Chironomid-based paleosalinity records in southern British Columbia, Canada: a comparison of transfer functions

Chironomid remains from Big Lake, British Columbia were analysed and paleos alinities were estimated using a pre-existing transfer function and several developed using new regression methods. A two component partial-least-squa res model (PLS-2) had the highest coefficient of determination (R-(Jackknif ed)(2) = 0.75) and lowest root-mean-squared error- of-prediction (RMSEP). A s compared to the pre-existing model, it was also less sensitive to the inf luence of rare taxa. Nevertheless, the marginally larger R-(Jackknifed)(2) and lower RMSEP do not clearly identify a single best model. The models wer e applied to Big, Mahoney and Kilpoola lakes, revealing the sensitivity of paleosalinity inferences to model selection. A synopsis of chironomid-based paleosalinities in British Columbia and their correspondence with other pa leoclimatic data are presented and discussed.