Environmental problems: To some people the city represents humanity’s triumph over nature. Certainly it is a radical change of nature. What was once field or forest is covered with pavement and buildings. Natural balances of air, water, soil, and even noise are fundamentally altered. The very existence of large cities, in addition to all the activities that go on in them, has perhaps permanently altered the global environment.
With all of the conveniences of city life, many urban residents forget that cities cannot exist on their own. Some have even naively claimed that all of the world’s people could settle in a single megacity smaller than the state of Texas. But where would these billions of people grow food? Or work? Or dispose of their sewage? Or breathe clean air? They would not have access to enough open space or natural resources, and an environmental and social catastrophe would result. A city has to be understood in the context of its surrounding region.
"City." Britannica School, Encyclopædia Britannica, 8 Feb. 2018. school.eb.com/levels/middle/article/city/273680#234536.toc. Accessed 14 Oct. 2022.
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