Role of bacteria in marine barite precipitation: a case study using Mediterranean seawater.
Sci Total Environ
; 512-513: 562-571, 2015 Apr 15.
Article
in En
| MEDLINE
| ID: mdl-25647371
ABSTRACT
Marine bacteria isolated from natural seawater were used to test their capacity to promote barite precipitation under laboratory conditions. Seawater samples were collected in the western and eastern Mediterranean at 250 m and 200 m depths, respectively, since marine barite formation is thought to occur in the upper water column. The results indicate that Pseudoalteromonas sp., Idiomarina sp. and Alteromonas sp. actually precipitate barite under experimental conditions. Barite precipitates show typical characteristics of microbial precipitation in terms of size, morphology and composition. Initially, a P-rich phase precipitates and subsequently evolves to barite crystals with low P contents. Under laboratory conditions barite formation correlates with extracellular polymeric substances (EPS) production. Barite precipitates are particularly abundant in cultures where EPS production is similarly abundant. Our results further support the idea that bacteria may provide appropriate microenvironments for mineral precipitation in the water column. Therefore, bacterial production in the past ocean should be considered when using Ba proxies for paleoproductivity reconstructions.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Seawater
/
Bacteria
/
Barium Sulfate
/
Water Pollutants, Chemical
Language:
En
Journal:
Sci Total Environ
Year:
2015
Document type:
Article