HR: 1330h
AN: NB33B-05    [Abstracts]
TI: Nutrient Status and Criteria Development for the Saint John River, Canada, Using a Weight of Evidence Approach
AU: Culp, J M
EM: Joseph.culp@ec.gc.ca
AF: National Water Research Institute, Environment Canada, Dept. of Biology, University of New Brunswick 10 Bailey Drive , Fredericton, NB E3B 5A3 Canada
AU: Culp, J M
EM: Joseph.culp@ec.gc.ca
AF: Canadian Rivers Institute, Dept. of Biology, University of New Brunswick 10 Bailey Drive, Fredericton, NB E3B 5A3 Canada
AU: * Luiker, E A
EM: Eric.Luiker@ec.gc.ca
AF: National Water Research Institute, Environment Canada, Dept. of Biology, University of New Brunswick 10 Bailey Drive , Fredericton, NB E3B 5A3 Canada
AU: Noel, L
AF: Canadian Rivers Institute, Dept. of Biology, University of New Brunswick 10 Bailey Drive, Fredericton, NB E3B 5A3 Canada
AU: Curry, A R
AF: Canadian Rivers Institute, Dept. of Biology, University of New Brunswick 10 Bailey Drive, Fredericton, NB E3B 5A3 Canada
AU: Hryn, D
AF: National Water Research Institute, Environment Canada, Dept. of Biology, University of New Brunswick 10 Bailey Drive , Fredericton, NB E3B 5A3 Canada
AU: Heard, K
AF: Canadian Rivers Institute, Dept. of Biology, University of New Brunswick 10 Bailey Drive, Fredericton, NB E3B 5A3 Canada
AB: The Saint John River is the largest in Maine/New Brunswick (673 km in length, draining 55,000 km²) with a history of natural resource use and nutrient effluent release to the watershed since the late 17^th century. Our objective was to obtain a basic understanding of the contemporary nutrient conditions of the non-tidal portion of the river in relation to historical conditions, and to consider how the contemporary river is affected by point and non-point source nutrient loadings. The study included review of historical provincial and federal water quality databases dating back to the 1960s. Current water quality monitoring programs have focused on nitrogen (nitrite, nitrate, ammonia, TKN), phosphorus (total, dissolved, and soluble reactive phosphorus), DIC/DOC, and biomass of periphyton and phytoplankton. To determine nutrient limitation, nutrient diffusing substrate studies were conducted in river reaches of known nutrient enrichment. Oxygen stable isotopes were also used to provide information on the photosynthesis to respiration ratio. A weight of evidence approach combining the results of these studies was used to determine trophic status of river reaches and to highlight areas of eutrophication. From this information nutrient criteria for the Saint John River will be proposed.
DE: 0400 Biogeosciences
DE: 1803 Anthropogenic effects
DE: 1845 Limnology
DE: 1871 Surface water quality
SC: North American Benthological Society [NB]
MN: 2005 Joint Assembly