Urbanization can be defined as the process of small, rural settlements growing and expanding to become urban centers. Such an evolution is typically the result of some sort of economic incentive in that the prosperity of a given community attracts the attention of people interested in sharing in or profiting from the success of the established community. As more people attach themselves to the prosperous community, the population swells and matures to eventually create a city. In more modern times, urbanization can also be understood as the increase in the number of people residing in urban locations.
The size of modern cities, some of which are expected to have populations of more than 40 million, was likely unimaginable 200 years ago when only approximately 2-3% of the population lived in cities. The massive increase in urban populations ergo urbanization can be attributed to the development of agriculture as it allowed populations to expand beyond the carrying capacity of a natural environment. Advancements from industrialization and the Green Revolution further catalyzed population growth and migration towards urban spaces. The trends influenced by these developments include:
- A shift from northern to southern population growth: the majority of population growth now takes place in the southern hemisphere (Africa, Asia & South America) rather than the northern hemisphere (North America & Europe)
- A shift from formal to informal: there is a change from organized labor and living to lifestyles which require the generation of individual prosperity
- A shift from city to megacity: cities are expanding to house more than 10 million residents
Currently and since the first cities of Uruk (4500 BCE) and Ur (3800 BCE), urban spaces have been locations that greatly impact the surrounding environment as these spaces are inherently not self-sustaining due to the great number of inhabitants and the many needs, e.g. food, of said inhabitants. Accordingly, the downfall of many great cities can be attributed to overpopulation and environmental damage caused by overexploitation. Such downfalls could arguably be viewed as a justification for proactively addressing many of the issues faced in cities in modern times, e.g. sanitation or food waste, especially in locations where populations continue to grow despite lacking the environmental capital necessary to sustain existing populations.
Modern and rapidly urbanized cities suffer from other issues, including:
- Increases in urban poverty and inequality that could result in a weakened state, civil unrest, urban-based revolutions, and radical religious fundamentalism
- A shortage of living wage income-earning opportunities
- A lack of livable spaces
However, despite many negative issues associated with urbanization, the social, cultural and economic opportunities, as well as the convenience of cities, is unparalleled by rural environments. Therefore, it is almost certain that urban populations will continue to grow with it being expected that by 2050, 64.1% of the citizens in developing lands and 85.9% of citizens in developed lands will reside in cities. Such a transformation will provide both challenges and opportunities for the future. How these issues are addressed at present will guide the way by which the urban epicenters of the future will impact not only the human citizens of the world but also the flora and fauna that cohabitate the earth.