Rapid urbanization and economic development in coastal regions have significantly increased coastal nutrient pollution and remarkably changed the phytoplankton community and developed some species into bloom, resulting in large economic losses and serious threats to public health. Therefore, it is indispensable to reveal the shift in the phytoplankton community and phytoplankton abundance, and phytoplankton’s environmental drivers. However, previous studies could not present the details of the environmental drivers of phytoplankton due to samples being collected with low temporal resolution. Here, high-temporal-resolution (daily) samples were collected to investigate the influence of environmental factors on phytoplankton in Qinhuangdao for 44 days. Phytoplankton communities showed a rapid succession, with predominant genera changing in the order Skeletonema–Chaetoceros–Skeletonema–Thalassiosira. Similarly, Thalassiosira pacifica, Skeletonema costatum, Chaetoceros tortissimus, and Chattonella marina were identified as the dominant species and were abundant in 0–1.27 × 10⁷ cells·L⁻¹, 0–9.34 × 10⁶ cells·L⁻¹, 0–6.49 × 10⁶ cells·L⁻¹, and 0–3.64 × 10⁶ cells·L⁻¹, respectively. Moreover, inflows facilitate the rapid succession of the phytoplankton community. Dissolved inorganic phosphorus (DIP) was found to remarkably influence the succession of phytoplankton communities and the bloom of the top three dominant species, i.e., Thalassiosira pacifica, Skeletonema costatum, and Chaetoceros tortissimus. Overall, our results provide high-temporal-resolution observations of phytoplankton community succession and reveal its environmental drivers. This contributes to our current understanding of the occurrence of algae blooms and supports the development of management strategies to control algae bloom in coastal waters.

Phytoplankton blooms have become a global concern due to their negative impacts on public health, aquaculture, tourism, and the economic stability of coastal regions. Therefore, elucidating the shifts in phytoplankton community structure and abundance, as well as their environmental drivers, is crucial. However, existing studies often fail to capture the detailed dynamics of phytoplankton blooms and their environmental triggers due to low temporal observation resolution. In this study, high temporal resolution (daily) samples were collected over 43 days to investigate the influence of environmental factors on phytoplankton in Qinhuangdao in the summer. During the observation period, a total of 45 phytoplankton species were identified, comprising 26 Bacillariophyta species, 16 Dinophyta species, 2 Euglenophyta species, and 1 Chromophyta species. Interestingly, a lag bloom pattern of phytoplankton behind freshwater input was observed across day-to-day samples. Phytoplankton blooms typically lagged 1–3 days behind periods of decreased salinity and nutrient input, suggesting that freshwater influx provides the foundational materials and benefits for these blooms. Moreover, the phytoplankton blooms were triggered by six dominant species, i.e., Chaetoceros spp., Pseudo-nitzschia delicatissima, Skeletonema costatum, Protoperdinium spp., Leptocylindrus minimus, Pseudo-nitzschia pungens, and Thalassiosira spp. Consequently, the succession of phytoplankton showed a predominant genera shift in the following sequence: Nitzschia, Protoperdinium, and Prorocentrum – Skeletonema – Pseudo-nitzschia – Gymnodinium – Leptocylindrus. Besides that, a deterministic process dominated phytoplankton community assembly across time series, and DIP is a key factor in shifting the phytoplankton community structures in this area. In summary, our study offers high-resolution observations on the succession of phytoplankton communities and sheds light on the complex and differentiated responses of phytoplankton to environmental factors. These findings enhance our understanding of the dynamics of phytoplankton blooms and their environmental drivers, which is essential for the effective management and mitigation of their adverse impacts.

Dear Editor'I am writing to kindly request a correction to the funding information in our published paper titled " A lag bloom pattern of phytoplankton after freshwater input events revealed by daily samples during summer in Qinhuangdao coastal water, China".Upon reviewing the this paper, we noticed an error in the funding number listed in the Funding section.Current (incorrect) version:"key R&D Program of Hebei Province, China (Nos. 237301D and 2137302D)"Corrected version:"the key R&D Program of Hebei Province, China (Nos. 23373301D and 21373302D)"The change does not affect the scientific content of the paper, but it is important for accurate funding attribution. Could you please advise how to proceed with this correction?We sincerely apologize for any inconvenience caused and greatly appreciate your assistance. Best regards,

Labyrinthulomycetes protists play important roles in organic matter decomposition and nutrient cycling in marine ecosystems. To better understand their distribution and potential ecological functions in Caofeidian seagrass beds of the Bohai Sea, we conducted high-throughput sequencing of samples collected from multiple habitats, including leaves (L), rhizosphere (R), sediments (S), and seawater (W). Our results revealed distinct habitat-specific patterns of community composition. Oblongichytrium and Stellarchytrium were dominant in certain samples, exhibiting clear differences across stations. Oblongichytrium showed particularly high abundance in leaf and seawater samples, likely reflecting the availability of particulate and dissolved substrates enriched by seagrass beds. In the rhizosphere, Sicyoidochytrium, Stellarchytrium and Labyrinthula were enriched, whereas unclassified Labyrinthulomycetes and Thraustochytriaceae lineages prevailed in seawater and specific leaf samples. Notably, a substantial proportion of sequences corresponded to unclassified lineages, potentially representing uncultured “seagrass-associated” taxa. Compared with previous reports, our study revealed both a significantly higher abundance of Stellarchytrium and a remarkably greater proportion of unclassified lineages, suggesting unique features of Labyrinthulomycetes communities in the Caofeidian seagrass ecosystem. These findings provide new insights into the ecological roles of Labyrinthulomycetes in seagrass beds and offer an important reference for future taxonomic and functional studies of this group.

The symbiotic system of microalgae and fungal microorganisms, such as filamentous fungi, yeasts, and lichen-forming fungi, holds great potential in the fields of environmental remediation and bioresource development. Yet, it faces bottlenecks, including unclear symbiotic mechanisms, high energy consumption for biomass harvesting, poor adaptability to complex wastewater, and insufficient system integration. In this review, we systematically summarized the research progress on microalgae-fungi symbiotic systems in terms of germplasm resource exploration, multifaceted interaction mechanisms, and engineering applications. In particular, we focused on the core advantages of fungal pellet-assisted bioflocculation technology in overcoming the energy bottleneck of biomass harvesting, as well as its optimization strategies. The comprehensive performance of this system in wastewater purification, bioenergy accumulation, and high-value metabolite production was also evaluated. By integrating fundamental mechanisms with engineering application outcomes, we aimed to provide theoretical support and technical guidance for the construction of efficient, stable, and sustainable microalgae-fungi biorefinery platforms. Furthermore, we seek to facilitate the translation of this technology from laboratory research to industrial application.