|
|
|
|
|
Jaeschke, Andrea; Ziegler, Martin; Hopmans, Ellen C.; Reichart, Gert-jan; Lourens, Lucas J.; Schouten, Stefan; Damste, Jaap S. Sinninghe. |
Anaerobic ammonium oxidation (anammox) has been recognized as an important process converting fixed nitrogen to N(2) in many marine environments, thereby having a major impact on the present-day marine nitrogen cycle. However, essentially nothing is known about the importance of anammox in past marine nitrogen cycles. In this study, we analyzed the distribution of fossil ladderane lipids, derived from bacteria performing anammox, in a sediment core from the northern Arabian Sea. Concentrations of ladderane lipids varied between 0.3 and 5.3 ng g(-1) sediment during the past 140 ka, with high values observed during the Holocene, intervals during the last glacial, and during the penultimate interglacial. Maxima in ladderane lipid abundances correlate with... |
Tipo: Text |
|
Ano: 2009 |
URL: https://archimer.ifremer.fr/doc/00218/32942/31436.pdf |
| |
|
|
Byrne, Nathalie; Strous, Marc; Crepeau, Valentin; Kartal, Boran; Birrien, Jean-louis; Schmid, Markus; Lesongeur, Francoise; Schouten, Stefan; Jaeschke, Andrea; Jetten, Mike; Prieur, Daniel; Godfroy, Anne. |
Recent studies indicate that ammonia is an important electron donor for the oxidation of fixed nitrogen, both in the marine water column and sediments. This process, known as anammox, has so far only been observed in a large range of temperature habitats. The present study investigated the role of anammox in hydrothermal settings. During three oceanographic expeditions to the Mid-Atlantic Ridge, hydrothermal samples were collected from five vent sites, at depths ranging from 750 to 3650m from cold to hot habitats. Evidence for the occurrence of anammox in these particular habitats was demonstrated by concurrent surveys, including the amplification of 16S rRNA gene sequences related to known anammox bacteria, ladderanes lipids analysis and measurement of a... |
Tipo: Text |
Palavras-chave: Hydrothermal vent; Ladderanes; 16S rRNA; Activity; Micro organisms; Anammox. |
Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-6921.pdf |
| |
|
|
|