Accumulation and export of dissolved organic carbon in surface waters of subtropical and tropical Pacific Ocean

被引:0
作者
Taki M. [1 ]
Suzuki Y. [1 ]
机构
[1] Graduate School of Sci./Engineering, Shizuoka University, Shizuoka 422-8529
关键词
Accumulation; Dissolved organic carbon; Export; Subtropical and tropical Pacific Ocean; Surface water;
D O I
10.1023/A:1021267922702
中图分类号
学科分类号
摘要
Dissolved organic carbon (DOC) concentrations in surface waters of the Pacific Ocean during October-November, 1995, were determined using a high-temperature combustion method. The DOC in the surface mixed-layer was approximately homogeneous with a concentration between 55 and 89 μmol C 1-1. This homogeneity indicates that there is a strong control of the vertical distribution of DOC by mixing processes. The DOC concentrations in the mixed-layer in the subtropical region were up to 27 μmol C 1-1 higher than in the tropical region. This difference reflects the subtropical accumulation and the tropical export of DOC. There is a significant positive correlation between DOC and chlorophyll a concentrations in the mixed-layer of the North Pacific subtropical region, suggesting that phytoplankton is the primary source of DOC accumulated in this region. Calculations using simple box models suggest that DOC export in the tropical region (0-50 m depth, 10°N-10°S, along 160°W) occurs primarily by poleward advection at a rate of 0.5-3 mmol C m-2day-1. A comparison with estimates of the export rate of particulate organic carbon published in previous studies leads us to conclude that DOC export may contribute less to the carbon budget in the tropical region than has recently been supposed.
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页码:631 / 646
页数:15
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  • [1] Archer D., Peltzer E.T., Kirchman D.L., A timescale of dissolved organic carbon production in equatorial Pacific surface waters, Global Biogeochem. Cycles, 11, pp. 435-452, (1997)
  • [2] Bacastow R., Maier-Reimer E., Dissolved organic carbon in modeling oceanic new production, Global Biogeochem. Cycles, 5, pp. 71-85, (1991)
  • [3] Bacon M.P., Cochran J.K., Hirschberg D., Hammar T.R., Fleer A.P., Export flux of carbon at the equator during the EqPac time-series cruises estimated from <sup>234</sup>Th measurements, Deep-Sea Res. II, 43, pp. 1133-1153, (1996)
  • [4] Barber R.T., Chavez F.P., Biological consequences of El Nino, Science, 222, pp. 1203-1210, (1983)
  • [5] Brady E.C., Bryden H.L., Estimating vertical velocity on the equator, Oceanol. Acta, 6, pp. 33-37, (1987)
  • [6] Bryden H.L., Brady E.C., Diagnostic model of the three-dimensional circulation in the upper equatorial Pacific Ocean, J. Phys. Oceanogr, 15, pp. 1255-1273, (1985)
  • [7] Carlson C.A., Ducklow H.W., Dissolved organic carbon in the upper ocean of the Central equatorial Pacific Ocean, 1992: Daily and finescale vertical variations, Deep-Sea Res. II, 42, pp. 639-656, (1995)
  • [8] Carlson C.A., Ducklow H.W., Michaels A.F., Annual flux of dissolved organic carbon from the euphotic zone in the Northwestern Sargasso Sea, Nature, 371, pp. 405-408, (1994)
  • [9] Carr M.-E., Oakey N.S., Jones B., Lewis M.R., Hydrographic patterns and vertical mixing in the equatorial Pacific along 150°W, J. Geophys. Res, 97, pp. 611-626, (1992)
  • [10] Carr M.-E., Lewis M.R., Kelley D., A physical estimate of new production in the equatorial Pacific along 150°W, Limnol. Oceanogr, 40, pp. 138-147, (1995)