Microbial community changes during a toxic cyanobacterial bloom in an alkaline Hungarian lake

Abstract

The Carpathian Basin is a lowland plain located mainly in Hungary. Due to the nature of the bedrock, alluvial deposits, and a bowl shape, many lakes and ponds of the area are characterized by high alkalinity. In this study, we characterized temporal changes in eukaryal and bacterial community dynamics with high throughput sequencing and relate the changes to environmental conditions in Lake Velence located in Fejér county, Hungary. The sampled Lake Velence microbial populations (algal and bacterial) were analyzed to identify potential correlations with other community members and environmental parameters at six timepoints over 6 weeks in the Spring of 2012. Correlations between community members suggest a positive relationship between certain algal and bacterial populations (e.g. Chlamydomondaceae with Actinobacteria and Acidobacteria), while other correlations allude to changes in these relationships over time. During the study, high nitrogen availability may have favored non-nitrogen fixing cyanobacteria, such as the toxin-producing Microcystis aeruginosa, and the eutrophic effect may have been exacerbated by high phosphorus availability as well as the high calcium and magnesium content of the Carpathian Basin bedrock, potentially fostering exopolymer production and cell aggregation. Cyanobacterial bloom formation could have a negative environmental impact on other community members and potentially affect overall water quality as well as recreational activities. To our knowledge, this is the first prediction for relationships between photoautotrophic eukaryotes and bacteria from an alkaline, Hungarian lake.

A Large-Scale Survey of the Bacterial Communities in Lakes of Western Mongolia with Varying Salinity Regimes

“…Identification of a highly reduced shared microbiome with only five zOTUs with average relative abundance >0.1% among all the lakes belonging to the dominant phyla Proteobacteria and Actinobacteria showcases the cosmopolitan nature of members of these phyla but also points to the tremendous diversity shaped putatively by multiple factors. All these bacterial phyla have been known to harbor bacterial species capable of thriving in various saline environments and contribute a significant proportion of the microbial community in earlier studies as well [23,24,48,[58][59][60][61].…”

Microcystis Chemotype Diversity in the Alimentary Tract of Bigheaded Carp

“…In the several cases where Microcystis and Planktothrix oligopeptide patterns have been investigated worldwide [12,13,14,75,80,81,82], and in our local area [83,84,85,86], the numbers of genotypes have been identified with the help of phylogenetic markers [64,87]. The lack of correlation between the Microcystis chemotypes and phylogenetic genotypes found in cases similar to our present study suggest that the synthesis of bioactive peptides is not phylogenetically conserved in this genera.…”

A Review and Perspective of eDNA Application to Eutrophication and HAB Control in Freshwater and Marine Ecosystems

“…Furthermore, the toxins produced by cyanobacteria have been reported to be a risk to animals, plants and human beings [55]. Bell et al detected changes in the eukaryotic and bacterial communities and their relationships with the environmental conditions in Lake Velence [56]. There is a positive correlation between eukaryotic diversity, such as green algae and diatoms, and dissolved organic carbon (DOC) or dissolved inorganic carbon (DIC).…”