Biogeochemical influences on the carbon isotope signatures of Lake Ontario biota

• Published in: Canadian journal of fisheries and aquatic sciences Vol. 56; no. 11; pp. 2211 - 2218
• Main Authors: Leggett, M F, Servos, M R, Hesslein, R, Johannsson, O, Millard, E S, Dixon, D G
• Format: Journal Article
• Language: English
• Published: 01.11.1999
• Subjects: Freshwater; North America, Ontario L; Canada, Ontario, Ontario L
• ISSN: 0706-652X; 1205-7533
• DOI: 10.1139/cjfas-56-11-2211

Particulate organic matter (POM), zooplankton, and benthic invertebrates were sampled seasonally at a midlake and east basin site in Lake Ontario. The delta super(13)C values of POM samples were compared with measurements of chlorophyll a concentrations, areal rates of primary productivity, concentrations of dissolved free CO sub(2) (CO sub(2(aq))), and the delta super(13)C of zooplankton and benthic invertebrates. The delta super(13)C of POM was significantly correlated with the concentration of CO sub(2(aq)) at the east basin site. No correlation was found between chlorophyll a concentrations, areal rates of primary productivity, and the delta super(13)C of POM. The delta super(13)C of zooplankton was not always similar to the delta super(13)C of the POM fraction collected, indicative of the complexity of food web interactions within the lower trophic levels. The delta super(13)C of benthic invertebrates feeding on the sediment surface was similar to that of POM produced prior to stratification, indicating the importance of the spring bloom as a food source for benthic primary consumers.