What is Eutrophication?
A process or technique that helps to enhance the constituent amount of nutrients in water bodies is known as Eutrophication. The word ‘eutrophication’ is arrived from the Greek word ‘eutrophos’ that means nourished or enriched.
The enrichment in water bodies somewhat increases the rate of production of phytoplankton and microphytes within the water. This resultantly rises the rate with which the algae grows and at the time of decomposition, the oxygen dissolved in water gets removed.
Basics of Eutrophication
Eutrophication defines the way by which the water bodies get enriched due to the presence of inorganic nutrients resultantly, the growth of aquatic plants increases in water. Eutrophication is considered hazardous to the environment and is one of the most easily spreading ecological issues associated with water bodies existing on the Earth.
One of the major reasons that lead to Eutrophication is human activities that occur near the water bodies. The various anthropogenic activities like modern farming methods along with the high percentage presence of chemicals like nitrogen and phosphorous that causes natural eutrophication of water bodies. Basically, eutrophication leads to deterioration of the water quality as harmful algae gets created and resultantly dead zones are generated.
One should note here that the water bodies that undergo eutrophication turn into dead zones after a point of time and does not support aquatic flora and fauna.
Types of Eutrophication
We have already discussed that eutrophication is associated with the presence of a high concentration of nutrients from fertilizers used in farming, domestic and industrial wastes, sediments, animal wastes, urban drainage, etc.
So, mainly there are two categories in which eutrophication is classified, namely,
- Natural Eutrophication: The nutrient enrichment of lake water leads to cause its natural ageing which is referred to as Natural Eutrophication. At the time of natural eutrophication, the oligotrophic lake is transformed into an eutrophic lake.
- Cultural Eutrophication: This type of eutrophication mainly results from human activities. Basically, human activities cause addition of 80% nitrogen and 75% phosphorous within lakes and streams.
Now there must be a question in our mind that: what are the effects of eutrophication?
- Due to eutrophication various physical, chemical and biological changes take place leading to hampering the quality of water. Thus, one can list the effects of eutrophication as follows:
- When eutrophication happens then the release of toxic chemicals by algal bloom takes place and this leads to killing aquatic bodies like fish, birds that cause sinking of water.
- When the oxygen level of water reduces to zero, then sometimes nitrates are used by some bacteria to derive oxygen while after exhaustion further oxygen is derived from sulphate that leads to producing bad smell and taste of water.
- At the time when algal blooms are decomposed then the oxygen level of water is reduced. This hampers the life of aquatic organisms and water becomes harmful.
- Due to eutrophication, tubificid worms get developed and their high population leads to economic severity in water bodies.
- Sometimes severe water-borne diseases like diarrhoea, typhoid, etc. are the result of the growth of pathogenic microbes, viruses and bacteria on sewage products.
- Another crucial adverse effect of eutrophication is the higher dominance of algae and diatoms because of over-fertilization. As the presence of algae clog filters slows down the flow of water, disturbs the quality of water, etc.
Control of Eutrophication
In order to limit the process of eutrophication following steps can be considered:
- Once algal blooms die and decompose, they must be removed from the water.
- Nutrient enriched water must be diluted to control the hazardous effects.
- By harvest, nutrient recyclability can be checked.
- There are various microorganisms that are known to be efficient scavengers of phosphates. Eight strains of a bacterium can remove phosphates substantially.
Thus, we can conclude that water is known to be an important resource that supports life. However, eutrophication significantly alters the quality of water. Basically, it causes physical, chemical, biological alterations in water bodies. The location where the water bodies exist also impacts the level of eutrophication.
For instance, if a water body is present near large cities then detergent discharges from domestic regions are more likely to increase the level of phosphorous in water bodies. As against, the concentration of phosphorous in urban water bodies is because of agro-activities.