Table 1. Isotope and Concentration Measurements of Suspended POC and DIC Collected During the Amazon Cruise in November 1991a Stn Btm Dep Depth, m Coll. Type Salinity,permil UCID [POC], microg/L Delta14C POC Mean Delta14C +/-,permil delta13C POC UCID [DIC], microM Delta14C DIC Delta13C DIC 1 <4m 0.5 pump 0.40 448 -145 -145 6 -25.6 1778 374 120 -11 2 10 0.5 Go-flo 4.67 430 628 -167 -164 5 -24.8 1768 563 100 -7.9 2 1864 -160 -25.8 2 1865 -164 -25.9 3 10 0.5 Go-flo 20.78 527 635 -251 -222 20 -25 1770 1386 103 -2 3 1866 -207 -25.2 3 1867 -208 -25.3 4 10 0.5 Go-flo 22.00 445 281 -201 -200 5 -24.2 1765 1427 99 -1.5 4 0.5 1868 -199 -25.4 5 10 0.5 Go-flo 26.94 446 282 -184 -170 15 -23.6 1773 1718 110 -0.2 5 1869 -156 -24.2 6 812 10.0 pump 35.01 541 82 82 5 -22.1 1775 2051 88 1.8 7 3197 100.0 Go-flo 535 -130 30 nd 1776 2179 56 7a 3197 10.0 Go-flo 33.79 529 30 -21.2 1766 1955 63 0.7 9 4549 10.0 Go-flo 34.05 483 28 77 77 20 -21.5 1771 1983 86 1.7 10 4147 10.0 Go-flo 35.21 1777 2048 116 1.6 10 10.0 1779 94 1.8 11 4145 10.0 pump 33.78 526 37 13 13 5 -19.9 12 4145 10.0 Go-flo 33.40 484 28 112 112 20 1767 1941 94 1.7 13 4145 100.0 Go-flo 528 -112 20 nd 1772 2185 51 14 4145 10.0 Go-flo 32.64 1769 1911 91 1.6 15 4145 10.0 Go-flo 35.03 447 22 95 95 20 -19.9 1764 2014 89 2.0 aSamples from 100 meter depth are underlined, and laboratory identification numbers are italicized.