According to Researchers Used Underwater Drones To Study Algal Blooms, researchers using underwater drones have identified the process behind the formation of algal blooms. They say that these “new findings could offer hope to teams seeking ways to address toxic algal blooms”.
The researchers found that algal blooms “develop from a bottom-up sequence driven by sediment plumes generated by rainfall”. Dr. Troy Yu Tao, associate professor at Harbin Institute of Technology, said, “This study fundamentally changes how we understand algal bloom initiation.”
Their autonomous underwater drone equipped with high-precision sensors collected more than 2.8m data points over four months, assembling a high-resolution, three-dimensional portrait of the water column. Findings included “identifying the life cycle of an algae bloom in these three distinct phases: –
Heavy rainfall agitates the water, churning the sediment and lifting dormant algal cells and stored nutrients back into the water column
Instead of dispersing, the cells coalesce into coherent plumes: dense vertical columns of biomass that steadily move upward toward the light.
After about one to two days, these plumes reach the surface, spread outward, and develop into visible blooms that can be seen with the naked eye.
The original research can be found at https://www.sciencedirect.com/journal/environmental-science-and-ecotechnology/vol/29/suppl/C .
(Photos taken by David Muirhead)