Gschwend%20thesis.pdf

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This suggested an anthropogenic source related to summer recreational
activities for these large inputs.
An unknown ocmpound, probably an octatriene, was found in late
February and March. This material
may be related to the chemical
attractant utilized by Fucus spp. (Phaeophyta) and may represent a
biological signal.
Naphthalenes were most abundant after an oil spill and in
winter samples. Winter samples contained a greater abundance of naphtha-
lene, relative to the methyl naphthalenes, than did summer samples; this
suggests that more indirect sources are important in the winter and
thereby allow fractionation during transport of these homologues.
Pentadecane and heptadecane were the dominant n-alkanes observed.
Separate large concentration increases for these compounds were found in
the summer and the high "CPr" strongly suggests a biological source of
these compounds. Benthic algae are abundant at this time of year, have
been shown to contain these hydrocarbons (Youngblood et al., 1971;
Youngblood and Blumer, 1973), and consequently have been identified as
the probable sources.
C6-CIO straight chain aldehydes were found in all samples year-
round. These aldehydes, and longer chain homologs from Ci2-CI5' were
greatly increased in abundance in the late winter. The coincidence with
the Thalassiosira, nordenskioeldii bloom indicated that this phytoplankton,
or oxidation of the organic matter produced by this diatom, was the source
of these oxygenated volatiles.
Dimethyl di-, tri-, and tetrasulfides were found in the coastal
seawater. These polysulfides. may be formed by reaction of methyl
mercaptan and elemental sulfur, or from polysulfide metabolites of marine
organisms.