Aloricate ciliates and tintinnids had different vertical distributions: higher aloricate ciliate abundance in waters 30–70 m above the bottom, higher tintinnid abundance near bottom.
The proportion of tintinnids among the total ciliate abundance decreased with distance from the bottom.
The Changjiang River discharge in summer enhanced aloricate ciliate abundance compared with spring and autumn, although tintinnid abundance did not change significantly.