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Blue-green algae and our surface water
Human beings did not invent blue-green algae (also known scientifically as Cyanobacteria). In fact, it’s quite the opposite: we humans in fact, owe our existence to blue-green algae! A very long time ago, blue-green algae nurtured the growth of
life on Earth by producing oxygen. Today, they continue to populate natural
bodies of fresh and salt water. While they are closer to bacteria, they also
have features in common with algae. Blue-green algae proliferation Under some conditions, blue-green algae proliferate rapidly
and form what is called a bloom. The name may seem somewhat poetic, but the
phenomenon is actually quite unfortunate and bears no resemblance whatever
to a flower! Algae blooms in fact, look more like a paint spill, or broccoli
soup: a minute particle or very short strand slurry. Visible to the naked
eye, they are often green or blue-green in colour, sometimes edging towards
red. Near shorelines, blooms rise and amalgamate into surface scum and may
emit an unpleasant odour. In addition to looking repulsive, algae blooms
have the ability to produce toxins. The use that can be made of a body of
water depends on the level of its contamination by these toxins. Blue-green algae proliferation can be triggered by a variety of factors such as elevated water temperature, weak current or water stagnation. However the main guilty party in this story is phosphorus. Phosphorus is an element that is essential to life. It forms part of the basic building blocks of our nutrition, just as it does for animals, plants, algae and even … bacteria! We use phosphorous to fertilize our lawns and gardens and it is employed in agriculture to stimulate crop growth. Phosphorus has a naturally occurring low presence in surface waters. However, many human activities can lead to higher P levels in aquatic environments. Excess phosphorus is found in domestic wastewater and drainage and runoff from deforested land orcultivated fields and shorelines that have been enriched with fertilizers, compost and solid or liquid manure. Eventually, the phosphorus finds its way into rivers and lakes. When present in excessive amounts it stimulates inordinate growth of certain organisms that are native to these bodies of water. Some of these life forms are better than others at making use of this manna: this is the case for many aquatic plants and, unfortunately, for blue-green algae. Recognize it, report it, prevent it Algae blooms may be difficult to distinguish from other aquatic phenomena. This is why the Ministère du Développement durable, de l’Environnement et des Parcs (MDDEP) has produced a helpful guide to identifying them. The guide is available from your regional MDDEP office and on line at www.mddep.gouv.qc.ca Do you believe you have witnessed a blue-green algae bloom? Report it! Talk to your regional MDDEP office about what you saw. Has the bloom you noticed this morning already disappeared? Report it anyway, since blooms move around beneath the surface of the water and can reappear later on in the day or the next day. If you wish to make your action even more efficient you can photograph the bloom and complete the Constat visuel de la présence d’une fleur d’eau form that is available on the MDDEP Website at www.mddep.gouv.qc.ca It is not easy to overcome the phenomenon of blue-green algae proliferation, but the best way is to attack the source of the problem. Above all, we need to avoid an overabundance of phosphorus in our lakes and rivers and there exist simple and easily accessible ways achieve this goal. Here are a few:
Preventing phosphorus overload in surface water and upstream watersheds
remains the best way of countering blue-green algae proliferation. This
preventive action requires collective efforts on the part of citizens,
enterpises and municipal and provincial government authorities. The MDDEP confirms the presence of algae blooms in affected lakes and rivers, takes samples and analyzes them. It also informs public health authorities (DSP), which then issue health advisories as necessary. These advisories allow for timely communication of specific recommendations for the affected bodies of water with respect to limits on water consumption. The ministère de la Santé et des Services sociaux (MSSS), for its part, makes general recommendations on drinking water, swimming and other aquatic and nautical activities available on its Web site at www.msss.gouv.qc.ca. For more information about blue-green algae: Telephone Québec City region: 418 644-4545 Internet | ||||
