Scheda di dettaglio – i prodotti della ricerca
| Dato | Valore |
|---|---|
| Title | Bacterial grazing by mixotrophic flagellates and Daphnia longispina: a comparison in a fishless alpine lake |
| Abstract | We compared the bacterivory of Mixotrophic Flagellates (MxFl) and of Daphnia longispina in a fishless high altitude lake with a simple food web. Field experiments were carried out during the ice-free period in Lago Paione Superiore (LPS, Italian Central Alps) in order to measure species-specific direct uptake of fluorescently labelled bacteria (FLB) by MxFl and Daphnia. Bacterial production of DNA and protein were measured as well as Dissolved Organic Carbon (DOC). Between ice melt and September Gymnodinium spp., Dinobryon sertularia, Chromulina spp. and Ochromonas sp. represented the most common groups of MxFl in the lake. On average they ingested 2.9, 3.7, 9.3 and 14.6 bacteria ind-1 h-1 respectively, whereas Daphnia ingested 1.9 bacteria 10^6 ind-1 h-1. However, the MxFl community ingestion rate was always higher than the rate of Daphnia except in mid August when the Daphnia population ingested 2.4 times more bacteria than MxFl. MxFl and Daphnia grazing did not show any significant correlation with bacterial abundance and biomass (ro Spearman, P > 0.05) but a significant correlation was found between MxFl grazing and Thy uptake at 9 m (ro Spearman = 0.821, P < 0.014, xy pairs = 7). From this study it appears that Daphnia actively feeds on bacteria when it first appears in the lake, but overall, the Daphnia population had a lower impact on bacteria than did mixotrophic flagellates. |
| Source | Aquatic microbial ecology 42, pp. 127–137 |
| Keywords | mixotrophic flagellates grazingDaphnia longispina grazingFLBbacterial productionLago Paione Superiore |
| Journal | Aquatic microbial ecology |
| Editor | Inter-Research., Oldendorf/Luhe, Germania |
| Year | 2006 |
| Type | Articolo in rivista |
| Authors | Callieri C., Corno G., Bertoni R. |
| Text | 52912 2006 mixotrophic flagellates grazing Daphnia longispina grazing FLB bacterial production Lago Paione Superiore Bacterial grazing by mixotrophic flagellates and Daphnia longispina a comparison in a fishless alpine lake Callieri C., Corno G., Bertoni R. CNR Istituto per lo Studio degli Ecosistemi, Verbania We compared the bacterivory of Mixotrophic Flagellates MxFl and of Daphnia longispina in a fishless high altitude lake with a simple food web. Field experiments were carried out during the ice free period in Lago Paione Superiore LPS, Italian Central Alps in order to measure species specific direct uptake of fluorescently labelled bacteria FLB by MxFl and Daphnia. Bacterial production of DNA and protein were measured as well as Dissolved Organic Carbon DOC . Between ice melt and September Gymnodinium spp., Dinobryon sertularia, Chromulina spp. and Ochromonas sp. represented the most common groups of MxFl in the lake. On average they ingested 2.9, 3.7, 9.3 and 14.6 bacteria ind 1 h 1 respectively, whereas Daphnia ingested 1.9 bacteria 10 6 ind 1 h 1. However, the MxFl community ingestion rate was always higher than the rate of Daphnia except in mid August when the Daphnia population ingested 2.4 times more bacteria than MxFl. MxFl and Daphnia grazing did not show any significant correlation with bacterial abundance and biomass ro Spearman, P > 0.05 but a significant correlation was found between MxFl grazing and Thy uptake at 9 m ro Spearman = 0.821, P < 0.014, xy pairs = 7 . From this study it appears that Daphnia actively feeds on bacteria when it first appears in the lake, but overall, the Daphnia population had a lower impact on bacteria than did mixotrophic flagellates. 42 Published version Articolo pubblicato 11_Callieri_et_al_2006_AME.pdf Articolo in rivista Inter Research. 0948 3055 Aquatic microbial ecology Aquatic microbial ecology Aquat. microb. ecol. Aquatic microbial ecology. AME. Aquatic microbial ecology Aquatic microbial ecology Print AME Oldenburg gianluca.corno CORNO GIANLUCA roberto.bertoni BERTONI ROBERTO cristiana.callieri CALLIERI CRISTIANA TA.P02.014.002 Impatto dei cambiamenti globali sugli ecosistemi acquatici |