a biofiltration system in freshwater ecosystems. Losses of these critical species can result in diminished water quality and added expenses for water treatment. Because they are large with hard shells, mussels also provide or improve habitat for many other aquatic organisms.

Multiple approaches are needed to reach Vaughn's research goal of understanding the goods and services provided by mussel communities, how these may be affected by environmental change and how we can better manage our water resources to protect mussels and meet human needs. The study is being done in southeast Oklahoma where there is an abundance of mussel species.

Vaughn believes we have to rethink how we use water in the future because it will impact quality of life for the next 100 years. "Water is our most precious resource," says Vaughn. "Sustainable water quantity and quality is a fundamental need of both wildlife and humans and is a critical component for economic growth." She works with several state agencies and participates on a task force to address water challenges in the state and make recommendations for protecting this resource.

Vaughn recently published an article on the subject in the January 2010 issue of the scientific journal, BioScience. The National Science Foundation provided funding through a grant for this research.

(ScienceDaily*, 26/01/2010)

*Adapted from materials provided by University of Oklahoma.