Freshwater salinization, which can be caused by saltwater intrusion, urbanization, and climate change, is becoming an extensive global environmental problem. Microeukaryotic plankton are key components of aquatic ecosystems and play significant ecological roles. However, few studies have investigated the influences of small salinity shifts on microeukaryotic plankton community assembly and co-occurrence networks in inland freshwaters. In a recent study, researchers used high-throughput sequencing to analyze microeukaryotic plankton communities in a subtropical urban reservoir. They found that increasing salinity altered the community composition and led to a significant decrease in plankton diversity. The salinity changes influenced the microeukaryotic plankton community assembly primarily by regulating the deterministic-stochastic balance. The core plankton sub-network had greater robustness at low salinity levels, while the satellite sub-networks had greater robustness at medium/high salinity levels. Although longer-term studies are needed, these results suggest that salinity is an important driving force shaping microeukaryotic plankton community dynamics and provide new insights into the plankton ecology of inland urban waters.