Issue no. 170 - Eutrophication, Cyanobacteria, and Cyanotoxins Newsletter

Microcystis aeruginosa 
(Natural History Museum, London, England)

From the Mainstream Media / Dans les médias grand public

“uPcycle”: Towards a sustainable phosphorus future for freshwater and coastal ecosystems.

“uPcycle will develop a new scalable approach for nature-positive sustainable phosphorus management. This approach will champion re-use and recycling innovations to address biodiversity loss, water quality degradation and societal impacts across freshwater and coastal ecosystems.”

United Kingdom: Government response to the Nutrient Management Expert Group report: Improving policy and practice for agricultural nutrient use and management

“We are continually looking at improving our policy response to tackle pollution from nutrient management and the wider impacts that nutrients can have on the environment and society.”

Sustainable Lake Management Concept wins Frontiers Planet Prize

“The authors explore the complex topic of sustainable lake management, emphasising the necessity of addressing ecological, economic, and social challenges.”

Ontario, Canada: Lake Simcoe restoration projects an exercise in preservation, prevention

“More than 90 projects have been funded since 2004 to mitigate the impact of stormwater runoff by providing infiltration and filtration through projects like stormwater pond retrofits, low impact development and rain gardens.”

Indonesia: 10th World Water Forum formulates priorities in four regions

“Each regional coordinator met at the forum to discuss development and identify priority steps related to the water crisis at the local and regional levels.”

United Kingdom: Mobile Lab Developed to Combat UK Phosphorus Pollution

“A new project, Alternative Approaches to Phosphorus Removal on Rural Wastewater Treatment Works (Alt-P), is exploring chemical free options for phosphorus removal, to reduce the carbon footprint of wastewater treatment, without negatively impacting water quality.”

Virginia, Maryland, USA: Oyster renaissance lifts Chesapeake Bay, but troubles linger

“The Chesapeake Bay Foundation’s “State of the Bay” report card released in January 2023 gave the bay an overall grade of “D+,” unchanged from 2020. Of the 13 indicators assessed, only three improved, while three declined. Oysters did see a gain, but that was offset by a drop for blue crabs, while indicators on pollution and habitat showed little change.”

Interdisciplinary Science Approach for Harmful Algal Blooms (HABs) and Algal Toxins—A Strategic Science Vision for the U.S. Geological Survey

“The U.S. Geological Survey strategic vision is to provide knowledge that supports fundamental and applied understanding of harmful algal bloom proliferation and toxin production through interdisciplinary research and monitoring approach.”

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From the Scientific Media / Des médias scientifiques :

Blue revolution turning green? A global concern of cyanobacteria and cyanotoxins in freshwater aquaculture: A literature review

“Cyanobacterial metabolites (mostly microcystins) were found in aquaculture water and fish from 18 countries (42 and 33 papers respectively). The most affected were small and shallow fish ponds, and omnivorous or carnivorous fish species.”

A non-microcystin-producing Microcystis wesenbergii strain alters fish food intake by disturbing neuro-endocrine appetite regulation

“Dense Microcystis wesenbergii exposure altered feeding rates of native fish. M. wesenbergii disturbed neuro-endocrine appetite signalling pathways.”

Can a shift in dominant species of Microcystis alter growth and reproduction of waterfleas?

“Our study highlights the necessity of including M. wesenbergii into the ecological risk evaluation of cyanobacteria blooms, and emphasizes that consequences to zooplankton may not be clear-cut when assessments are based upon production of microcystins alone.”

The recent disappearance of a persistent Planktothrix bloom: characterization of a regime shift in the phytoplankton of Sandusky Bay (USA)

“The microbial community in Sandusky Bay changes from being dominated by toxic cyanobacteria to non-toxic cyanobacteria. Long-term monitoring of water bodies is necessary to detect changes in water quality and microbial community structures.”

Reservoir regulation-induced variations in water level impacts cyanobacterial bloom by the changing physiochemical conditions

“Water level fluctuations lead to a 50–57% reduction in cyanobacterial blooms.”

Microbial community diversity during algal inhibition using slow-release microcapsules of tea polyphenols

“Results showed that tea polyphenols slow-release microcapsules had strong algicidal activity. When against Microcystis aeruginosa within 20 d, their constant inhibitory rate was up to 99% compared to the control group.”

Exposure to Microcystin-LR Promotes Colorectal Cancer Progression by Altering Gut Microbiota and Associated Metabolites in APCmin/+ Mice

“The mice exposed to MC-LR exhibited a significant promotion in colorectal cancer progression and impaired intestinal barrier function in the APCmin/+ mice compared with the control.”

Cyanotoxin Occurrence and Diversity in 98 Cyanobacterial Blooms from Swedish Lakes and the Baltic Sea

“Microcystin's prevalence was highest with presence in 82% of blooms, of which as a free toxin in 39% of blooms. Saxitoxins were found in 36% of blooms in which the congener decarbamoylsaxitoxin (dcSTX) was detected for the first time in Swedish surface waters at four sampling sites.”

Performance of Selected Commercially Available Asymbiotic N-fixing Products

“Of the 61 site-years, 59 site-years had no yield increase with use of the product over N rate alone. Given the low rate of positive benefits to the use of these products, growers should be sceptical of products that claim to provide asymbiotic/non-symbiotic N-fixation for the purpose of allowing a farmer to decrease fertilizer N rate.”