Data from: Distribution Patterns and Driving Mechanisms of Ciliate Communities in the Northeastern South China Sea

Ciliates are common components of the microplankton and play crucial roles in marine microbial food web, yet few studies have attempted to explore their comprehensive biogeographical information in the South China Sea and little is known regarding how community assembly and species association vary with habitat and depth. An extensive survey of ciliate diversity was conducted based on morphological identification in the northeastern South China Sea (NESCS) during the winter of 2013, and the spatial distribution, driving mechanisms, and network relationships of ciliate community were revealed. Our results showed that ciliate community compositions were relatively similar between nearshore and offshore areas but significantly different between upper and deep water. Higher ciliate abundances were found in nearshore and upper water than offshore and deep water, primarily due to differences in light, nutrients, and food resources. Across the entire sea area, environmental factors had a more significant influence on communities than spatial factors, suggesting that deterministic processes played a significant role in ciliate distribution. Co-occurrence network analysis revealed that ciliate networks were more stable in offshore and upper waters than in nearshore and deep waters, which was probably related to more complex relationships in two former waters. Combined with the broader niche breadth, our study suggested that the ciliate community in offshore and upper waters would show stronger defense capability to environmental changes. This study provides the first comprehensive overview of ciliate distribution and determinant in the NESCS, offering a scientific basis for exploring the environmental adaptability of planktonic communities in tropical marine areas.