Pregled bibliografske jedinice broj: 205577
Alternation of factors affecting bacterioplankton abundance in the Danube River floodplain (Kopački Rit, Croatia)
Alternation of factors affecting bacterioplankton abundance in the Danube River floodplain (Kopački Rit, Croatia) // Hydrobiologia, 560 (2006), 1; 405-415 (međunarodna recenzija, članak, znanstveni)
CROSBI ID: 205577 Za ispravke kontaktirajte CROSBI podršku putem web obrasca
Naslov
Alternation of factors affecting bacterioplankton abundance in the Danube River floodplain (Kopački Rit, Croatia)
Autori
Palijan, Goran ; Fuks, Dragica
Izvornik
Hydrobiologia (0018-8158) 560
(2006), 1;
405-415
Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni
Ključne riječi
bacterioplankton abundance; r- and K- strategists; DOC bioavailability; hydrological cycle; limnophase; potamophase
Sažetak
The purpose of this investigation was to determine the influence of different phases of the hydrological cycle on the abundance of colony-forming units (CFU) of bacteria in the Kopački Rit floodplain and to assess temporal and spatial variations in the proportion of eutrophic and oligotrophic bacteria (r- and K-strategists) as a biological indicator of dissolved organic carbon (DOC) availability. Determination of bacterial abundance was performed with abiotic variables (water temperature, depth, Secchi disc transparency, dissolved oxygen, pH, electrical conductivity, ammonia, nitrates+nitrites, total nitrogen and total phosphorus) and one biotic (chl-a) variable, and dimensionality reduced with principal component analysis (PCA). The component scores were used as independent variables in a multiple regression and the relationship between scores (indirect variables) and bacterial abundance was examined. An elevated bacterial abundance was observed during the limnophase (floodplain isolated from the river) and potamophase (flood). During the limnophase also the highest chl-a concentrations were found and in Sakadaš Lake during September 2003 significantly higher numbers of eutrophic than oligotrophic bacteria emerged (P=0.026). During potamophase the opposite state was established. Elevated bacterial abundance occurred in parallel with minimal chl-a concentrations and during July 2004 in the Čonakut Channel a significantly higher number of oligotrophic than eutrophic bacteria emerged (P<0.001). Differentiation in the number of eutrophic and oligotrophic bacteria suggests the existence of a higher concentration of labile DOC during September 2003 than during July 2004. Multiple regression analysis explains 13.6% of the variation in abundance of eutrophic bacteria. The regression model for oligotrophic bacteria is not significant. The results suggest two different mechanisms control bacterioplankton numbers to some extent in the Kopački Rit floodplain. In addition, two sources of DOC differentiating the quality of organic matter predominate under totally different hydrological regimes. Under these conditions, eutrophic bacteria may be partially bottom-up controlled, whereas it is not clear how the abundance of oligotrophs is controlled.
Izvorni jezik
Engleski
Znanstvena područja
Biologija
POVEZANOST RADA
Projekti:
0122009
MZOS-0098111 - Mehanizam dugoročnih promjena u ekosustavu Jadranskog mora (Degobbis, Danilo, MZOS ) ( CroRIS)
Ustanove:
Filozofski fakultet, Osijek
Citiraj ovu publikaciju:
Časopis indeksira:
- Current Contents Connect (CCC)
- Web of Science Core Collection (WoSCC)
- Science Citation Index Expanded (SCI-EXP)
- SCI-EXP, SSCI i/ili A&HCI
- Scopus