Aquatic Microbial Ecology | |
Numerical and functional responses of choreo- and oligotrich planktonic ciliates | |
Ingrid Gismervik1  | |
关键词: Ciliates; Growth rates; Feeding rates; Clearance rates; Threshold; Gross growth efficiency; GGE; | |
DOI : 10.3354/ame040163 | |
学科分类:生物科学(综合) | |
来源: Inter-Research | |
【 摘 要 】
ABSTRACT: A total of 6 planktonic naked ciliates were isolated from the Oslofjord, Norway. Numerical and functional responses were investigated using bottle incubations at 11 to 14°C, with the prasinophyceae Nephroselmis pyriformis and cryptophyceae Hemiselmis sp. as food. Growth rates followed hyperbolic curves, which levelled off at about 15000 algal cells ml1 (152 µg C l1). Highest growth rate was recorded for the large heterotroph Strobilidium spiralis (μmax = 1.38 ± 0.08 d1 (mean ± SE). A small mixotroph, Strombidium vestitum, displayed high growth rates (μmax = 1.04 ± 0.05 d1), compared to the larger strombidiids Strombidium conicum, S. acutum and Strombidium sp. (μmax = 0.55 to 0.80 d1). Food thresholds for positive net growth rates were estimated to be in the range of 600 to 3300 algal cells ml1, or 6 to 34 µg C l1. Specific ingestion rates increased at increasing food concentrations, and maximum measured rates were generally in the range of 2 to 4 d1. S. spiralis increased its clearance rate to a maximum of 18.3 ± 0.69 µl h1 as algal concentrations were enhanced from 900 to 2600 algal cells ml1. Gross growth efficiency ranged from 7 to 52% above threshold food levels, with a mean and median of 22 and 23%, respectively.
【 授权许可】
Unknown
【 预 览 】
Files | Size | Format | View |
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RO201911300365921ZK.pdf | 252KB | download |