Blue – green algae are scientifically known as cyanobacteria. They are also known as pond scum. They belong to the family of bacteria and naturally develop in shallow, warm and still waters. These conditions are present in fresh water lakes, ponds, and wetlands. In order to survive and grow the algae blooms need sunlight and thus they are photo synthetic bacteria. The name blue – green algae can be attributed to the fact that the first species of this algae were blue – green in color. There are other types of algae, namely, olive – green colored and red colored.
During the months of July and August, the population of the algae grows enormously due to the fact that the congenial conditions of hot, calm weather are fulfilled in these months. These weather conditions help create large numbers of blue – green algae, which are often called blooms. These blooms incline upwards to the surface of the water and cover the water. They resemble thick pea soup that is blue – green in color and they occur naturally. A large portion of blue – green algae blooms are either toxic or poisonous. Wildlife, livestock or humans who consume these algal blooms could possibly die (Blue-green Algae Blooms.
BC HEALTH FILES). The cyanobacteria have a dual effect on humans. One variety of these algae acts as a natural fertilizer for rice, whereas there are other variants of this class of bacteria, which contain dangerous toxins. The toxins of cyanobacteria cause a rash in humans. Some cyanobacteria emit high levels of neuromuscular toxins, which kill the fish that consume it. The water containing such algae, on being consumed by animals proves to be fatal. If conditions are favorable, the cyanobacteria grow in profusion and such dense algal blooms produce potent toxins that render seafood highly poisonous.
The people who consume such seafood are bound to die. Algal blooms cause a discoloration of water and impart a malodorous smell and a bad taste to it (Steinman). During the summer season, algae blooms develop on the lakes and other reservoirs in the entire region and the blue – green algae grow abundantly on the water. They need combinations of high levels of nutrients, warm water, and prolonged sunny weather conditions. These algae make the water become odorless or pungent and the taste unpleasant. Eventually the water becomes unfit for human consumption.
The various recreational activities on the Lake of the Prairies are severely hindered in summer, because the algae blooms grow abundantly on the water in summer. In Brereton Lake in the Whiteshell, the fish population was killed by the algae blooms, in the year 1990. During summer, the huge population of algae blooms in the Shoal Lake renders the water tasteless and causes a severe drinking water problem in Winnipeg (State of the Environment Reports). The blue – green algae blooms contain two different types of toxins. One type consists of neurotoxins that interfere with the nervous and respiratory systems of human beings.
These neurotoxins cause muscle tremors, stupor, staggering, rapid paralysis, and respiratory problems. Consuming these toxins generally results in death within thirty minutes. A number of dead bodies of animals that have consumed the water, contaminated with the algal blooms, can be found near water bodies like lakes and ponds. The consumption of these algal blooms is fatal irrespective of whether an animal or a human consumes them (Blue-green Algae Blooms. BC HEALTH FILES). The other type of toxins is the hepato – toxins. These toxins damage the liver which results in
Animals or humans who drink water contaminated with toxic strains of blue – green algae blooms would die within thirty – six hours. Jaundice and sensitivity to sunlight are the immediate symptoms of these toxins. Animals that consume water containing this toxin develop these symptoms (Blue-green Algae Blooms. BC HEALTH FILES). Harmful Algae Blooms cause great economic loss. They hinder activities such as commercial fishing, tourism, cultural traditions, recreational, and subsistence harvests. Maryland sustained a huge economic loss in the year 1997 due to such contamination.
The seafood industries depicted a decline of over ten percent of their gross sales due to harmful Algae Blooms in the water. This industry had been making huge profits with an annual rate of increase of seventy – four percent till 1996. The reduction in sales was approximately forty – three million dollars. This huge loss was attributed to the Pfiesteria toxins of the algae blooms. In addition, persons who had been affected by this localized toxic outbreak of Pfiesteria developed several neurological diseases ( Harmful algae blooms in Mary land ).
Furthermore, algal blooms cause the discoloration of water, formation of foam on the water, depletion of oxygen, and death. Some fish such as benthic fauna and wild or caged fish or shellfish get poisoned and consuming those fish results in death. The uncontrolled growth of plankton algae causes organic matter to accumulate at the bottom of the water bodies. The ecosystem is adversely affected and the local biodiversity is harmed due to the uncontrolled growth and preponderance of filamentous macroalgae. The growth of these algae is due to the presence of excessive nutrients in the water (European Environment Agency).
Domestic water supplies in the cities Brandon and Morden depend on the Assiniboine River and Lake Minnewasta. Algae blooms on these water sources result in the loss of taste and odor in this water. The water department in Brandon increased the rate of chemical feed at the water plant in order to manage this problem. In Morden, the staff added copper sulfate to Lake Minnewasta to eradicate the algae. Although these problems prevail for a short period, the residents of the cities have to countenance a great deal of inconvenience. Consequently, the people commenced to depend on other sources of drinking water (State of the Environment Reports).
With the advancement of scientific knowledge, humans are deriving a number of advantages from the algae blooms. Some of these advantages include the production of food for people as well as animal livestock, using them as binding agents in the preparation of ice creams and shampoos, and using the algae in medicines to control certain diseases. Commercial farming of over 150 species of algae as a vital source of food is one of the positive aspects of the algae. In Japan, China, and Korea people consume seaweed that has been prepared by using algae.
