Temperature driving vertical stratification regulates phytoplankton community structure in the Bohai Sea and Yellow Sea

Abstract

To analyse the effects of physicochemical factors on the phytoplankton community in the Bohai Sea (BS) and Yellow Sea (YS), a investigation was conducted during 27 July to 10 August 2020. A sum of 156 species were identified in the BS and YS, including Bacillariophyta (69 species), Pyrrophyta (85 species) and Chrysophyta (2 species). The phytoplankton community were divided into four provinces according to Bray–Curtis similarity. In order to study the phytoplankton community in the BS and YS, we studied the phytoplankton community composition and their assembly mechanisms. The results showed that stochastic ecological processes had a greater effect on the province C community structure. The Raup-crick dissimilarity showed that deterministic factors had a greater effect on the province A, B and D communities structure. The habitat niche width results indicated that niche was larger in the province D, compared to the province A, B and C. Based on a structural equation model (SEM), we analyzed the effects of physicochemical factors on phytoplankton community structure and temperature was found to affect the phytoplankton community composition and structure by the vertical stratification. The result showed that temperature was an important parameter for phytoplankton abundance and revealed that temperature affected phytoplankton community structure by influencing the vertical stratification index (VSI) in the BS and YS.