Diverse harmful microalgal community assemblages in the Johor Strait and the environmental effects on its community dynamics
Document Type
Article
Publication Date
7-1-2021
Abstract
Coastal ecosystems are often subjected to anthropogenic disturbances that lead to water quality deterioration and an increase in harmful algal bloom (HAB) events. Using the next-generation molecular tool of 18S rDNA metabarcoding, we examined the community assemblages of HAB species in the Johor Strait, Malaysia between May 2018 and September 2019, covering 19 stations across the strait. The molecular operational taxonomic units (OTUs) of HAB taxa retrieved from the dataset (n = 194) revealed a much higher number of HAB taxa (26 OTUs) than before, with 12 taxa belong to new records in the strait. As revealed in the findings of this study, the diversity and community structure of HAB taxa varied significantly over time and space. The most common and abundant HAB taxa in the strait (frequency of occurrence >70%) comprised Heterosigma akashiwo, Fibrocapsa japonica, Pseudo-nitzschia pungens, Dinophysis spp., Gymnodinium catenatum, Alexandrium leei, and A. tamiyavanichii. Also, our results demonstrated that the HAB community assemblages in the strait were dependent on the interplay of environmental variables that influence by the monsoonal effects. Different HAB taxa, constitute various functional types, occupied and prevailed in different environmental niches across space and time, leading to diverse community assemblages and population density. This study adds to the current understandings of HAB dynamics and provides a robust overview of temporal-spatial changes in HAB community assemblages along the environmental gradients in a tropical eutrophic coastal ecosystem.
Keywords
Diatom, Dinoflagellate, Environmental DNA, HAB taxa, Haptophyte, Raphidophyte, Seasonality
Divisions
ocean
Funders
MOST National Key Research and Development Program of China IHCAS Wuhan [Grant No: 2016YFE0202100],Ministry of Higher Education Malaysia LRGS [Grant No: LRGS/1/2020/UMT/01/1/3],HICoE fund [Grant No: IOES-2014C],UM RU fund [Grant No: RU009D-2020]
Publication Title
Harmful Algae
Volume
107
Publisher
Elsevier
Publisher Location
RADARWEG 29, 1043 NX AMSTERDAM, NETHERLANDS