Unicellular cyanobacterial distributions broaden the oceanic N2 fixation domain.
Science
; 327(5972): 1512-4, 2010 Mar 19.
Article
em En
| MEDLINE
| ID: mdl-20185682
ABSTRACT
Nitrogen (N2)-fixing microorganisms (diazotrophs) are an important source of biologically available fixed N in terrestrial and aquatic ecosystems and control the productivity of oligotrophic ocean ecosystems. We found that two major groups of unicellular N2-fixing cyanobacteria (UCYN) have distinct spatial distributions that differ from those of Trichodesmium, the N2-fixing cyanobacterium previously considered to be the most important contributor to open-ocean N2 fixation. The distributions and activity of the two UCYN groups were separated as a function of depth, temperature, and water column density structure along an 8000-kilometer transect in the South Pacific Ocean. UCYN group A can be found at high abundances at substantially higher latitudes and deeper in subsurface ocean waters than Trichodesmium. These findings have implications for the geographic extent and magnitude of basin-scale oceanic N2 fixation rates.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Água do Mar
/
Cianobactérias
/
Ecossistema
/
Fixação de Nitrogênio
Idioma:
En
Ano de publicação:
2010
Tipo de documento:
Article