Over 300 species of microalgae form blooms – massive populations of microalgae in fresh, brackish or marine waster systems. Approximately a quarter of these species produce toxins.
The blooms can be harmful in that they can result in massive fish kills, seafood contaminated with toxins, and can cause respiratory problems with humans and animals. See my blogs (46 and 86) on my David Border Consultancy website for more information on HABs.
In order to monitor and predict the behaviour and risks associated with HABs it is essential to be able to identify which species of organisms are causing the problem.
One effective way of doing this is to use flow cytometry. This is a process that analyses the physical and chemical characteristics of particles in a fluid – such as cells of microalgae – as they pass through a laser. The light scattered is characteristic of the cells and their components. Parts of the cells can be labelled with fluorescent markets. Many thousands of cells can be checked at at a time with the data analysed, imaged and presented by a computer on a few minutes.
Fluid Imaging Technologies offer the FlowCam system that is used to analyse both freshwater and marine HABs. The system estimates the bio-volume of the bloom, counts the number of cells and calculates the proportion of each type of organism in the bloom. The system can differentiate between many types or organisms including cyanobacteria, diatoms and dinoflagellates.
The company provides a useful series of videos that explains the process in full:
- video that shows how the system acquires data
- video that shows how the images generated by the system are sorted and filtered
- video that shows how an interactive scattergram can be used
- Video that shows how pattern recognition works
- Video that shows how to automatically classify cells
The company also publishes an impressive list of the many scientific publications that have used their technology.
Flow cytometry is a very powerful and fast method of identifying and quantifying which types of organisms are in an algal bloom. This is a valuable aid in predicting the effect of an HAB on the environment, fish life, and its effects on humans and animals.
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