Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

‘Blue-Green Algae’ Proliferating in Lakes

27.02.2015

The organisms commonly known as blue-green algae have proliferated much more rapidly than other algae in lakes across North America and Europe over the past two centuries – and in many cases the rate of increase has sharply accelerated since the mid-20th century, according to an international team of researchers led by scientists at McGill University.

Their study, published today in the journal Ecology Letters, represents the first continental-scale examination of historical changes in levels of cyanobacteria, the scientific term for the photosynthetic bacteria that form blue-green scum on the surface of ponds and lakes during hot summer months. Cyanobacteria blooms pose a serious threat to drinking-water sources, because certain species contain toxins harmful to the liver or nervous system.


Photo courtesy of Dr. Ron Zurawell, Ph.D., P.Biol. Limnologist/Water Quality Specialist, Alberta Environment

Cyanobacteria, the organisms commonly known as blue-green algae, have proliferated much more rapidly than other algae in lakes across North America and Europe over the past two centuries, according to an international team of researchers led by scientists at McGill University.

“We found that cyanobacterial populations have expanded really strongly in many lakes since the advent of industrial fertilizers and rapid urban growth,” says Zofia Taranu, who led the study as a PhD candidate in McGill’s Department of Biology. “While we already knew that cyanobacteria prefer warm and nutrient-rich conditions, our study is also the first to show that the effect of nutrients, such as phosphorus and nitrogen, overwhelm those of global warming.”

Alpine lakes affected

Researchers from France, Italy, Spain, the UK, Malaysia, and across Canada contributed to the study. While the increase in cyanobacteria in agriculturally developed watersheds was in line with their expectations, the scientists were surprised to find that cyanobacteria also increased in many remote, alpine lakes. In those sites, warmer temperatures and nutrient loading from atmospheric sources are likely to have played a bigger role than direct agricultural runoff.

Dense algal blooms have become a summertime staple of media coverage – and a growing concern of lakefront homeowners -- in certain regions, but until now there had been little in the way of long-term, large-scale synthesis of data on the phenomenon. This left room for doubt as to whether harmful algal blooms were truly on the rise, or whether communities were simply better equipped to identify and report blooms when they occur.

The rapid increase in cyanobacteria identified in the study points to the potential for a parallel increase in the concentration of harmful cyanotoxins, says Taranu, who is now a postdoctoral fellow at Université de Montréal. While potentially toxic species don’t synthesize toxins at all times, studies have shown that one of the best predictors of toxin concentrations in lakes is the total abundance of cyanobacteria.

Cyanobacteria can produce toxins that cause damage to the liver or nervous system. The most common symptoms of acute exposure to harmful algal blooms are skin rash or irritation, gastroenteritis and respiratory distress. Chronic, low dose exposures over a lifetime may also result in liver tumors or endocrine disruption. Preliminary studies also suggest that a recently isolated cyanotoxin may become more concentrated across food chains and may be associated with the formation of progressive neurodegenerative diseases such as Alzheimer’s, Parkinson’s and ALS diseases. Although this latter work is still controversial among scientists, “our results underline the importance of further research in this area,” Taranu says.

Collaborations needed to tackle problem

“Our work shows that we need to work harder as a society to reduce nutrient discharges to surface waters,” says Irene Gregory-Eaves, an associate professor of biology at McGill and co-author of the study. “Because diffuse nutrient loading (as opposed to end-of-pipe effluent) is the main issue, we need to build collaborations to tackle this complex problem. For example, partnerships among freshwater scientists and farmers are starting to happen, and more of this needs to take place, so that we can strike a balance between maximizing crop yields and minimizing excess fertilizer application.”

The research was funded in part by the Natural Sciences and Engineering Research Council of Canada, the Fonds de Recherche du Québec – Nature et technologies, and the Canada Foundation for Innovation.

“Acceleration of cyanobacterial dominance in north temperate subarctic lakes during the Anthropocene”, Zofia E. Taranu, Irene Gregory-Eaves, et al. Ecology Letters, published online Feb. 26, 2015. doi: 10.1111/ele.12420
Link to the abstract: http://doi.wiley.com/10.1111/ele.12420

Contact Information
Christopher Chipello
Associate Director, Media Relations
christopher.chipello@mcgill.ca
Phone: 514-398-4201

Christopher Chipello | newswise
Further information:
http://www.mcgill.ca

More articles from Ecology, The Environment and Conservation:

nachricht How does the loss of species alter ecosystems?
18.05.2017 | Deutsches Zentrum für integrative Biodiversitätsforschung (iDiv) Halle-Jena-Leipzig

nachricht Excess diesel emissions bring global health & environmental impacts
16.05.2017 | International Institute for Applied Systems Analysis (IIASA)

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...

Im Focus: Using graphene to create quantum bits

In the race to produce a quantum computer, a number of projects are seeking a way to create quantum bits -- or qubits -- that are stable, meaning they are not much affected by changes in their environment. This normally needs highly nonlinear non-dissipative elements capable of functioning at very low temperatures.

In pursuit of this goal, researchers at EPFL's Laboratory of Photonics and Quantum Measurements LPQM (STI/SB), have investigated a nonlinear graphene-based...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

Innovation 4.0: Shaping a humane fourth industrial revolution

17.05.2017 | Event News

 
Latest News

A CLOUD of possibilities: Finding new therapies by combining drugs

24.05.2017 | Life Sciences

Carcinogenic soot particles from GDI engines

24.05.2017 | Life Sciences

A quantum walk of photons

24.05.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>