The revenues from such seaweed have been estimated at $2 billion per annum. Nori a red algae is a very popular item of food in these nations (Steinman). In North America and Europe, seaweeds are food supplements for animals. Some species of cyanobacteria are rich in proteins. Spirulina is very popular in this respect and it is grown in ponds commercially. Spirulina is considered to be a health food and cattle dietary supplement. Seaweeds are a very rich source of concentrated potassium and trace elements; therefore, they are used as fertilizers and soil conditioners, in order to increase crop production.
Another species of cyanobacteria converts atmospheric nitrogen to ammonia, which is a very useful plant nutrient. Growing cyanobacteria is a major agricultural activity in the tropical countries, because it provides nitrogen to rice (Steinman). Eutrophic reservoirs generally contain cyanobacteria, whose blooms destroy the aquatic environment and prove fatal to animals and humans. They are largely prevalent in water bodies all over the world. In South America, these cyanobacteria have caused the death of a very large number of fish and aquatic life.
For example in Chile the blooms of these bacteria produced microcystine L – R production, which caused an enormous destruction of aquatic life. Similarly, in Brazil, PSP phycotoxins were present in large quantities in water. Moreover, these cyanobacteria have produced hepatotoxins like Microcystis that resulted in severe ailments of the liver (Paralytic Shellfish Poisoning Phycotoxins: Occurrence in South America ). Blue – green algae are as widespread as bacteria and are found to a large extent in either neutral or alkaline Eutrophic fresh water plankton and in the plankton of tropical seas.
The benthic forms are usually found in hot springs, snow, ice, tree trunks. Cyanophyceae live in symbiosis with several animal and plant species. Moreover, the phycobiont of a large number of lichens is made up of these Cyanophyceae (Cyanophyceae. McGraw-Hill Concise Encyclopedia of Science and Technology). Apart to forming important contributors to food chains, a number of benefits are obtained from the blue – green algae. One such important activity is the fixing of Nitrogen in the soil so that rice paddies are enriched to a significant extent.
Nevertheless, these blue – green algae are a veritable pestilence on occasion, for instance, they impair the function of filters by clogging them, make domestic water supplies unfit to drink due to engendering bad smell and taste, render swimming pools, aquariums and fountains unusable and cause the death of birds, fish and domestic animals (Cyanophyceae. McGraw-Hill Concise Encyclopedia of Science and Technology). Some of the earliest forms of life on this planet consisted of these blue – green algae and their fossils have been discovered in rocks that had been determined to be around 2.
3 billion years old. Furthermore, the accretion of oxygen in the earth’s atmosphere has been attributed to these blue – green algae (Cyanophyceae. McGraw-Hill Concise Encyclopedia of Science and Technology). It is essential to identify and monitor water bodies that contain algal blooms, in order to ensure that the quality of the water does not deteriorate. However, there risk of the occurrence of these blooms cannot be entirely eradicated and it is the duty of the water managers and the general public to keep a close watch over these water bodies so that any algae bloom can be detected.
Further, a proper course of action has to be implemented, which will deal with blooms and their resultant problems in an appropriate manner (Algal Blooms – Causes and Management. Victorian Resources Online ). Harmful Algal Blooms or HABs cause significant harm to the economy, ecology and society, it has the potential to cause the death of shellfish, dolphins, manatees and humans. These HABs contain toxins that on becoming airborne make breathing difficult in people, which leads to a decline in the number of people visiting the seaside.
Over a period of time almost all the coastal states have fallen prey to the depredations of these algal blooms. The gravity of the situation can be gauged from the fact that advanced detection techniques are being employed to detect and control these blooms and examples of these are biochemical detectors, computer simulated models and satellites. Nevertheless, the fact remains that loss to the tune of millions of dollars takes place annually due to these algal blooms (Mitigating Harmful Algal Blooms ). Works Cited Harmful algae blooms in Mary land . 16 July 2007 <http://www. dnr. state. md. us/Bay/hab/ >.
Algal Blooms – Causes and Management. Victorian Resources Online . 9 July 2007. 16 July 2007 < http://www. nre. vic. gov. au/DPI/Vro/vrosite. nsf/pages/water-river-algal-manage>. Blue-green Algae Blooms. BC HEALTH FILES. 16 July 2007 < http://www. bchealthguide. org/healthfiles/hfile47. stm >. Cyanophyceae. McGraw-Hill Concise Encyclopedia of Science and Technology. 2004. 16 July 2007 <http://www. credoreference. com/entry/5969040 >. European Environment Agency. Algal bloom in coastal waters. 16 July 2007 <http://www. eea. europa. eu/highlights/20030811104233>. Mitigating Harmful Algal Blooms .
1 February 2007. 16 July 2007 <http://pagebang. com/cgi/nph-proxy. cgi/111011A/http/celebrating200years. noaa. gov/transformations/habs/welcome. html>. “Paralytic Shellfish Poisoning Phycotoxins: Occurrence in South America . ” Comments on Toxicology (2003): ISSN: 0886-5140. Vol. 9. Pp. 175 – 193. State of the Environment Reports. Algae Blooms Perennial Problem of Water Supplies on the Prairies. 16 July 2007 <http://www. gov. mb. ca/conservation/annual-report/soe-reports/soe91/stories. html>. Steinman, Alan D. “Algae. ” In Microsoft® Encarta® 2006 [DVD]. Redmond, WA: Microsoft Corporation, 2005 .