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Ciliate dynamics in response to changing biotic and abiotic conditions in a large, deep lake (Lake Constance)
| Content Provider | Semantic Scholar |
|---|---|
| Author | Gaedke, Ursula Wickham, Stephen A. |
| Copyright Year | 2004 |
| Abstract | From 1987 to 1998, ciliates and their prey and predator communities in Lake Constance (which is large, deep and meso-eutrophic) were intensively studied as the lake underwent re- oligotrophication. Ciliate biomass exhibited the bimodal seasonal distribution typical for meso- eutrophic lakes, with high biomass in spring and summer and low biomass in winter and during the clear-water phase. Cluster analysis produced 9 groups of temporally co-occurring ciliate morphotypes with potentially similar ecological characteristics. The clusters exhibited a larger seasonality than found in the size distribution, showing that size alone failed to capture some ciliate seasonal dynamics. Ciliate biomass declined by approx. 30% during the 12 yr of study, i.e. considerably less than daphnids (and total phosphorus). This yielded a significant increase in the ratio between summer ciliate and daphnid biomass as re-oligotrophication progressed, in contrast to previous studies. Few indications for a mechanistic link between phosphorus concentrations (which declined 3-fold during the study period) and ciliate biomass or community composition via group-specific food concentrations were found. The relative contribution of 3 of the 9 clusters changed as re-oligotrophication progressed. Ciliate size distribution was related to re-oligotrophication and daphnid biomass in summer. The smallest and largest ciliates gained importance when daphnids decreased, whereas the biomass of large ciliates declined. Generally, summer daphnid biomass had a greater predictive power for attributes of the ciliate community than the other factors studied (phosphorus, prey biomass, copepod biomass). The extent of bottom-up and top-down control of ciliates appeared to be time- and group- specific. Overall, the ciliate community exhibited remarkably recurrent seasonal patterns, despite major alternations in abiotic and biotic conditions. |
| Starting Page | 247 |
| Ending Page | 261 |
| Page Count | 15 |
| File Format | PDF HTM / HTML |
| DOI | 10.3354/ame034247 |
| Volume Number | 34 |
| Alternate Webpage(s) | https://www.int-res.com/articles/ame2004/34/a034p247.pdf |
| Alternate Webpage(s) | https://doi.org/10.3354/ame034247 |
| Language | English |
| Access Restriction | Open |
| Content Type | Text |
| Resource Type | Article |
