Gschwend%20thesis.pdf

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source, air concentrations in this region would have to be about 1-2
ng/l air (K ~ 0.34). This value may be compared with the 3-5 ng/l
air measured near Cape Cod (chapter 4) and in rural areas of Florida
(Lonneman et al., 1978).
Station 4 in the Peru upwelling region demonstrated two unusual
features. The sum of the 5-m, 20-m, and 100-m concentrations for the
meta + para xylenes was much lower than that for any other station.
Also, the deep sample from this station revealed an anomolously high
concentration. The fact that surface water at this station also
shows a nutrient minimum suggests that the production of large numbers
of phytoplankton cells may have caused additional removal from
seawater of these aromatics either via adsorption or absorption.
Subsequent sedimentation and remineralization of this biogenic material
on the bottom may have caused the unusually high concentration of
meta + para xylene in the 4/340 m sample. This injection of aromatic
hydrocarbons to deep water may also explain the background levels
(0( 2 ng/kg) found in the other deep water samples from this region.
Specific Volatiles: unknown (ro 108)