Coupling of hydrodynamical, biological, and geochemical processes in streambeds

350 210 Stroud Water Research Center

Packman, A.I., T.J. Battin, and J.D. Newbold. 2003. Archives of Hydro-Engineering and Environmental Mechanics 50:107–123.

No DOI available.


Recent interest in the effects of streambed and near-subsurface (benthic and hyporheic) processes on stream ecosystems has motivated study of the hydrodynamics of stream-subsurface interactions. Hydrodynamic transport places an important control on the delivery of reactive species such as contaminants and ecologically-relevant substances such as nutrients to the benthic and hyporheic zones. Conversely, biological processes such as biofilm growth and physicochemical processes such as colloid deposition can alter the transport environment within sedimentary systems. Multiple feedbacks between biological, chemical, and transport processes make these interfacial sedimentary environments very complex. Experimental results are presented to illustrate the feedbacks between hydrodynamic stream-subsurface exchange, biofilm development, and fine particle deposition. These studies demonstrate that a comprehensive interdisciplinary approach is required to assess even the most basic dynamic processes in these systems, such as the evolution of interfacial fluxes over time. We suggest that it is useful to consider these processes to be biophysicochemical in nature. That is, in such complex environmental systems, it is misleading to attempt to consider processes in isolation; rather, understanding of system dynamics can only come from an integrated approach that considers feedbacks among and between biological, physical, and chemical processes.


NSF Award No. DEB-0096276. Title: LTREB: Stream ecosystem structure and function within a maturing deciduous forest. Duration: August 1998–July 2003. Principal Investigator: L. A. Kaplan. Co-principal investigators: B. W. Sweeney, T. L. Bott, J. D. Newbold, J.K. Jackson, and L. J. Standley.