Data/hora: 06/06/2024 05:36:33

Provedor de dados: 	5	
País: 	France	
Título: 	Phased oscillations in cell numbers and nitrate in batch cultures of Alexandrium tamarense (Dinophyceae)	
Autores: 	Collos, Yves; Hadjadji, Imene; Plisson, Benoit; Cecchi, Philippe; Laabir, Mohamed; Bechemin, Christian; Masseret, Estelle.	
Data: 	2011-10	
Ano: 	2011	
Palavras-chave: 	Alexandrium tamarense; Archaea; Bacteria; Decay; Growth; Nitrate; Nitrification; Oscillations.	
Resumo: 	Alexandrium tamarense (M. Lebour) Balech strains isolated in spring 2007 from a single bloom in Thau lagoon have been grown in nonaxenic artificial media. For three strains showing large oscillations in biomass (crashes followed by recoveries) on a scale of several days, a significant relationship was observed between changes in cell densities (as in vivo fluorescence) and changes in nitrate concentrations. Increases in cell densities were accompanied by decreases in nitrate, while decreases in cell densities corresponded to increases in nitrate, presumably due to nitrification. Net increases in nitrate could reach up to 15 mu mol N . L(-1) . d(-1) indicating a very active nitrifying archaeal/bacterial population. However, following population crashes, algal cells can recover and attain biomass levels similar to those reached during the first growth phase. This finding indicates that those archaea/bacteria do not compete for nutrients or do not hamper algal growth under those conditions. In contrast to diatoms, dinoflagellates such as A. tamarense do not excrete/exude dissolved organic matter, thus preventing excessive bacterial growth. This mechanism could help explain the recovery of this species in the presence of bacteria.	
Tipo: 	Text	
Idioma: 	Inglês	
Identificador: 	http://archimer.ifremer.fr/doc/00049/16046/13585.pdf

DOI:10.1111/j.1529-8817.2011.01031.x	
Editor: 	Wiley-blackwell	
Relação: 	http://archimer.ifremer.fr/doc/00049/16046/	
Formato: 	application/pdf	
Fonte: 	Journal Of Phycology (0022-3646) (Wiley-blackwell), 2011-10 , Vol. 47 , N. 5 , P. 1057-1062	
Fonte: 	2011 Phycological Society of America