Skip Navigation

This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrowRequest Permissions
Google Scholar
Right arrow Articles by Gomes, H. D. R.
Right arrow Articles by Parulekar, A.H.
Right arrow Search for Related Content
PubMed
Right arrow Articles by Gomes, H. D. R.
Right arrow Articles by Parulekar, A.H.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

JOURNAL OF PLANKTON RESEARCH | VOLUME 14 | NUMBER 9 | PAGES 1307-1329 | 1992
© Oxford University Press

research-article

Size-fractionated biomass, photosynthesis and dark CO2 fixation in a tropical oceanic environment

Helga Do R. Gomes, Joaquim I. Goes and A.H. Parulekar

National Institute of Oceanography Dona Paula, Goa 403 004, India

Received on January 29, 1991; accepted on April 23, 1992 This study examines the spatial distribution and size structure of phytoplankton biomass and productivity in relation to the vertical structrure of the Andaman Sea (northeastern Indian Ocean). This region was characterized by low concentrations of nutrients and high levels of insolation. Nitrogen availability appeared to control overall productivity with nitrate-based ‘new’ production accounting for 8–24% of the total primary production. Euphotic column chlorophyll (chl a) averaged 52.5 mg m–2 of which a major portion was located as a subsurface chl a maximum (SCM) at ~60–80m. Net, nano and picoplankton contributed an average of 39, 24 and 37% to euphotic column chl a, respectively. An inverse relationship was observed between the percentages of picoplankton and total chl a. On the other hand, net phytoplankton showed a decreasing trend with increasingly oligotrophic conditions. Of the total mean euphotic column production (0.17 g C m–2 day–1), 37% was attributable to picoplankton, whereas nano and net phytoplankton contributed 40 and 23%, respectively. In contrast to the generally accepted view that picoplankton are low-light adapted, no signs of photoinhibition were observed in surface populations of picoplankton photosynthesizing at high light intensities of ~1500µE m–2 s–1. Below the euphotic zone (100–200m), dark fixation of CO2 was quite significant. The average column dark fixation of CO2 was 0.045g C m–2 day–1 which is ~19% of the euphotic column production. A substantial percentage of dark fixation of CO2 was attributable to organisms in the picoplankton size class. Despite their low sinking rates, picoplankton may be the dominant contributors to organic carbon fluxes to deeper depths through the formation of aggregates with river-derived mineral particles.


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?


This article has been cited by other articles:


Home page
 ScienceHome page
T. L. Richardson and G. A. Jackson
Small Phytoplankton and Carbon Export from the Surface Ocean
Science, February 9, 2007; 315(5813): 838 - 840.
[Abstract] [Full Text] [PDF]


Disclaimer:
Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.