Gschwend%20thesis.pdf

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polysulfide volatiles. Particularly attractive candidates are compounds
like the bis-(3-oxoundecyl) di-, tri- and tetra sulfides or bis-(3-acetoxyundec-
5-enyl) disulfide found in the red alga, Dictyopteris spp. (Roller et al.,
1971; Moore, 1971; Moore et al., 1972).
A simple calculation suggests the importance of these polysulfides to
the sulfur cycle. The seawater at CD contained about LO ng-S/kg in the form
of these polysulfides; this represented a standing stock of 20 ~g_S/m2. If
this material was swept into the atmosphere in about 3-4 days
.
(Schwarzenbach
2
et al., 1978), this amounts to the local introduction of about 2 mg-S/m /yr
to the air. This figure is similar to the 2 mg/m2/yr calculated for H2S
and the 6-10 mg/m2/yr for dimethyl sulfide found in the coastal region of
Chesapeake Bay (Maroulis and Bandy, 1977). However, a global biological
source of about 130 mg-S/m2/yr is needed to balance the sulfur cycle (Friend,
1973) .
Other Volatile Organic Compounds. Two halogenated volatiles were observed
in seawater at CD. The first was tetrachloroethylene at about lng/kg.
This value is similar to that reported for the Northeast Atlantic of 0.5
ng/kg, but much lower than the concentration in Liverpool Bay (l20 ng/kg)
(Murray and Riley, 1973). The source of this compound was most likely
anthropogenic as it
et al., 1975).
is heavily used in a direct disperal manner (McConnell
Bromoform (CHBr 3) was also found, particularly in the summer. The
source of this compound was probably the benthic algae (chapter 5 and
Burreson et al., 1975).
Total Volatile Organic Compounds. Figure 3-23 shows the total volatile
organic compound concentrations over a six-month period as measured by