Similar rapid response to phytodetritus deposition in shallow and deep-sea sediments
Moodley, L.; Middelburg, J.J.; Soetaert, K.; Boschker, H.T.S.; Herman, P.M.J.; Heip, C.H.R. (2005). Similar rapid response to phytodetritus deposition in shallow and deep-sea sediments. J. Mar. Res. 63(2): 457-469 In: Journal of Marine Research. Sears Foundation for Marine Research, Yale University: New Haven, Conn.. ISSN 0022-2402; e-ISSN 1543-9542, more | |
Keywords | Marine/Coastal; Brackish water |
Abstract | The short-term benthic response to an input of fresh organic matter was examined in vastly contrasting benthic environments (estuarine intertidal to deep-sea) using 13C-labeled diatoms as a tracer of labile carbon. Benthic processing was assessed in major compartments through 13C-enrichment in σCO2, in bacteria-specific phospholipids and in fauna tissue. A rapid response was evident in all environments. Under warm bottom water (14-18°C), similar quantities of the added carbon were respired within 24 hours in shallow and deep-sea sediments. However, the speed and magnitude of respiration were strongly reduced under low bottom water temperature (4-6°C), both in a shallow and a deep-sea site. Rapid carbon respiration even in deep-sea sediments almost devoid of fauna highlights the key role of bacteria, the most ubiquitous benthic component, in this short-term respiration of fresh organic matter. However, when present, fauna rapidly ingest algal material, thereby increasing the amount of carbon processed and directly extending carbon flow pathways. |
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