Harmful Aspects of Algae | Biology Teach

In This Article, we discuss the harmful aspects of algae like how algae affect different life forms and cause water pollution. Usually, the excessive growth of algae in a mass or in a large area, especially in the plankton’s or floating form, may cause undesirable effects.

They make the water-blooms(algal networks) which may be harmful for the fishes and other animals; or in water-bodies(reservoirs) may cause pollution and hinder(block) the process of filtration.

Some Algae may grow in abundance(large amount) even in the salt beds and affect the quality of salt, Result in the formation of crystals and in giving a pink or red colour to it.

Water-Nets (Algal-blooms):Harmful Aspects of Algae

When algae grow out of control, they can form large blooms that can cover large areas of water. These blooms can block sunlight from reaching other plants and animals in the water, causing them to die. In addition, algal blooms can release toxins into the water, which can be harmful to humans and other animals.

Excessive development of phyto-plankton or green or blue green algae is often responsible for the water assuming(giving) distinct colours like green, yellow-green(by green algae), yellowish brown(brown algae), dark or dirty brown(blue green algae), reddish brown(red algae), bluish-green etc.

The Red Sea has been named due to the Blue-green algae like (Oscillatoria, erythema, Trichodesmium sp., etc) which gives a red coloration to the sea at the bloom stage or in the algal net formation stage that is formed in case of hydrodectyon.

The red, green, and brown tides in the sea are caused mostly by the Dinoflagellates (having flagella). In freshwater bodies, Algal blooms(water blooms) are fairly common in ponds and lakes and rarely present in rivers, they are caused by a number of classes or forms of algae, (Chlorophyceae, Xanthophyceae, Chrysophyceae, Bacillariophyceae, Dinophyceae, Cryptophyceae, Euglenineae and Cyanophyceae), each giving(imparting) a color of its own.

However, the most common forms of Algae belong to Cyanophyceae (Noclularia, Nostoc, Coelosphaerium, Microcystis, Aphanizomenon, Anabaena, Anabaenopsis, Spirulina, Oscillatoriaetc.).

High pH (7-8-11-0), light, temperature, dissolved organic matter, and low redox potential regulate(governs) the growth of the algal bloom. These Algal blooms consist of many types of algal species, that are ‘mixed’, to form the blooms.

These blooms may be temporary, permanent, or seasonal occurring from November to December and becoming permanent during June or may. Besides giving color to the water the algal blooms may cause disagreeable or unpleasant smell and taste, in this way they make the water unfit for drinking purposes.

If such type of water is drink-ed then it can cause serious diseases. In fish ponds or in fish forms, they may cause physical blocking of the gills and result in the depletion of oxygen during cloudy weather. Large-scale mortality among fishes may also result during their decomposition.

Some very strong poisons or toxins have been extracted from algae that are involved in forming(causing) water blooms (Round, 1966) and reports of the death of cattle and birds drinking such water is also there,

but in another way, chemical analysis of bloom algae or of the water supporting them have not revealed/concluded any toxic substance (Singh, 1955) nor the drinking of such water, with moderate algal blooms, is known to cause any ill effect or disease.

Algal blooms are may be used as manure in certain places, like induced in fish ponds by adding into the inorganic fertilizers(without H and O), to control the submerged weeds(wild plants).

Water pollution

Large growth of algae or algal blooms in water reservoirs or in water bodies that is used for drinking and other purposes causes two undesirable effects :

(i) By giving them a bad taste due to/form their decomposition products.

(ii) By interfering(changing  the normal filtration process and make it abnormal.

Various filamentous(long filament like thallus in multi-cellular forms) and unicellular forms of algae are belonging to the Chlorophyceae, Cyanophyceae, Bacillariophyceae etc. can cause water pollution(changing the water quality). To some degree or in some way,  the presence of certain specific types of algae indicates the nature of pollution and water condition.

Chemical pesticides like algicides(that kill algae or stop the growth of algal bloom), specially copper sulphate with intermittent chlorination are usually employed or used in small doses as a check or measure to the growth of the algae.

In some way algal growth have beneficial effect , specially the attached forms of algae, in the reservoirs or water bodies with hard or calcareous mass formed ‘water is the precipitation of carbonates(carbon containing compounds) and reduction in the hardness of water.Harmful Aspects of Alg

Disease Causing Algae :

Certain plants that having great economic importance like (Tea, Coffee, Citrus etc.) are sometimes seriously affected by the parasitic alga(parasitic algae). Cephaleuros. C.virescens causes the red-rust of tea, one of the most common disease of tea-plant (Thea sinesis).

These parasites are most destructive as a stem parasite(afeect the stem of plant) and can cause damage when the host is growing slowly. Another species of Cephaleuros, C.coffea is parasitic on coffee plants and causes diseases in coffee plants.

Oxygen depletion:

Some types of algae consume large amounts of oxygen as they grow, which can lead to oxygen depletion in the water. This can be harmful to other aquatic plants and animals, as they need oxygen to survive.

Invasive species:

Some types of algae are invasive species that can outcompete native plants and animals for resources, leading to their decline.

Eutrophication:

Algae can contribute to eutrophication, a process in which excess nutrients in the water lead to an overgrowth of algae. This can lead to a decline in water quality and can be harmful to aquatic life.

Human health risks:

Some types of algae can produce toxins that can be harmful to humans if ingested or inhaled. In addition, algal blooms can affect the quality of drinking water and the taste and smell of seafood.

Related Questions

Refrences:

• https://www.biologydiscussion.com/algae/economic-importance-of-algae-botany/53422
• britannica.com
• https://www.intechopen.com/chapters/41950
• https://www.health.ny.gov/environmental/water/drinking/bluegreenalgae/
• https://www.epa.gov/nutrientpollution/harmful-algal-blooms
• https://www.betterhealth.vic.gov.au/health/healthyliving/Harmful-algal-blooms
• https://deq.utah.gov/water-quality/health-effects-of-harmful-algal-blooms