The explosion of the human population is said by some to directly cause or be caused by the increase of industrialization. It seems like industrialization and population explosion both have a positive effect on each other up to a certain point. The most noticeable effect of such changes is the creation of cities, which are the centers of population density, and usually of the productivity and industrial areas of a region or country. This paper will examine some of the commonly seen effects that an increase in industrialization in conjunction with a population explosion in the form of a city can have on the environment.

The concentration of masses is sometimes seen as a requirement for industrialization to actually occur. Though the precursors of industrialization sometimes include the majority of the concentration of people in the countryside moving to cities, this can often begin after the very humble beginnings of industrialization are seen. Regardless, for industrialization to actually progress to a significant extent, large numbers of people must move to one area which usually serves as the node for technological development as well as cultural growth for a long time afterward.

The large numbers of people usually have two effects on cities that are already present or soon come to exist in those areas. The first is the increase in population density which generally has several effects. First is the creation of large scale living developments. This generally requires the absence of most if not all kinds of plant and animal life in that area. The results by diffusion are a lower concentration of animals in the area of the city as well as the region surrounding the city.

One result of the combination of large numbers of people in a high density area is the necessity for large scale drainage systems. Because a large scale and functioning water system is rarely in place before the introduction of the population, there is usually a period of very harsh health conditions within the city. Stagnant bodies of water are far from uncommon and are breeding grounds for insects such as mosquitoes which thrive off of the conditions and end up carrying disease throughout the population. From the city, disease is often carried to the countryside and other cities through trade. The ultimate result is a fluctuating population which consequently introduces varying amounts of thermal pollution into the nearby water systems. In addition, patches of uninhabited land can be found around the city that serve as areas for foreign species introduced by trade to breed. The diffusion of the species can then affect the native species of the area.

Another major effect of the creation of cities is the creation of roads and other developed land. Probably the most noticeable effects are the elimination of drainage area and the loss of animal habitat. Another less discussed effect of cities is the creation of thermal disturbances. Thermal images of the tops of buildings and pavements appear in sharp contrast to the readings from forest cover, fields, and even dirt. On a large scale this thermal pollution can result in changes in the local and nearby climates. The effects of a climate change can be as severe as a total restructuring of a local ecosystem including the primary producers. Any crops being grown in the surrounding area are put under stress, but because the price would be too great to move a farm, most farmers use some kind of high potency fertilizer and irrigation techniques to control the condition of the farm land.

Another basic effect of industrialization is the high level of pollution pumped into the surrounding environment. The immediate effects are generally very few for the surrounding ecosystem because of the diffusive effect of forests and the ability of streams and the wind to carry pollution away. However, over time sinks such as forests and lakes get filled up and start to show negative effects. The general effect is a loss of plant an animal life and the introduction of hardier species, or even the desertification of an area once trees die out and erosion sets in.