Contribution of a dense population of the brittle star Acrocnida brachiata (Montagu) to the biogeochemical fluxes of CO2 in a temperate coastal ecosystem
Davoult, D.; Harlay, J.; Gentil, F. (2009). Contribution of a dense population of the brittle star Acrocnida brachiata (Montagu) to the biogeochemical fluxes of CO2 in a temperate coastal ecosystem. Est. Coast. 32(6): 1103-1110. dx.doi.org/10.1007/s12237-009-9216-2 In: Estuaries and Coasts. Estuarine Research Federation: Port Republic, Md.. ISSN 1559-2723; e-ISSN 1559-2731, more |  |
| Author keywords | Calciumcarbonate; Secondary production; Respiration; CO(2) fluxes; |
| Authors | | Top | - Davoult, D.
- Harlay, J., more
- Gentil, F.
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| Abstract | The production of organic matter and calcium carbonate by a dense population of the brittle star Acrocnida brachiata (Echinodermata) was calculated using demographic structure, population density, and relations between the size (disk diameter) and the ash-free dry weight (AFDW) or the calcimass. During a 2-year survey in the Bay of Seine (Eastern English Channel, France), organic production varied from 29 to 50 g(AFDW) m-2 year-1 and CaCO3 production from 69 to 104 g(CaCO3) m-2 year-1. Respiration was estimated between 1.7 and 2.0 mol(CO2) m-2 year-1. Using the molar ratio (psi) of CO2 released: CaCO3 precipitated, this biogenic precipitation of calcium carbonate would result in an additional release between 0.5 and 0.7 mol(CO2) m-2 year-1 that represented 23% and 26% of total CO2 fluxes (sum of calcification and respiration). The results of the present study suggest that calcification in temperate shallow environments should be considered as a significant source of CO2 to seawater and thus a potential source of CO2 to the atmosphere, emphasizing the important role of the biomineralization (estimated here) and dissolution (endoskeletons of dead individuals) in the carbon budget of temperate coastal ecosystems. |
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