Relationships Between Sediment Chemistry and Postglacial Production Rates in a Small Canadian Lake

✍ Scribed by Mr. R. W. Adams; Dr. H. C. Duthie

• Book ID: 102869027
• Publisher: John Wiley and Sons
• Year: 1976
• Tongue: English
• Weight: 1016 KB
• Volume: 61
• Category: Article
• ISSN: 1434-2944
• DOI: 10.1002/iroh.19760610103

✦ Synopsis

Abstract

In a chemical investigation of the sediments of a small meromictic lake in southwestern Ontario, Canada, the hypolimnion had evidently become increasingly reductive over most of the postglacial as the lake gradually filled in. The ratio of phosphorus to organic matter tended to fall, suggesting that an increasing proportion of precipitated phosphorus had become mobile and re‐available to the lake's ecosystem. Productivity, as inferred from fossil pigment analysis, tended to increase over the postglacial, and there is no evidence for a prolonged period of trophic equilibrium. Maximum production rates were correlated with efficient phosphorus diagenesis. The lake evidently became meromictic around 900 BP (before present) and this was associated with a sulphide producing monimolimnion and decreased productivity. Cultural practices in the watershed around 140 BP increased inorganic sedimentation and further reduced productivity.