Zooplankton Measurements from the U.S. JGOFS Arabian Sea Process Study

A component of U.S. Joint Global Ocean Flux Study (JGOFS) is the
Arabian Sea Process Study. Eleven cruises took place aboard the R/V
Thomas G. Thompson for about sixteen months from October 1994 until
January 1996. These cruises provided seasonal coverage of the annual
monsoon and inter-monsoon cycles in the area southeast of Oman - from
where the cruises were staged. The monsoons of the Arabian Sea drive
a uniquely intense carbon cycling system, and it is the goal of JGOFS
to better understand the role of the oceans in global carbon cycling.

Zooplankton samples were collected using Multiple Opening\Closing Net
and Environmental Sensing System (MOCNESS) as well as Bongo nets. Tow
depths were typically 1000 meters (for MOCNESS) or 200 meters (for
Bongo). Typically a day and a night tow were taken at various
stations during four seasonally-spaced process cruises (TTN-043,
TTN-045, TTN-050, TTN-054). The samples were used to determine
mesozooplankton carbon biomass and displacement volume (dv).

Mesozooplankton carbon biomass (mmol C/m2) was determined by CHN
analysis (Roman) and by dry weight (Wishner & Gowing).

The mesozooplankton carbon biomass as determined by CHN analysis
(Roman) is available in size fractions of 64-200 microns and greater
than 200 microns.

The mesozooplankton dry weight biomass (Wishner & Gowing) is available
for size fractions of 200-500 microns, 500-1000 microns, 1000-2000
microns, and greater than 2000 microns. These data files are
organized either by depth zone or per net. Files of mesozooplankton
displacement volume (ml/m3) and wet weight biomass (mg/m3) are also
available.

Additionally, microzooplankton abundances and biomass are available
(Gowing & Garrison) for cruises TTN-050 and TTN-054. These include
heterotrophic nanoflagellates (excluding dinoflagellates),
heterotrophic dinoflagellates, non-loricate ciliates (including
plastidic oligotrichs), and tintinnids (ciliates).

Finally, zooplankton displacement volumes (cc/m3) are available
(Smith) from MOCNESS and Bongo tows for cruises TTN-039 (calibration
cruise), TTN-050 (summer monsoon), and TTN-054. Zooplankton dry
weight biomass (mg/m3) is available (Smith) from Bongo tows for cruise
TTN-054 in size fractions of 64-200 microns, 200-560 microns, 560-1050
microns, and greater than 1050 microns.

The data is public domain and can be retrieved on-line at
"http://usjgofs.whoi.edu/jg/dir/jgofs/"

[This information was obtained from U.S. JGOFS website at WHOI.]