1. Assessing spatial impacts of historical pulp mill effluent on trophic dynamics in a coastal marine ecosystem using stable isotope (δ13C and δ15N) analysis.
- Author
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Fraser, Megan R., Walker, Tony R., Sherwood, Owen A., and Oakes, Ken D.
- Subjects
STABLE isotopes ,PULP mills ,STABLE isotope analysis ,MARINE ecology ,ECOSYSTEMS ,MUMMICHOG ,MYTILUS edulis ,ESTUARIES - Abstract
Boat Harbour, Nova Scotia was a tidal estuary that was converted into a wastewater treatment facility for pulp mill effluent in 1967. Treated effluent from Boat Harbour was discharged into the coastal Northumberland Strait, contributing significant nutrient and freshwater inputs into the coastal environment, potentially impacting local biogeochemistry and ecosystem structure. This study used stable isotope analysis of carbon (δ
13 C) and nitrogen (δ15 N) of representative taxa to assess spatial variability in nutrient sources and trophic dynamics. Results identified stable isotope variation with depleted δ13 C and δ15 N values in taxa near Boat Harbour. Blue mussel (Mytilus edulis) and mummichog (Fundulus heteroclitus) were the most suitable bioindicators for identifying variation in nutrient sources. Stable isotope signatures in this study may be reflective of residual pulp mill effluent-derived nutrients, differences in marine versus terrestrial nutrient sources, and a pronounced coastal salinity gradient. The present study defined the baseline nutrient conditions of the Northumberland Strait and will be useful in assessing the effectiveness of remediation activities. • δ13 C and δ15 N was analyzed in biota historically exposed to pulp mill effluent. • Depleted δ13 C and δ15 N observed near the former effluent outflow. • Salinity gradient and additional wastewater may influence stable isotope variation. • Depleted δ13 C near the former outflow corresponds to lower salinity values. • Mussels and mummichogs were suitable bioindicators for coastal nutrient dynamics. [ABSTRACT FROM AUTHOR]- Published
- 2024
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