| |
Presented at the NABS Annual meeting, Pittsburgh, Pennsylvania, 2002
in Periphyton
PERIPHYTON DYNAMICS IN THE JACKSON RIVER (VA): A MULTI-DISCIPLINARY STUDY.
D.J. Velinsky1, C.A. Flinders1, D.F. Charles1, T.L. Bott2, T.W. Gallagher3, D.D. Hart1, and R.L. Thomas1. 1Patrick Center for Environmental Research, The Academy of Natural Sciences, Philadelphia, Pennsylvania, USA, 19103, 2Stroud Water Research Center, Avondale, Pennsylvania, USA 19311, 3HydroQual, Inc. Mahwah, New Jersey, USA 07430
Few comprehensive studies have attempted to model the dynamics of benthic algae in an anthropogenically-altered river. The Jackson River (Covington, VA) is a regulated river that receives nutrient-enriched effluent from industrial sources and experiences high algal biomass downstream from the facilities. A multi-disciplinary, multi-year study (including monitoring of algal biomass and taxonomic composition, periphyton metabolism and pulsed-flow experiments, and stable isotope analyses) is being conducted to develop a model of periphyton-oxygen-nutrient dynamics for the Jackson River. Algal chl a is greatest within 10 km downstream of the facilities. Biomass varies temporally with the greatest chl a concentration typically occurring during fall months. Chamber studies to determine periphyton metabolic rates show variable effects of nutrient concentration, especially nitrogen. Pulsed-flow experiments show a significant negative relationship between algal biomass and treatment velocity, with velocity explaining more than half the variation in algal biomass. Stable isotopes of C and N can be used to follow the distinct signature of the effluent solids km(s) downstream during base-flow and appear to be incorporated into the benthic community. Results of these studies will be used to develop a comprehensive periphyton model and will aid in developing effluent guidelines in order to maintain ecosystem health.
|
|
