Journal Article

The influence of temperature and river runoff on phytoplankton community diversity in Beibu Gulf: insight from 18 S rDNA metabarcoding analysis

Liu, Ying, Xie, Zongsheng, Peng, Chunyan, Jia, Jixin, Qin, Yuyue, Gong, Bin, Xiong, Zheng, Li, Haochen, Liu, Xiaobo, Song, Jingjing

2024

Overview

Background Sanniang Bay (SNB) and Dafeng River (DFR), located in the northern Beibu Gulf, is well-known as one of the eight habitats for humpback dolphins in China. This region is representative of typical estuarine and bay ecosystems and produce complex hydrodynamic seawater conditions. Moreover, anthropogenic pressure, such as eutrophication and large-scale infrastructure projects, have caused ongoing habitat deterioration and loss. It is urgent to know the phytoplankton community and their relationships with environmental factors in this region. Results In this study, we assessed the diversity and assembly mechanisms of phytoplankton communities, as well as their relationship with the physicochemical characteristics of seawater in SNB and DFR region using 18 S rDNA metabarcoding analysis. The results showed that seasonal changes markedly impacted the alpha diversity of the phytoplankton community. From March to July, with the average temperature increasing from 25.2℃ to 28.1℃,the Shannon or Species Richness were negatively correlated with temperature. During hot season (in Sep, average temperature 32.1℃), phytoplankton diversity was negatively correlated with nutrients (NH 4  + , NO 3 − , PO 4 3− , TN). Additionally, during the rainy season, the Bray-Curtis similarity of the phytoplankton community was significantly lower than during the dry season. In March, the distance among the sampling sites was most strongly and positively correlated with the Bray-Curtis dissimilarity. Stochastic processes, specifically dispersal limitation and ecological drift, are the primary drivers of community assembly, while deterministic assembly processes (mainly heterogeneous selection) contribute a relatively minor portion (< 17%). Conclusions Rising temperature diminished the diversity of phytoplankton in SNB and DFR, and nutrient inputs and eutrophication in estuarine areas will aggravate the loss of phytoplankton diversity.

• Publisher: BioMed Central,BioMed Central Ltd,Springer Nature B.V,BMC
• Subject: Analysis / Animal Systematics/Taxonomy/Biogeography / Assembly / Bar codes / Biodiversity / Biomedical and Life Sciences / Carbon / Chemical analysis / China / Climate change / Community assembly / Correlation / DNA / DNA barcoding / DNA Barcoding, Taxonomic - methods / DNA, Ribosomal - genetics / Dry season / Ecosystems / Entomology / Environmental aspects / Environmental factors / Estuaries / Eutrophication / Evolutionary Biology / Genetics and Population Dynamics / Habitat loss / Heterogeneous selection / Human influences / Influence / Life Sciences / Marine ecosystems / Metabarcoding / Nitrates / Nutrient loss / Nutrients / Phytoplankton / Phytoplankton - genetics / Plankton / Rainy season / River ecology / River flow / Rivers / RNA, Ribosomal, 18S - analysis / RNA, Ribosomal, 18S - genetics / Runoff / Salinity / Seasonal variations / Seasons / Seawater / Species richness / Stochastic processes / Taxonomy / Temperature / Thermal properties / Variance analysis / Veganism / Water analysis