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Updated: Jul 2, 2026

Physiological Characterization of the Coral Holobiont Using a New Micro-Respirometry Tool
Published on: April 28, 2023
Low community photosynthetic quotient in coral reef sediments
Dorothée Taddei1, Pascale Cuet, Patrick Frouin
1ECOMAR, Université de la Réunion, avenue René-Cassin, 97715 Saint-Denis de la Réunion, France. taddei@univ-reunion.fr
Abstract:
Fluxes of dissolved inorganic carbon and oxygen at the water-sediment interface were measured at eight coral reef stations (Indian Ocean) in summer and winter. The dark fluxes provided the community respiratory quotient (CRQ = dissolved inorganic carbon release / oxygen uptake) and the diurnal fluxes corrected from the dark fluxes gave the community photosynthetic quotient (CPQ = oxygen gross release / dissolved inorganic carbon gross uptake). The CRQ and the winter CPQ were not significantly different from 1. Summer CPQ (0.79; SD 0.02) was significantly lower than 1 due to the combined effect of the daily evolution of the community respiration and the discrepancy between the daily evolution in community oxygen respiration and community carbon respiration. These results highlight the importance of measuring simultaneously the benthic community production and respiration for long term integrated data sets, instead of the traditional daily or seasonal budget calculations from limited measures of community respiration.
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