Phytoplankton distribution characteristics and its relationship with bacterioplankton in Dianchi Lake

Abstract

Phytoplankton and bacterioplankton perform important ecological functions in lake ecosystem. In this paper, the abundance and composition of phytoplankton and bacterioplankton at 13 sites of Dianchi lake during the wet and dry seasons were monitored, and the relationship between phytoplankton and bacterioplankton in this plateau lake was studied. Phytoplankton community structure analysis was carried out by ocular method, and bacterioplankton was investigated by high-throughput 16S rRNA gene Illumina sequencing. The relationship between phytoplankton and bacterioplankton was observed using redundancy analysis. The results showed that 87 species of phytoplankton belonging to 5 phyla and 29 genera were identified in Dianchi lake. Phytoplankton diversity and richness were higher in the wet season than those in the dry season. In the wet season, Cyanophyta was the dominant phylum whose density was 2.01 × 10 8 cells/L, accounting for more than 90% of the total algae, then followed by Chlorophyta, Bacillariophyta, Chrysophyta, and Cryptophyta. The spatial distribution of phytoplankton in the wet season and dry seasons showed significant differences. In the dry season, the north-central part of Dianchi lake was dominated by Limnothrix redekei and Microcystis minutissima of Cyanophyta, while Pseudanabaena moniliformis and Coelosphaerium nagelianum of Cyanophyta mainly was dominated in the south of Dianchi lake. In the wet season, Microcystis minutissima of Cyanophyta was the dominant species all the area, while Limnothrix redekei of Cyanophyta was second dominant. Proteobacteria and Bacteroidetes were the dominant phyla among bacterioplankton. The community structure of bacterioplankton was influenced by Cyanophyta and Bacillariophyta. Cyanophyta had a major influence on Pseudomonas, Acinetobacter of Proteobacteria, and Flavobacterium of Bacteroidetes. Bacillariophyta showed a strong correlation with Gemmobacter, Stenotrophomonas, and Aeromonas of Proteobacteria. Cyanophyta and Bacillariophyta produced the most significant impact on predicted functional genes of bacterioplankton, and the predicted functional genes of the samples were different in different seasons. Cell densities of Cyanophyta were positively related to metabolism-predicted functional genes of bacterioplankton. Bacillariophyta and Cryptophyta had an impact on most of the cellular processes and signaling predicted functional genes. Bacterioplankton-predicted functional gene information storage and processing were significantly affected by cell densities of Chlorophyta. Therefore, the analysis of the phytoplankton community and the bacterioplankton-predicted functional gene in Dianchi lake exerts a great significance in revealing the ecosystem function of plateau lakes and harmful algal bloom control.

Characterizing free-living and particle-attached bacterial communities of a canyon river reservoir on the Yungui Plateau, China

“…This observation is consistent with one study from this reservoir, which did not separate FL and PA (Yue et al, 2021). Other studies on plateau lakes also reported the predominant role of Proteobacteria and Actinobacteria in the water column (Wu et al, 2019;Zhang et al, 2020). Both groups constitute frequent and highly abundant bacterial members in eutrophic lakes (Trusova and Gladyshev, 2002).…”

“…Only a few studies reported the bacterial community structure in the Yungui-Plateau region, and they rarely separated the FL and PA fractions. Zhang et al (2020) investigated the relationship between phytoplankton and bacterioplankton in Dianchi Lake, which was mainly dominated by Proteobacteria and Bacteroidetes. Wu et al (2019) studied the vertical profile of the sediment bacterial community in Lake Lugu and suggested that chemical variables were the main drivers of dominant phyla.…”

Copper toxicity leads to accumulation of free amino acids and polyphenols in Phaeodactylum tricornutum diatoms

“…The initial cell density used in this study has been reached in some coastal areas (Dursun and Tas 2019 ) and in lake ecosystems (Zhang et al 2020a , b ). Lower phytoplankton abundances commonly observed in coastal waters (Effendi et al 2016 ; Fehling et al 2012 ) could intensify the toxic effects of Cu exposition (Moreno-Garrido et al 2000 ; Singh and Shrivastava 2016 ) affecting the physiological processes of coastal marine organisms and their communities (Leal et al 2018 ; Trombetta et al 2019 ).…”

“…The following 10 amino acids were examined in the cells: Glu, His, Met, Arg, Asp, Lys, Pro, Val, Ile, and Phe. They were selected because of their antioxidant properties (Hwang et al 2019 ) and their role in the response of plants to several types of abiotic stress (Marquis et al 2020 ; Zhang et al 2020a , b ).…”

Environmental DNA metabarcoding revealed the impacts of anthropogenic activities on phytoplankton diversity in Dianchi Lake and its three inflow rivers

“…The phytoplankton compositions of Dianchi Lake were partially consistent with that of previous studies, including the dominant cyanobacteria taxon ( Microcystis ) and the dominant eukaryotic phytoplankton taxa ( Stephanodiscus , Ceratium sp. and Cryptomonas among others; Feng et al, 2020; Wang et al, 2016; Zhang et al, 2021; Zhang, Zuo, et al, 2020). And most of the predominant phytoplankton taxa (e.g., Microcystis , Navicula and Cyclotella ) in the inflow rivers were the same as the historical monitoring results, but there were still some differences.…”