Proudly flaunting a standing Buddha, in the middle of the twin cities, lies an engineering marvel, the Hussain Sagar Lake. Situated between Hyderabad and Secunderabad , the lake, more than 450 years old, was once a source of drinking water. The lake hydrology is sustained by four major feeding channels. Thanks to rapid industrialization and urbanisation, the age old lake today is a victim of the loss of biodiversity, recurrent fish kills and extensive pollution. Sewage and water wastes have increased the levels of certain chemicals like Nitrogen and Phosphorous. Harmful algae blooms are one of the visible symptoms. It also proved toxic to fish and altered the food chain. Measures are being taken to restore the lake’s environment. If it gets any worse the statue of the standing Buddha will cry out loud!
This is just one example of an intensifying environmental issue, known as Eutrophication.
Eutrophication is a result of excessive chemical nutrients in a lake or other body of water, usually caused by the runoff of nutrients from animal wastes, fertilizers or sewage. It leads to the bloom of plankton such as algae, and depletes oxygen in the water. Water with low concentrations of dissolved oxygen is said to be hypoxic. Harmful algae blooms affect the environment in two ways. First, they introduce toxins, some of which have no antidote, killing fish and harming humans. Secondly, they result in high biomass accumulation, hypoxia, anoxia and the shading of submerged vegetation.
Man does it yet again!
With each passing day, we seem to be taking one step away from nature.
Eutrophication results from aqua cultural activities and other human activities on coastal ecosystems. Fertilizers applied to agricultural fields and suburban lawns, deposition of nitrogen from the atmosphere, erosion of soil containing nutrients and sewage treatment plant discharges are major contributors.
This does not merely affect the ecosystem in water bodies. The toxins are consumed by aquatic creatures, and we in turn consume them. It then enters the food chain. Even if a majority of the population is no longer sensitive towards the environment in which we live, at least the fact that it indirectly affects man should be reason enough to make heads turn in this direction.
A global issue
Statistics reveal that over 54% of the lakes in Asia, 53% in Europe, 48% in North America, 41% in South America and 28% in Africa are Eutrophic. The World Resources Institute has identified 375 hypoxic coastal zones in the world, concentrated in coastal areas of Western Europe, the Eastern and Southern coasts of the US, and East Asia, particularly Japan.
The first step would be to ban activities, in the concerned areas, that cause pollution. This will automatically reduce levels of carbon, nitrogen and phosphorous. The accumulated pollutants, both organic and inorganic must be cleaned. This in turn will gradually curb the growth of algae. Artificial aeration can increase the dissolved oxygen in the water body.
In the long run, it has to be the joint effort of citizens. The long term solution is to create awareness among the general public. This is just one of the innumerable environmental issues that the world is facing today. We need to modify our lifestyles. Rather, we need to travel back in time; to an era when we lived in harmony with nature… an era that is distorted beyond recognition.