Naslov
Distribution of cryptophytes along trophic gradients in the Adriatic Sea.

Autori
Viličić, Damir ; Ivančić, Ingrid ; Carić, Marina ; Ahel, Marijan ; Terzić, Senka

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Proceedings of South-eastern Europe Programme Symposium "Ecosystem dynamics, marine chemistry, aquaculture and management in the Adriatic and north Norwegian coastal zone" / Wassmann, Paul ; Ćosović, Božena - Zagreb : Norwegian Research Council, 2005, 29-31

Skup
South-eastern Europe Programme Symposium Ecosystem dynamics, marine chemistry, aquaculture and management in the Adriatic and north Norwegian coastal zone

Mjesto i datum
Hvar, Hrvatska, 27.04.2005. - 01.05.2005

Vrsta sudjelovanja
Pozvano predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
cryptophytes; distribution; trophic; gradient; Adriatic Sea

Sažetak
Among marine and brackish nanoplankton Cryptophytes are common, unicellular, flagellated protists. Cells are easily recognizable under the light microscope (much better by phase contrast than by fluorescent microscope), due to their stiff proteinaceous periplast. We try to define distribution of cryptophytes along two trophic gradients. The first one is in the northern Adriatic (Istrian profile), where the river Po and northwesterly inflowing, oligotrophic current influences could be traced. The second profile is along the Velebit Channel and Zrmanja Estuary. Abundant cryptophytes were found in brackish and marine environments ; thus cryptophyte distribution was weakly correlated with salinity. Cryptophyte abundances provided positive correlation with alloxanthin concentrations. Maximum cryptophyte abundances in the N Adriatic and in the Zrmanja Estuary appear in late spring and summer, together with dinoflagellates. These two components appear in the environment enriched with dissolved organic matter produced by the spring diatom blooms. Most phytoplankton are able to use organic substances for growth (mixotrophy). Cryptophytes can phagotrophicaly graze bacteria. In addition cells can obtain organic substances directly from the solution through the process of osmotrophy. On the other hand, cryptophytes are important prey organisms for ciliates. Ingestion of cryptophytes by dinoflagellates was also detected in the environment of limited phosphorus. In the Adriatic, the abundance of cryptophytes was positively and significantly correlated with abundance of dinoflagellates, indicating their metabolic mutualism. This is an important ecological aspect in the coexistance of many of species in the oligotrophic environment. We investigated the interrelationship between cryptophyte bundance/biomass, abiotic and biotic factors. The case study along the Istrian profile in July 2004 is presented.

Izvorni jezik
Engleski

Znanstvena područja
Geologija, Biologija

POVEZANOST RADA