Dependency of dinoflagellate vertical migration on salinity stratification
| Autor: | Therese Jephson, Per Carlsson, Tony Fagerberg |
|---|---|
| Rok vydání: | 2011 |
| Předmět: | |
| Zdroj: | Aquatic Microbial Ecology. 63:255-264 |
| ISSN: | 1616-1564 0948-3055 |
| DOI: | 10.3354/ame01498 |
| Popis: | Increasing precipitation and surface water temperature due to global change may strengthen the salinity gradient in coastal regions, which could influence the behaviour of dinoflagel- late migration. We studied diel vertical migration (DVM) behaviour in the dinoflagellates Prorocen- trum minimum and Heterocapsa triquetra using vertically stratified laboratory columns with 3 differ- ent salinity gradients (difference of 6, 11 and 16 psu). With nutrient-depleted conditions at the surface, and with nutrients added below the halocline, P. minimum remained mainly concentrated in the bottom water, while H. triquetra performed DVM under all 3 salinity treatments. H. triquetra migrated through a salinity difference of 6 and 11 psu, concentrated at the surface at noon, then migrated to the nutrient-rich bottom water during the night. A salinity gradient of 16, however, stopped H. triquetra cells from moving through the gradient and resulted in a concentration of cells in the cline during the night. At midday, cells were again found at the surface. P. minimum and H. tri- quetra grown in 4 different salinities (10, 15, 20, 26 psu) and at 3 different temperatures (10, 15, 20°C) showed higher specific growth rates with increasing temperature only in the 2 highest salinity treat- ments. At 10°C, specific growth rates were not affected by different salinities. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|