Basin-scale variation in planktonic ciliate distribution: A detailed temporal and spatial study of the Yellow Sea

Abstract

Monthly variations in the distribution of planktonic ciliates were studied over eight months (2006–2007) in the Yellow Sea, a temperate marginal sea of economic and ecological importance. We simultaneously assess ciliates at three levels: seasonal cycle, basin-scale water masses, and frontal systems. Ciliates exhibited a seasonal cycle, with two peaks of abundance (May and August) but only one biomass peak (May); larger ciliates were more prevalent in spring, while smaller ones dominated in the summer. Abundance and biomass were associated with different water masses, which then influenced the entire seasonal pattern in the basin. High ciliate abundance mainly occurred around a thermal front from December to April and occurred at a tidal front in August through October. This study clearly indicates that water masses and frontal systems are key areas to examine; consequently, we argue that if ciliates are to be included in food web dynamics (and associated basin-scale models), we must assess their spatio-temporal variation on regional scales (water masses, fronts). Our case study provides a framework for future work in this direction.

Key words:

• Abundance
• biomass
• ciliate
• seasonal cycle
• water masses
• Yellow Sea

Acknowledgements

We thank the crew of R/V Beidou and Science 3 for their help and cooperation.

Funding

This study was financially supported by special funds from the National Key Basic Research Program of PR China [No. 2011CB409804]; Natural Science Foundation of China [NSFC No. 41121064], [40876085].

Editorial responsibility: David Montagnes

Additional information

Funding

Funding: This study was financially supported by special funds from the National Key Basic Research Program of PR China [No. 2011CB409804]; Natural Science Foundation of China [NSFC No. 41121064], [40876085].