Title:  Effects  of Urbanization on Sediment Microbial Communities in Lotic Ecosystems

A thesis submitted to the faculty of the Graduate School in candidacy for the degree of Master of Science.

by Bradley Drury

Department of Biology
Chicago, Illinois

Friday , January  27, 2012, 1:00 PM, LSB,  Room 312

Abstract

The world is becoming increasingly urbanized, with the majority of the world’s population now living in urban areas. Urbanization has the potential to significantly alter lotic ecosystems and the services they provide. Benthic microbial communities are key components of lotic ecosystems due to their contributions to primary production and nutrient cycling. Two types of human inputs associated with urbanization that may impact benthic microbial communities in lotic ecosystems are the input of wastewater treatment effluent and the input of emerging contaminants, including pharmaceuticals and personal care products.  This work examines the effects of treated WWTP effluent on benthic microbial communities obtained from a field study of two streams in the Chicago metropolitan area. In addition, the presence and effects of a widely used antimicrobial, triclosan, were studied both in the field and using the artificial stream facility located at Loyola University Chicago.

Our findings suggest that WWTP effluent significantly reduce both chemical and biological variation in the benthic ecosystems. These results raise questions about the impacts of anthropogenic ecosystem modifications and WWTPs on lotic ecosystems. Results also indicated that WWTPs were not significant point sources of triclosan, suggesting that non-point sources are more significant sources of triclosan into lotic ecosystems.  However, sediment triclosan concentrations correlated closely with the degree of urbanization of the surrounding habitat. Using model streams we were able to generate a triclosan resistant bacterial community that was similar in size to control streams from a single dosing of triclosan.

VITA

Bradley Drury attended Loyola University Chicago and earned a Bachelor of Science in Biology, with Honors, in 2009.
Currently, Bradley is an Instructor for ECC Foreign Language Institutes.  He lives in Kobe, Japan.

 ACKNOWLEDGMENT

The work in this thesis was supported by a grant to John J. Kelly and Emma Rosi-Marshall from the Illinois Sustainable Technology Center.  Thanks to Marty Berg and Timothy Hoellein for their technical assistance and to Domenic Castignetti and Timothy Hoellein for helpful comments on this thesis.  

COMMITTEE MEMBERS:

Dr. John Kelly 

Dr. Timothy Hoellein

Dr. Domenic Castignetti