Zhang Yanrong, Yin Zengqiang, Du Yinghai, Wei Xiangxu, Lan Yikai, Yu Quan, Wang Yan, Tian Tao, Chen Lei, Yang Jun
College of Marine Science and Environment, Dalian Ocean University, Dalian 116023, China.
College of Fisheries and Life Science, Dalian Ocean University, Dalian 116023, China.
Biology (Basel). 2025 May 21;14(5):578. doi: 10.3390/biology14050578.
Phytoplankton serve as crucial producers in marine ecosystems, and their community composition and populations' dispersion directly or indirectly influence the productivity of marine waters via the trophic cascade effect within the food chain. A survey was undertaken in September 2021 and March, April, and November 2022 to examine the phytoplankton structure and the environmental variables influencing ecological niche differentiation in the waters of Tahe Bay in Lushun, Dalian city, China. The findings indicated that there are 83 species representing forty-one genera and six phyla, with an annual mean abundance of 22.13 × 10 ind·m, predominantly represented by Bacillariophyta (65 species, constituting 78.31% of the total species). The phytoplankton richness indices varied from 0.83 to 4.99, diversity indices ranged from 2.03 to 2.80, and evenness indices spanned from 0.28 to 0.84. Pearson's correlation between phytoplankton abundance and community diversity with environmental parameters, including water temperature, salinity, pH, DO, NH-N, and NO-N, was substantial in Tahe Bay's waters. The dominant species, comprising 20 species across three phyla, primarily include broad-niche species, with being the most prevalent species, except during summer. The extent of ecological niche overlap among the dominant species varied by season, exhibiting 40.0% severe overlap in September 2021, 100.0% severe overlap in March 2022, 93.0% severe overlap in April 2022, and 58.0% severe overlap in November 2022. The findings of redundancy analysis (RDA) and canonical correspondence analysis (CCA) revealed that COD, water temperature, NO-N, DIP, NO-N, and NH-N are the primary environmental variables influencing the ecological niche differentiation of dominant species of phytoplankton. The results of the study elucidate the alteration rules of dominant species and the stability of the community structure of the phytoplankton community in this sea area, thereby offering a theoretical foundation for the scientific assessment of the ecological health of the area and the sustainable utilization of marine biological resources.
浮游植物是海洋生态系统中的关键生产者，其群落组成和种群分布通过食物链中的营养级联效应直接或间接地影响海水的生产力。于2021年9月以及2022年3月、4月和11月进行了一项调查，以研究大连旅顺塔河湾水域的浮游植物结构以及影响生态位分化的环境变量。研究结果表明，共有83个物种，分属于41个属和6个门，年平均丰度为22.13×10个·m，主要以硅藻门（65种，占总物种数的78.31%）为主。浮游植物丰富度指数在0.83至4.99之间，多样性指数在2.03至2.80之间，均匀度指数在0.28至0.84之间。在塔河湾水域，浮游植物丰度和群落多样性与环境参数（包括水温、盐度、pH值、溶解氧、氨氮和硝氮）之间的皮尔逊相关性显著。优势种包括三个门的20个物种，主要为广生态位物种，除夏季外， 为最常见物种。优势种之间的生态位重叠程度随季节变化，在2021年9月为40.0%的严重重叠，2022年3月为100.0%的严重重叠，2022年4月为93.0%的严重重叠，2022年11月为58.0%的严重重叠。冗余分析（RDA）和典范对应分析（CCA）结果表明，化学需氧量、水温、硝氮、溶解性总磷、亚硝酸盐氮和氨氮是影响浮游植物优势种生态位分化的主要环境变量。该研究结果阐明了该海域浮游植物群落优势种的变化规律和群落结构的稳定性，从而为该区域生态健康的科学评估和海洋生物资源的可持续利用提供了理论基础。
