Light-dependence of the metabolic balance of a highly productive Philippine seagrass community

E. Gacia*, H. Kennedy, C. M. Duarte, J. Terrados, N. Marbà, S. Papadimitriou, M. Fortes

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

28 Scopus citations


Seagrass meadows are important primary producers in SE-Asia coastal areas that are increasingly threatened by human activities resulting in a deterioration of the underwater light environment. The resilience of seagrass meadows to decreasing light availability should be approached in an integrative manner, because they shelter complex communities of primary and secondary producers. The aim of this study was to measure the in situ metabolism of a seagrass community under different levels of light availability following changes in the water column dissolved oxygen (DO) and dissolved inorganic carbon (DIC), the sediment redox potential and seagrass production. Net community production (NCP) and respiration were measured along two diel cycles to produce a balance of NCP under different light treatments. On a daily basis, at full irradiance, the community metabolism presented a net production which was close to zero, with values of -7.75 to 16.6 mmol O2 m-2 day -1 for DO, and -56.8 to 22.7 mmol C m-2 day-1 for DIC in the first and second incubation runs, respectively. Compensation irradiance for the NCP was thus found to be close to 80% of the present light availability. Shading resulted in a general decrease in the sediment redox potential, while the initial redox potential had not recovered 6 days after exposure to full sunlight. This community appears to be in a fragile equilibrium with the environment, and any minor decrease in the water transparency would lead to a shift from an autotrophic to a heterotrophic system.

Original languageEnglish (US)
Pages (from-to)55-67
Number of pages13
JournalJournal of Experimental Marine Biology and Ecology
Issue number1
StatePublished - Mar 9 2005
Externally publishedYes

Bibliographical note

Funding Information:
This research was funded by project PREDICT (contract IC18-CT98-0292) of the INCO program of the European Commission. We are grateful to Paul Kennedy, Cristina Barrón, Napo Cayabyab, Zayda Halum, Jack Rengel, Roger Savella and Tu Thi Lan Houng for their help during the fieldwork. We also thank O. Perdersen and T. Greve for the data and plot on the continuous monitoring of the water column conditions during the 2nd incubation day. Lars K. Nielsen and Claus Ankjaergaard also collaborated ‘coring’. Comments and criticisms of two anonymous reviewers were very helpful and significantly improved the quality of the manuscript. [RW]


  • Benthic chamber
  • Community
  • Light
  • Metabolism
  • Seagrasses
  • Tropical

ASJC Scopus subject areas

  • Ecology, Evolution, Behavior and Systematics
  • Aquatic Science


Dive into the research topics of 'Light-dependence of the metabolic balance of a highly productive Philippine seagrass community'. Together they form a unique fingerprint.

Cite this