Examining Microbial Biodiversity
Recently our Water Quality Monitoring program teamed up with Dr. Robert Hilderbrand, Associate Professor at the University of Maryland Center for Environmental Science Appalachian Laboratory, to look at another dimension of water health in the Jones Falls stream. Here, Dr. Hilderbrand talks about the microscopic organisms that make the Jones Falls unique.
Our understanding of the microbes inhabiting streams (the stream microbiome) is in its infancy because they have been difficult to measure. Recent technological advances can now examine the DNA in water samples and tell us what is living in the stream. Understanding the patterns and degree of microbial biodiversity may lead to better ways to assess, monitor, and classify streams.
Partnering with University of Maryland
Researchers from the Appalachian Laboratory and Horn Point Laboratory have partnered with Blue Water Baltimore to explore the stream microbiome at 12 monitoring stations across the Jones Falls watershed. Using DNA sequencing of water samples, we found over 900 different, yet identifiable types of microbes in Jones Falls watershed streams.
The microbiomes of Jones Falls watershed streams were generally more similar to other urbanized streams than to those in more forested watersheds, but there were clear and broad differences along the length of the Jones Falls watershed, and some sites looked similar to more forested streams. Interestingly, runoff from a large rain event resulted in the stream microbiomes of nearly every Jones Falls station looking very similar to each other.
This homogenization during the rain runoff was probably a result of microbes carried into streams from the surrounding landscape – yards, sidewalks, parking lots, etc. It is also a very clear demonstration that what we do in the watershed eventually makes its way into our streams.
While we are still trying to figure out what it all of the results mean, we have high expectations. We hope to use our findings to predict stream health at sites where using fish or benthic invertebrates are impractical. We also plan to test the ability of samples collected during storm runoff to be used in monitoring and assessing the terrestrial portions of watersheds.