An ecosystem is a community where the interactions and needs of its components sustain each other. Like every ecosystem, urban ecosystem also works because of inter-dependence of its components with each other. In an urban ecosystem there are 2 main classes of components; biological components and physical components. Biological components consist of plants, animals and other forms of life including human being and their demographical characteristics. Physical components consist of soil, air, water, climate and topography(alignment of land). Humans, of course are an important component in the system. Apart from these, urban components also have man-made components made to fulfil human needs. 

In any ecosystem, the interactions between components gives are crucial for its existence. We are familiar with the popular symbiotic relationship between algae and fungi in lichen where the algae produce organic components through photosynthesis and the fungi consumes it and provides protection for algae’s survival. Urban ecosystems comprise of many such co-dependent systems. Most of these systems involve energy or material transportation between components as interactions. 

Let’s focus on water, which is a key component in urban ecosystem. In a city like Bangalore where there are many lakes, freshwater lakes are one of the biggest sources for water for all organisms. We have plants, fish, algae, water birds which rely primarily on lakes for food, water and a place where they live. Not only these organisms, we humans also depend on lakes indirectly. Lakes being the biggest source of water helps in the water cycle by which we get rain. By rain we can store water using manmade systems like rainwater harvesting, reservoirs, dams etc. Now that we have understood the importance of lakes, its necessary for us to keep to near and pollution free. When pollutants are added to the lakes it disrupts the aquatic lives in many ways, there are chemical reactions by which the water becomes unhygienic and other problems. 

There are adverse effects caused by improper management of lakes. Bangalore’s Bellandur lake catching fire is a tragic example illustrating the ill-effects of an imbalance in water management. Bellandur lake is the largest lake in Bangalore, covering an area of around 900 acres. In the beginning of 2017, residents of south east Bangalore noticed huge plumes of smoke rising into the sky, arising from the lake. They were shocked to discover that the lake was on fire, even the firefighters wondered how to put out a fire on water.

There are multiple factors contributing to this tragic incident in 2017. Bellandur used to be a deserted part of the city, but the rapid development of Silicon Valley in the early 2000s turned this area into a densely populated one. According to studies by the IISc, rapid urbanisation between 1973 and 2016 caused a 10-fold increase in paved spaces, while the city’s vegetation decreased by 88% and the number of water bodies decreased by 85%. 

This rapid growth led to an increase in the number of buildings that were constructed everywhere also in Bellandur. In particular, the topology of that area shows many apartments surrounding the lake. The rise in urban structures implies that there is an increase in untreated sewage that is generated everyday from these apartments. Due to the lack of any other ways to dispose sewage, million of litres of sewage was discharged into the lake. This polluted the water and enabled the growth of several invasive species like water hyacinth in the lake. People also dumped solid waste into the lake. Because of this, an anaerobic environment was created on top of the lake. In anaerobic conditions, the living organisms living in water produced methane. Methane, being flammable, created an ideal environment for the lake to catch fire.

Lakes catching fire is one symptom of an imbalance in the city’s ecosystem. The city is suffering from water shortage.Experts predict that there will be a severe water crisis in Bangalore and that will made the city inhabitable by 2025.The increase in water pollution is polluting the groundwater reserves as well, further amplifying water shortage. The number of water tankers transporting water to apartments has increased to such an extent that the government of Karnataka offered concession on water tanker fee during the summer of 2019. There’s also an adverse impact on the residents’ health. 

There are multiple levels at which the city failed to protect its lakes. First, strict rules should have been implemented to prevent untreated sewage being discharged into the lake. Bangalore has a water supply board and a sewage control board which failed to find systems which treat waste. I think that the speed of development gave very little time for the citizens to adapt methods to treat sewage properly.

Next, the rapid rise of population meant that there was an increase in waste generated and also the manufacture of products increase. This also created the problem of e-waste in the city. Bangalore failed to implement a waste segregation scheme where the residents/corporations segregate waste before handing it over to the municipality. This makes it harder for the municipality to handle unsegregated waste, leading to unregulated dumping of waste into lakes. All residents in the city should sort waste into wet, dry and e-waste and educate themselves about recycling waste whenever possible.

Finally, the increase in population led to the increase in lake encroachments. Because of the dotcom boom, thousands of skilled professionals came to Bangalore search of work. This led to the increase in construction of houses and apartments, and the land prices increased significantly. During this time, many builders/developers illegally encroached land where lakes had dried up. These lands were significantly less expensive attracted the builder to make large profits. People should be educated about the impact of encroaching lakes and building commercial buildings on it, which can help in decreasing the number of illegal encroachments. 

I feel that pollution itself is becoming a cycle through which the environment is affected and it leads to huge damage and destruction of organisms including humans.