Bulk elemental and biochemical yields in samples collected across the benthic boundary layer (BBL) in the Northeast Atlantic indicated the BBL to be a key site of organic matter (OM) alteration and played a pivotal role in determining the organic carbon: surface area ratio (OC: SA) ratio of material deposited in the sediments in this region. Evidence for the seasonal nature of OM inputs to the BBL in the Northeast Atlantic was found in two of the three investigated sites. The seasonal deposition of material associated with the spring bloom led to the presence of a substantial layer of phytodetritus material at one site. Although this material was not rich in OC, it contained elevated yields of labile biochemicals that suggested the potential importance of such material to deep-sea benthic nutrition. The majority of OM within the sediments in the deep Northeast Atlantic appeared to be sorbed to mineral grains displaying SA-normalised OC loadings below those typically observed on continental margins (i.e. <0.5<i> </i>mg QC m<sup>-2</sup>) indicating that OM remineralisation processes are extremely efficient in this region. An investigation into the possible influences on OC preservation and burial in the Northeast Atlantic and in other diverse continental margin sediments, suggested that only the length of time that sedimentary OM was exposed to oxic porewaters displayed a consistent relationship with sediment OC: SA ratios and OC burial efficiencies. Sediment oxygen exposure time, therefore, appear to be a primary control on OM burial.
Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:651588 |
Date | January 2002 |
Creators | Good, Emily Irene |
Publisher | University of Edinburgh |
Source Sets | Ethos UK |
Detected Language | English |
Type | Electronic Thesis or Dissertation |
Source | http://hdl.handle.net/1842/13931 |
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