Fjord Systems and Archives

Fjords are glacially over-deepened, semi-enclosed marine basins, but are often neglected as a sedimentary realm. They represent the transition from the terrestrial to the marine environment and as such have the potential to preserve evidence of environmental change. Typically most fjords have been glaciated a number of times and some high-latitude fjords still possess a resident glacier. The stratigraphic record in fjords largely preserves a glacial–deglacial cycle of deposition. Sheltered water and high sedimentation rates potentially make fjords ideal depositional environments for preserving continuous records of climate and environmental change with high temporal resolution. Fjords are also referred to as miniature oceans providing the unique opportunity to study marine processes in great detail. With predictions of warming climates, changing ocean circulation and rising sea levels, this volume is a timely look at these environmentally sensitive coastlines.
Sediment fluxes and carbon budgets in Loch Creran, western Scotland
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Published:January 01, 2010
Abstract
Sea lochs are regions where riverine and marine organic carbon (OC) undergoes decomposition, deposition or transportation to shelf slopes and the deep sea. According to the OC budget presented here, discharge from River Creran (1.44×106 kg a−1) and phytoplankton material (0.89×106 kg a−1) make up a significant input of OC to Loch Creran while 0.67×106 kg a−1 OC is from other sources. A total of 1.28×106 kg a−1 OC is deposited in the loch and 1.14×106 kg a−1 OC is oxidized in the water column. Discharge to the Lynn of Lorn consists of 0.58×106 kg a−1 OC. Hence Loch Creran is a sink for OC where 42.7% of the total OC input is buried and 38% and 1.7% decomposed in the water column and subsurface sediments, respectively. River Creran contributes 63% labile and 37% refractory organic matter to the loch. More than 95% of each of the total OC, lignin and organic matter deposited onto the surface sediments is buried in the subsurface sediments. Seventy-five percent of the total organic matter decomposed in the water column is labile. Output to Lynn of Lorn consists of 54.6% refractory organic matter.