TY - JOUR
T1 - Dinitrogen-fixing cyanobacteria in microbial mats of two shallow coral reef ecosystems
AU - Charpy, Loic
AU - Palinska, Katarzyna A.
AU - Casareto, Beatriz
AU - Langlade, Marie José
AU - Suzuki, Yoshimi
AU - Abed, Raeid M.M.
AU - Golubic, Stjepko
N1 - Funding Information:
This work was supported by grants from the Ocean Development Sub-Committee of France–Japan S&T Cooperation, Mitsubishi cooperation, the Ministry of Education, Science, Sport, and Culture of Japan and from IRD. Hanse Wissenschaftskolleg, Delmenhorst and Alexander-von-Humboldt Foundation, Bad Godesberg, Germany supported collaborative research on cyanobacterial diversity. We thank A. Couté for his help in Sesoko cyanobacteria identification, the laboratory ECOMAR from the University of La Reunion, and the Sesoko Marine Station for their help in the field. We wish also to thank Tatjana Schwetzler for the help in molecular analysis.
PY - 2010/1
Y1 - 2010/1
N2 - Dinitrogen-fixing organisms in cyanobacterial mats were studied in two shallow coral reef ecosystems: La Reunion Island, southwestern Indian Ocean, Sesoko (Okinawa) Island, and northwestern Pacific Ocean. Rapidly expanding benthic miniblooms, frequently dominated by a single cyanobacterial taxon, were identified by microscopy and molecular tools. In addition, nitrogenase activity by these blooms was measured in situ. Dinitrogen fixation and its contribution to mat primary production were calculated using 15N2 and 13C methods. Dinitrogen-fixing cyanobacteria from mats in La Reunion and Sesoko showed few differences in taxonomic composition. Anabaena sp. among heterocystous and Hydrocoleum majus and Symploca hydnoides among nonheterocystous cyanobacteria occurred in microbial mats of both sites. Oscillatoria bonnemaisonii and Leptolyngbya spp. occurred only in La Reunion, whereas Hydrocoleum coccineum dominated in Sesoko. Other mats dominated by Hydrocoleum lyngbyaceum, Phormidium laysanense, and Trichocoleus tenerrimus occurred at lower frequencies. The 24-h nitrogenase activity, as measured by acetylene reduction, varied between 11 and 324 nmoles C2H2 reduced μg-1 Chl a. The highest values were achieved by heterocystous Anabaena sp. performed mostly during the day. Highest values for nonheterocystous cyanobacteria were achieved by H. coccineum mostly during the night. Daily nitrogen fixation varied from nine (Leptolyngbya) to 238 nmoles N2 μg-1 Chl day-1 (H. coccineum). Primary production rates ranged from 1,321 (S. hydnoides) to 9,933 nmoles C μg-1 Chl day-1 (H. coccineum). Dinitrogen fixation satisfied between 5% and 21% of the nitrogen required for primary production.
AB - Dinitrogen-fixing organisms in cyanobacterial mats were studied in two shallow coral reef ecosystems: La Reunion Island, southwestern Indian Ocean, Sesoko (Okinawa) Island, and northwestern Pacific Ocean. Rapidly expanding benthic miniblooms, frequently dominated by a single cyanobacterial taxon, were identified by microscopy and molecular tools. In addition, nitrogenase activity by these blooms was measured in situ. Dinitrogen fixation and its contribution to mat primary production were calculated using 15N2 and 13C methods. Dinitrogen-fixing cyanobacteria from mats in La Reunion and Sesoko showed few differences in taxonomic composition. Anabaena sp. among heterocystous and Hydrocoleum majus and Symploca hydnoides among nonheterocystous cyanobacteria occurred in microbial mats of both sites. Oscillatoria bonnemaisonii and Leptolyngbya spp. occurred only in La Reunion, whereas Hydrocoleum coccineum dominated in Sesoko. Other mats dominated by Hydrocoleum lyngbyaceum, Phormidium laysanense, and Trichocoleus tenerrimus occurred at lower frequencies. The 24-h nitrogenase activity, as measured by acetylene reduction, varied between 11 and 324 nmoles C2H2 reduced μg-1 Chl a. The highest values were achieved by heterocystous Anabaena sp. performed mostly during the day. Highest values for nonheterocystous cyanobacteria were achieved by H. coccineum mostly during the night. Daily nitrogen fixation varied from nine (Leptolyngbya) to 238 nmoles N2 μg-1 Chl day-1 (H. coccineum). Primary production rates ranged from 1,321 (S. hydnoides) to 9,933 nmoles C μg-1 Chl day-1 (H. coccineum). Dinitrogen fixation satisfied between 5% and 21% of the nitrogen required for primary production.
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U2 - 10.1007/s00248-009-9576-y
DO - 10.1007/s00248-009-9576-y
M3 - Article
C2 - 19705191
AN - SCOPUS:74149092105
SN - 0095-3628
VL - 59
SP - 174
EP - 186
JO - Microbial Ecology
JF - Microbial Ecology
IS - 1
ER -