Marine influences on coastal lakes in British Columbia and Alaska: Paleolimnological reconstructions of sockeye salmon dynamics and sea level changes

In coastal environments, interactions between marine and freshwater systems are common. The objectives of this thesis were to examine two such influences in British Columbia and Alaska using multi-proxy paleolinmological techniques in an attempt to: (1) track sockeye salmon population dynamics over the last ∼200 years; and (2) track changes in sea level on the west coast of Vancouver Island during the last millennium.; The decomposition of salmon carcasses in oligotrophic nursery lakes enriches lake sediments with marine-derived nutrients and 15N. These inputs, known as salmon signals, can be tracked using paleolimnology. Diatoms, chrysophytes, geochemical data, and stable isotope indicators were examined in 210Pb-dated sediment cores from three coastal sockeye salmon nursery lakes in B.C. and Alaska.; A decrease in relative sea level on the west coast of Vancouver Island was also recorded using paleolimnological techniques.; Finally, microfossil indicators, stable isotopes and geochemical data were analysed in a sediment core from a control lake (Tsusiat Lake); no changes were recorded in the lake over the last ∼180 years. (Abstract shortened by UMI.)...