A dataset on spatiotemporal variation of phytoplankton communities in the mangrove wetland of Shenzhen Bay.

The Futian Mangrove Ecological Park (FMEP), a vital subtropical conservation area within Shenzhen Bay, encompasses freshwater lakes and saltwater mangrove wetlands, which have been significantly impacted by human activities over recent decades. Phytoplankton, a key element of the mangrove ecosystem, has experienced over 30 occurrences of harmful algal blooms (HABs) in the coastal waters of Shenzhen Bay since the 1980s. This study presents an extensive dataset documenting the spatiotemporal variation in phytoplankton communities and associated physicochemical parameters within the FMEP. Over a 3-year period from January 2019 to October 2021, 60 water samples were collected at five distinct stations during seasonal surveys, capturing the salinity gradient. Both spatial and temporal variability of phytoplankton community and environmental factors are strongly reflected in our data. Since the dataset was generated using microscopy-based method, it offers precious opportunities for ecological analyses and serves as a valuable reference for biodiversity in future studies, especially in the context of anthropogenic impacts and climate change.