Co-regulatory role of Microcystis colony cell volume and compactness in buoyancy during the growth stage
- PDF / 876,827 Bytes
- 11 Pages / 595.276 x 790.866 pts Page_size
- 51 Downloads / 205 Views
CYANOBACTERIAL BLOOMS AND WATER ECOLOGICAL RESTORATION
Co-regulatory role of Microcystis colony cell volume and compactness in buoyancy during the growth stage Huaming Wu 1,2 & Tiantian Yang 1,2 & Chunbo Wang 1 & Cuicui Tian 1 & Oscar Omondi Donde 3 & Bangding Xiao 1 & Xingqiang Wu 1 Received: 2 October 2019 / Accepted: 26 February 2020 # Springer-Verlag GmbH Germany, part of Springer Nature 2020
Abstract The buoyancy of Microcystis colonies determines the occurrence and dominance of bloom on the water surface. Besides the cell density regulation and the formation of larger size aggregates, increases in cell volume per colony (Vcell) and the colony’s compactness (i.e., volume ratio of cells to the colony, VR) may promote Microcystis colony buoyancy. Yet only a few studies have studied the relationship between the internal structure variation of colonies and their buoyancy, and the co-regulatory role of Vcell and VR of Microcystis colonies in the floating velocity (FV) remains largely unexplored. In the present study, we optimized a method for measuring the compactness of Microcystis colonies based on the linear relationship between total Vcell and chlorophyll a. Different relationships between the VRs and FVs were observed with different colony size and Vcell range groups. Both field and laboratory experiments showed that FV/(D50, median diameter)2 had a significant linear relationship with VR, indicating that the cell density and extracellular polysaccharides were unchanged over a short time period and could be estimated via the slope and intercept of a fitted line. We also constructed a functional relationship between FV, VR, and Vcell and found that high VR and Vcell can promote Microcystis buoyancy. This means that increasing cell compactness or Vcell may be an active regulation strategy for Microcystis colonies to promote buoyancy. Therefore, quantifying the internal structure of Microcystis colonies is strongly recommended for the assessment of Microcystis bloom development and their management.
Keywords Cyanobacterial bloom . Microcystis colony . Floating velocity (FV) . Physiological status . Extracellular polysaccharides (EPS) Highlights • Cell volume and compactness of Microcystis colony was dynamic during the growth stage. • Higher cell volume or compactness of Microcystis can promote the higher buoyancy. • Microcystis colony’s internal structure may be related to the active buoyancy regulation. Responsible Editor: Vitor Manuel Oliveira Vasconcelos Electronic supplementary material The online version of this article (https://doi.org/10.1007/s11356-020-08250-0) contains supplementary material, which is available to authorized users. * Xingqiang Wu [email protected] 1
Key Laboratory of Algal Biology of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
2
University of Chinese Academy of Sciences, Beijing 100049, China
3
Department of Environmental Science, Egerton University, P.O. Box, Egerton-Nakuru 536-20115, Kenya
Introduction Microcystis bloom
Data Loading...
