Temporal and spatial distribution of Microcystis biomass and genotype in bloom areas of Lake Taihu

Dong-Xing Guan; Xingyu Wang; Huacheng Xu; Li Chen; Pengfu Li; Lena Q Ma

doi:10.1016/j.chemosphere.2018.06.141

Temporal and spatial distribution of Microcystis biomass and genotype in bloom areas of Lake Taihu

Chemosphere. 2018 Oct:209:730-738. doi: 10.1016/j.chemosphere.2018.06.141. Epub 2018 Jun 26.

Authors

Dong-Xing Guan¹, Xingyu Wang², Huacheng Xu³, Li Chen⁴, Pengfu Li⁵, Lena Q Ma⁶

Affiliations

¹ State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, China; Key Laboratory of Surficial Geochemistry, Ministry of Education, School of Earth Sciences and Engineering, Nanjing University, Nanjing, 210023, China.
² State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, China; State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, 210023, China.
³ State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, 210008, China.
⁴ Provincial Key Laboratory of Plateau Geographical Processes and Environmental Change, School of Tourism and Geography, Yunnan Normal University, Kunming, 650500, China.
⁵ State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, 210023, China. Electronic address: pengfuli@nju.edu.cn.
⁶ State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, China; Soil and Water Science Department, University of Florida, Gainesville, FL, 32611, USA.

PMID: 29960940
DOI: 10.1016/j.chemosphere.2018.06.141

Abstract

Cyanobacterial blooms as a global environmental issue are of public health concern. In this study, we investigated the spatial (10 sites) and temporal (June, August and October) variations in: 1) their biomass based on chlorophyll-a (chl-a) concentration, 2) their toxic genotype based on gene copy ratio of mcyJ to cpcBA, and 3) their cpcBA genotype composition of Microcystis during cyanobacterial bloom in Lake Taihu. While spatial-temporal variations were found in chl-a and mcyJ/cpcBA ratio, only spatial variation was observed in cpcBA genotype composition. Samples from northwestern part had a higher chl-a, but mcyJ/cpcBA ratio didn't vary among the sites. High chl-a was observed in August, while mcyJ/cpcBA ratio and genotypic richness increased with time. The spatial variations in chl-a and mcyJ/cpcBA ratio and temporal variation in cpcBA genotype were correlated negatively with dissolved N and positively with dissolved P. Spatial distribution of Microcystis biomass was positively correlated with nitrite and P excluding October, but no correlation was found for spatial distribution of mcyJ/cpcBA ratio and cpcBA genotype. Spatial distribution of toxic and cpcBA genotypes may result from horizontal transport of Microcystis colonies, while spatial variation in Microcystis biomass was probably controlled by both nutrient-mediated growth and horizontal transport of Microcystis. The temporal variation in Microcystis biomass, toxic genotype and cpcBA genotype composition were related to nutrient levels, but cause-and-effect relationships require further study.

Keywords: Chlorophyll-a; Horizontal transport; Nutrient level; Toxic Microcystis genotype; cpcBA genotype; mcyJ/cpcBA ratio.

MeSH terms

Biomass
Demography / methods*
Genotype
Lakes / chemistry*
Microcystis / growth & development*