Тип публикации: статья из журнала
Год издания: 2003
Идентификатор DOI: 10.1046/j.1365-2427.2003.01009.x
Ключевые слова: cyanobacteria; daphnids; diatoms; fatty acids
Аннотация: 1. We studied the composition of fatty acids (FAs) in the seston from two small freshwater reservoirs (Bugach and Lesnoi) with distinct periodicity of domination by cyanobacteria and eukaryotic algae during the growth season. 2. The diatoms in the both reservoirs were characterised by a high content of 14:0 and C16 unsaturated acidПоказать полностьюs, whereas that of the essential FA 20:5omega3 [eicosapentanoic acid (EPA)] was low. The correlation between this polyunsaturated FA (PUFA) and diatom biomass was not significant in either reservoir. The percentage of 20:5omega3 in seston significantly correlated with the biomass of euglenophyta in Bugach and dinophyta in Lesnoi. Hence the diatoms, usually referred as a valuable food for zooplankton, were not an important source of the essential PUFA in these systems. 3. The dominant cyanobacteria in Bugach, and the green algae in Lesnoi, both contained the same marker acids: 18:3omega3 and 18:2omega6. Hence, a discrimination between these two phytoplanktonic groups on the basis of FA biomarkers may be difficult in some cases. 4. We found no significant correlation between the content of 20:5omega3 in seston and the biomass of the dominant daphniids in either reservoir. This is contrary to expectations, based on the literature, that EPA is generally important. Rather, the biomass of the two dominant Daphnia species in Bugach correlated strongly with the content of 18:3omega3 in the seston. The cyanobacteria were a probable source of this omega3 FA for Daphnia . We conclude that EPA is not always important for Daphnia populations although, in such cases, some other PUFA (e.g. 18:3omega3) might be related to their growth.
Журнал: FRESHWATER BIOLOGY
Выпуск журнала: Vol. 48, Is. 3
Номера страниц: 394-403
ISSN журнала: 00465070
Место издания: OXFORD
Издатель: BLACKWELL PUBLISHING LTD