(as in the paragraph below, writer is talking about the image so use same image)
While seeing the above image we will be wondering that these children are swimming in a sea of seaweed which consists of an abnormal algae growth that shows a clear picture of Eutrophication. Seaweed is nothing but the sea vegetables that are various forms of algae growing in the sea, and it is generally eaten in some of the countries in Asia namely, Korea, China and Japan, as it contains lots of fibers.
Eutrophication is the word that has derived from the Greek word eutrophos, which means "well-nourished", has now turned into a major environmental issue. Particularly, phosphates and nitrates formed by the lawn fertilizers make off the land into the lakes and rivers, promoting the algae as well as other plant life growth, which take oxygen through the water, provoking the death of mollusks and fish. Cow manure, detergents, human waste and agricultural fertilizer must be blamed. During 1960s as well as '70s, due to the development of eutrophication in Lake Erie which progressed so incredibly, it turned into a "dead lake". Worldwide many areas around the oceans more than 20,000 sq. miles have become "dead zones", and almost no life of any type exists.
It has emerged as a matter of threat to environment. It is causing degradation of water quality and, is one of the major obstacles to improve the water quality, as marked by the major water quality governing organisations. As per the State of the World’s Lakes Survey, eutrophication has affected 53% of European lakes, 54% of lakes in Asia, 48% of North American lakes, 41% of South American lakes and 28% of African lakes.
Eutrophication, is an enhancement of the water through the nutrient salts which makes some restructuring of the ecosystem like enhanced growth of an algae, exhaustion of fish species, overall deterioration of the quality of water, and also some other serious effects which prevent and reduce the usage of water. Most of the water bodies are subjected to the natural as well as slow eutrophication process, but now–a-days it is rapid due to the activities of the human beings. This is what we call cultural eutrophication.
The eutrophication is the continuous enhancement of nutrients, specifically phosphorus and nitrogen till it surpasses the volume of the water body, activating the structural modifications in the water. These changes in structure mainly rely on several factors as given below.
The following causes are responsible for eutrophication in water bodies.
Agricultural activities in the field as well as the utilization of fertilizers promotes the accumulation of many nutrients in the soil. If these nutrients reach their maximum concentration level, and the soil or ground is unable to assimilate them, then these nutrients are transported by means of rain into the rivers as well as groundwater which flow into seas or lakes.
Release of wastewater into the water bodies:
All over the world, especially in the developing economies, the wastewater is directly released into water bodies like lakes, seas as well as rivers. As a consequence, this discharge of a maximum amount of nutrients provokes the disproportionate algae growth. At the same time, in most of the industrialized nations, wastewater could be illegally but directly disposed into water bodies. As an alternative, water is processed by the usage of water treatment plants prior to discharge into the surroundings, but the treatments implemented are not always like organic load reduction. Consequently, there is an accumulation of nutrients in the environment.
Loss of ability of self-purification: In recent years, maximum quantities of solid matter or sediments. In particular, these sediments are capable to absorb large quantities of nutrients as well as pollutants. The sediments accumulate in the basin which degrades water quality. This observable fact could lead to an additional deterioration of water value, accentuating the processes linked with eutrophication.
Eutrophication is marked by means of a significant raise of algae (microscopic creatures similar to plants) owing to the maximum availability of many growth factors required for photosynthesis, like sunlight, nutrients (phosphorus and nitrogen) and carbon dioxide. In murky water, a large quantity of organic compound accumulates, which is shown by the algae that have attained the end of their life process. To demolish all the lifeless algae, an extreme consumption of oxygen is needed- in some cases approximately the whole of it, by means of microorganisms. An oxygen-free (anoxic) environment is thus formed at the bottom of the lake, with the development of organisms having the capacity of living in an anaerobic (absence of oxygen) condition and responsible for the deterioration of the biomass. These microorganisms, while decaying the organic matter in the absence of oxygen (anaerobic), liberate the compounds which are toxic, like hydrogen sulphide (H2S) and ammonia (NH3). In certain cases, the absence of oxygen disturbs biodiversity with death of living species. These changes are seen when algae degradation is more than the oxygen production, especially during summer.
Effect of Eutrophication
When this eutrophication process becomes predominantly intense, undesirable impacts and environmental disparities are generated.
Bad odors from degraded organic matter which cannot be controlled chlorination in case of drinking water.
Reduction in fish quality causing loss on fishing.
Prospective damage to the drinking water.
Bathing in lakes that is affected by certain algae causes’ skin irritation and it is dangerous.
Reduction in concentration of oxygen, particularly at the bottom of the lake during the end of autumn season and the summer season.
In view of these significant impacts and serious eventual economic as well as naturalistic damage, there may be a clear requirement to curb the development of eutrophication, thereby avoiding the disintegration of the exaggerated ecosystems.