Is DOC the main source of organic matter remineralization in the ocean water column?
In: Journal of Marine Systems. Elsevier: Tokyo; Oxford; New York; Amsterdam. ISSN 0924-7963; e-ISSN 1879-1573, more
Also appears in:Djenidi, S. (Ed.) (1996). The Coastal Ocean in a Global Change Perspective. Journal of Marine Systems, 7(Special Issue 2-4). Elsevier: Amsterdam. 117-438 pp., more
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| Authors | | Top |
- Lefèvre, D.
- Denis, M.
- Lambert, C.E.
- Miquel, J.C.
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| Abstract |
Recent interpretations of carbon flux data and deep-sea processes have led to a reconsideration of the role of dissolved organic carbon (DOC) in supporting water column remineralization and other mid-water biogeochemical transformations (Suzuki et al., 1985; Cho and Azam, 1988; Karl et al., 1988; Christensen et al., 1989; Naqvi and Shailaja, 1993). To date, there have been no direct comparisons of particulate carbon flux data with water column metabolic rates. Here, for the first time, particulate carbon flux and respiratory electron transport activity (from which metabolic CO2 production is derived), have been monitored simultaneously for one year in the same area of the northwestern Mediterranean Sea. In the aphotic layer (200-1000 m), particulate organic carbon (POC) can support only 20% of the overall organic matter remineralization. Remineralization rates are consistent with recent calculations of DOC exported from the euphotic layer in this area, confirming the vital importance of DOC in maintaining deep-water metabolism. This finding would apply to other regions of mesotrophic and oligotrophic production and thus affect our understanding of carbon recycling in the water column, new production and O2 utilization. |
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