Autor: |
Palijan, Goran, Bogut, Irella, Vidaković, Jasna |
Jazyk: |
angličtina |
Rok vydání: |
2008 |
Předmět: |
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Popis: |
The aim of this investigation was to examine trophic structure of culturable bacterioplankton in relation to repeated inundation-isolation cycles on sampling stations with unequal degree of connection with the river. A change in the ratio of copiotrophs to oligotrophs was expected as the establishment of different carbon sources emerged. The structure of samples was revealed by Principal Component Analysis of abiotic water properties and the chlorophyll-a concentration. Scores of significant components were used in a Multiple Regression as independent variables and the relationship between the scores and abundance of colony forming units was examined. Regression model was significant only for copiotrophs, and their relative dominance was noticed in couple of samples on more isolated sampling stations. In all other samples oligotrophs were a dominant group, especially during the flood pulses or drainage after it. Their elevated abundance was equally distributed in all groups revealed by Principal Component Analysis, and corresponds to the fluvial action. Also concerning the η (eta) squared and R squared values from the two-way ANOVA (stations/samplings) oligotrophs are highly influenced by the sampling period i. e. inundation-isolation cycles. They are probably driven by the allochthonous organic matter provided by floods or have allochthonous origin itself. At the same time, copiotrophs are to some extent coupled with the established water properties, i. e. bottom-up controlled and their abundance is influenced by the sampling stations. These results describe the development of the conditions that promote habitat specific succession of the culturable bacterioplankton. Established differences had disappeared after additional inundation-isolation cycles. |
Databáze: |
OpenAIRE |
Externí odkaz: |
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