Scheda di dettaglio – i prodotti della ricerca

DatoValore
TitleSusceptibility of bacterioplankton to nutrient enrichment of oligotrophic and ultraoligotrophic lake waters
AbstractWe carried out laboratory experiments in one ultraoligotrophic pristine Andean lake (Lake Gutiérrez, Argentina) and in one subalpine lake that is now at the edge of the oligo- to mesotrophic condition (Lake Maggiore, Italy). Lake water was amended with phosphorus (+P), organic carbon (+C), alone or in combination (+CP), to test for short-term changes (48 hours) in bacteria activity and community structure (CARD FISH). Experiments were carried out in spring and summer. Results showed that bacterial production increased in the +CP treatment in both lakes, and in the +P treatment in the ultroligotrophic lake. In both lakes the bacterial activity increased more rapidly in summer (within 24 hours). Bacteria composition changed in both seasons in all the treatments. At the beginning of the experiments the subclass of ²-Proteobacteria dominated both lakes, while ³-Proteobacteria showed higher percentage in spring in Lake Maggiore and in summer in Lake Gutiérrez. After incubation, in spring and in particular in the +CP treatment, we observed an increase in the relative importance of ³-Proteobacteria in both lakes, whereas in Lake Maggiore this group declined in the summer experiments following an increase in ²-Proteobacteria. All our results indicate the different response of bacterioplankton in systems at the edges of the oligotrophic range.
SourceJournal of limnology (Testo stamp.) 67(2), pp. 120–127
Keywordsbacterioplanktonultraoligotrophic lakephosphorus additioncarbon additionoligotrophic lake
JournalJournal of limnology (Testo stamp.)
EditorIstituto per lo Studio degli Ecosistemi., Verbania Pallanza, Italia
Year2008
TypeArticolo in rivista
AuthorsBertoni R., Callieri C., Balseiro E.(1), Modenutti B.(1)
Text53038 2008 bacterioplankton ultraoligotrophic lake phosphorus addition carbon addition oligotrophic lake Susceptibility of bacterioplankton to nutrient enrichment of oligotrophic and ultraoligotrophic lake waters Bertoni R., Callieri C., Balseiro E. 1 , Modenutti B. 1 1 CONICET UNC Lab. Limnol., Universidad Nacional del Comahue, Bariloche Argentina We carried out laboratory experiments in one ultraoligotrophic pristine Andean lake Lake Gutierrez, Argentina and in one subalpine lake that is now at the edge of the oligo to mesotrophic condition Lake Maggiore, Italy . Lake water was amended with phosphorus P , organic carbon C , alone or in combination CP , to test for short term changes 48 hours in bacteria activity and community structure CARD FISH . Experiments were carried out in spring and summer. Results showed that bacterial production increased in the CP treatment in both lakes, and in the P treatment in the ultroligotrophic lake. In both lakes the bacterial activity increased more rapidly in summer within 24 hours . Bacteria composition changed in both seasons in all the treatments. At the beginning of the experiments the subclass of ² Proteobacteria dominated both lakes, while ³ Proteobacteria showed higher percentage in spring in Lake Maggiore and in summer in Lake Gutierrez. After incubation, in spring and in particular in the CP treatment, we observed an increase in the relative importance of ³ Proteobacteria in both lakes, whereas in Lake Maggiore this group declined in the summer experiments following an increase in ² Proteobacteria. All our results indicate the different response of bacterioplankton in systems at the edges of the oligotrophic range. 67 2 Published version Articolo in rivista Istituto per lo Studio degli Ecosistemi. 1129 5767 Journal of limnology Testo stamp. Journal of limnology Testo stamp. J. limnol. Testo stamp. Journal of limnology. Testo stamp. roberto.bertoni BERTONI ROBERTO cristiana.callieri CALLIERI CRISTIANA TA.P04.016.004 Ecologia teorica e applicata degli ecosistemi acquatici