The big deal with little particles in aquatic and terrestrial ecosystems: nanomaterials in the environment
Speaker: Benjamin P. Colman, Duke University
Series: CEE Departmental Seminars
Location: Bowen Hall Auditorium
Date/Time: Monday, April 21, 2014, 12:15 p.m. - 1:30 p.m.
The ecology and biogeochemistry of ecosystems can be dramatically altered by contaminantdependent perturbations. Manufactured nanomaterials (1-100 nm) are an emerging class of contaminants that are increasingly entering the environment, yet little is known about their potential impacts. Due to their unique properties, nanoparticles are likely to differ from well-studied contaminants in their transport, reactivity, and organismal uptake. Silver nanoparticles are of particular concern because they are used in consumer products for their potent biocidal properties. They are also predicted to enter the environment, primarily through land-application of biosolids and effluent release from wastewater treatment facilities. This talk will describe the findings of microcosm and mesocosm experiments designed to examine the fate and impacts of silver nanoparticles in simulated ecosystems. In both aquatic and terrestrial ecosystems, silver nanoparticles markedly altered plant and microbial abundance, composition, and activity, leading to changes in trace gas fluxes. At the same time, ecosystems altered nanoparticle size, toxicity, and fate. Focusing on manufactured nanoparticles has also provided new insights into the role of ubiquitous natural nanoparticles in ecosystems.
Benjamin P. Colman received his Ph.D. in 2009 in Ecology, Evolution, and Marine Biology from the University of California, Santa Barbara. Currently, he is a postdoctoral associate with Dr. Emily Bernhardt at Duke University, and a member of the Center for Environmental Implications of NanoTechnology (CEINT). Ben's research interests range from studying the fundamental controls of energy and nutrient cycling in terrestrial and aquatic ecosystems, to understanding how chemical perturbations (N deposition, engineered nanomaterials, saltwater intrusion) alter these controls. The approach Ben takes in his work as a member of CEINT is directed towards understanding the environmental impacts of nanomaterials by studying them through the lenses of ecosystem ecology, microbial ecology, and biogeochemsitry. Simultaneously, he is also working to better understand the impacts of ecosystems on the engineered nanomaterials in terms of their fate and transformations, which ultimately feeds back to determine their impacts.