The Utility of Microfossils in Geoarchaeology: A Case Study from Lake Simcoe, Ontario and Methodological Considerations

Abstract

Eutrophication has been an issue in Lake Simcoe since the 1970s, stressing aquatic wildlife, notably economically-important cold water fish. Non-pollen palynomorphs (NPP) are more sensitive proxies of water quality than sedimentary phosphorus, and have a higher fossilization potential than mineralized microfossils like diatoms, although some, notably desmids, were shown to be sensitive to acetolysis. Algal palynomorphs record cultural eutrophication since European settlement at all three sites in a north-south transect (particularly at the southern site Cook’s Bay) and similar NPP assemblages record eutrophication below the Ambrosia (ragweed) rise in cores from the main basin and Smith’s Bay. This event has been attributed to the Wendat (Huron) occupation of Wendake (Huronia) that ended in the mid-seventeenth century, an attribution supported the by increases in micro-charcoal, likely from controlled fires and the presence of palynomorphs associated with agriculture.