| Summary: | Measuring suspended sediment concentration (SSC) is both costly and labour intensive.
Temporal records of SSC are, however, of paramount importance in elucidating issues
relating to geomorphology, ecology and water quality. Rating curves, that relate SSC and
discharge by a simple linear regression function, are frequently employed by workers to
address the problems of recording SSC. Such functions, however, rarely account for more
than 50% of the variability in observed SSC. The aim of this thesis is to formulate subseasonal
predictive SSC models and to investigate hydrologic controls on proglacial
suspended sediment dynamics using data collected from a glacier-fed stream, Coast
Mountains, British Columbia.
In order to model proglacial SSC, the hydrologic season was initially divided into
nival, nival-glacial, glacial and autumn recession periods, according to sudden shifts in the
ratio of stream discharge between the glacierised and a neighbouring unglacierised catchment
of similar size and aspect. Multiple regression functions, to predict SSC, were then
developed for each period. These regression models incorporate a suite of easily measured
variables and are shown to reduce significantly, initial problems of autocorrelation,
heteroskedasticity and non-linearity of the SSC-discharge relationship. Analysis of the
significant parameters in the multiple regression models, the hysteretic relationship between
SSC and discharge, and downstream changes in SSC reveal that short-term, within channel,
storage of fine sediment may be an important control on proglacial suspended sediment
dynamics in this complex glaciofluvial lacustrine system. === Arts, Faculty of === Geography, Department of === Graduate
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