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High‐resolution imaging particle analysis of freshwater cyanobacterial blooms
Author(s) -
Graham M. D.,
Cook J.,
Graydon J.,
Kinniburgh D.,
Nelson H.,
Pilieci S.,
Vinebrooke R. D.
Publication year - 2018
Publication title -
limnology and oceanography: methods
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.898
H-Index - 72
ISSN - 1541-5856
DOI - 10.1002/lom3.10274
Subject(s) - context (archaeology) , enumeration , microscopy , environmental science , instrumentation (computer programming) , magnification , biology , ecology , computer science , physics , artificial intelligence , mathematics , optics , paleontology , combinatorics , operating system
Effective assessment of the health risk of cyanobacterial blooms requires an early warning system, which enables rapid detection of species of concern and determination of whether their cell concentrations exceed advisory guidelines. Advanced digital flow cytometry using FlowCam® (Fluid Imaging Technologies) in combination with light microscopy is a solid prospect for tracking cyanobacterial communities in a timely manner. However, implementation of such a method poses several challenges for the user. We first address sample preparation, instrumentation, taxonomic enumeration, and trouble‐shooting to facilitate high throughput of analyses of water samples for total cyanobacterial cell counts and their species composition. Preservation and initial screening of samples using light microscopy to estimate community size structure are endorsed to insure their archival quality and avoid clogging of the flow cell. We show that the highest magnification (×20 objective) is needed to achieve representative total and species‐specific cell enumerations. We also report that total cyanobacterial cell counts for samples analyzed using FlowCam vs. inverted light microscopy show significant positive correlation, as do those for preserved vs. live samples. Quantification of community composition using FlowCam vs. light microscopy also shows strong concordance. Although our FlowCam method performs well in the context of the World Health Organization advisory threshold of a total cyanobacterial count of 100,000 cells mL −1 , it remains a work in progress in terms of reliably automated species‐level identifications.