Farooq Azam and David C. Smith
Methodology for POC and PON measurements


Water from the CTD rosette was transferred to brown polyethylene or
polycarbonate bottles and shielded from light until filtration (within
two hours of sampling).  The bottles were rinsed with Milli-Q water
after each use and twice with sample before filling.  The water was
then filtered through combusted (4 hours at 480°C) Whatman GF/F
filters at a pressure differential of <150 mm Hg. Typically, 2 liters
of sample were filtered for water collected in the upper 250 m and 4
liters were filtered for water collected below 250 m.  The filters were
then stored at -80°C.

After the cruise, the filters were packed in dry ice and shipped to
Scripps Institution of Oceanography and stored at -80°C.  The
filters were then dried at 60°C overnight in the presence of HCl
and then shipped to the Bermuda Biological Station for Research were
they were analyzed by BATS personnel using the BATS/JGOFS protocols.