Biofilm Complexity Controls Fine Particle Dynamics in Streams

Kevin Roche, William Hunter, Jennifer Drummond, Tom Battin, Fulvio Boano, Aaron Packman

Research output: Contribution to conferencePosterpeer-review

Abstract

Most models of riverine eco-hydrology and biogeochemistry rely upon bulk parameterization of fluxes. However, the transport and retention of carbon and nutrients in headwater streams is strongly influenced by biofilms (surface-attached microbial communities), which results in strong feedbacks between stream hydrodynamics and biogeochemistry. Mechanistic understanding of the interactions between streambed biofilms and nutrient dynamics is lacking. Here we present experimental results linking microscale observations of biofilm community structure to the deposition and resuspension of clay-sized mineral particles in streams. Biofilms were grown in identical 3 m recirculating flumes over periods of 14-50 days. Fluorescent particles were introduced to each flume, and their deposition was traced over 30 minutes. Particle resuspension from the biofilms was then observed under an increased stream flow, mimicking a flood event. We quantified particle fluxes using flow cytometry and epifluorescence microscopy. We directly observed particle adhesion to the biofilm using a confocal laser scanning microscope. 3-D Optical Coherence Tomography was used to determine biofilm roughness, areal coverage and void space in each flume. These measurements allow us to link biofilm complexity to particle retention during both baseflow and floodflow. The results suggest that increased biofilm complexity favors deposition and retention of fine particles in streams.
Original languageEnglish
Publication statusPublished - 15 Dec 2014
EventAmerican Geophysical Union Fall Meeting 2014 - San Francisco, United States
Duration: 15 Dec 201419 Dec 2014
http://fallmeeting.agu.org/2014/

Conference

ConferenceAmerican Geophysical Union Fall Meeting 2014
Abbreviated titleAGU 2014
Country/TerritoryUnited States
CitySan Francisco
Period15/12/201419/12/2014
Internet address

Fingerprint

Dive into the research topics of 'Biofilm Complexity Controls Fine Particle Dynamics in Streams'. Together they form a unique fingerprint.

Cite this