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Chemical Oceanography, 4th Edition
that is often referred to as an “unresolved complex mixture.” Thin- layer chromatography coupled to flame ionization detection (FID) is a promising new technique that can
be used to separate the DOM from seawater into compound classes such as lipids and
base mobile (amines, alcohols, ketones) and acid mobile fractions. The large number of
unidentified organic compounds as seen on a chromatogram is indicative of how much
we still have to learn before we can hope to begin to form realistic models of the organic
chemistry of the oceans. Mopper and Stahovec (1986) used HPLC (high- performance
1.5
Downward Doc Flux (Pg C yr
–1 )
1
0.5
0
1500
1000
500
0
0
0.05
0.1
Doc/Poc Flux Ratios
0.15
0.2
Depth (m)
Figure 9.41
DOC and POC flux ratios to the deep oceans. (From Hansell, D.A., et al., Oceanography, 12, 203–211, 2009. With
permission.)
12
10
8
6
4
2
0
30°S
30°N
60°N
EQ
60°S
Figure 9.42
POC and DOC export to the world oceans. (From Hansell, D.A., et al., Oceanography, 12, 203–211, 2009. With
permission.)