Variations in carbon fractions within a dimictic and a meromictic basin of the Junius Ponds, New York

SUMMARY. 1. The Junius Ponds, a unique series of proximate glacial kettle basins located between the cities of Rochester and Syracuse. New York, U.S.A., contain basins of dimictic and meromictic nature. This study focused upon differences in partitioning of total inorganic carbon (TIC), paniculate organic carbon (POC), and dissolved organic carbon (DOC) within the dimictic Junius Pond 7 (JP7, ∼8m) and the meromictic Junius Pond 5 (JP5, ∼17m).
2. For TIC, variations with depth were much greater in JP5 than in JP7. However, seasonal variations were greater in JP7 than in JP5. We attribute these variations to differences in the mictic nature of the basins.
3. Concentrations of POC were substantially less in the relatively clear mixolimnion of JP5 than in the epilimnion of JP7. Distinct POC layers formed at the oxic-anoxic boundary in both basins during late summer.
4. The lower monimolimnion of JP5 is believed to have the warmest water occurring under ice (8.2–8.6°C) of any natural body of water in the continental United States east of the Mississippi River. The monimolimnetic region of JP5 has unusually low DOC:POC ratios of ≤1:l.