Urban problems in developing & developed countries
In developing contries:
Dense traffic, smoky factories, use of wood or coal fires cause excessive air pollution.
Lenient pollution laws, corrupt officials and ignorance cause even more pollution.
Only 35% of urban residents in developing countries have satisfactory sanitation services.
In developed countries
The rapid growth of central cities in Europe and North America has now slowed or even reversed.
The good news is better air and water quality, safer working conditions, fewer communicable diseases.
The bad news is urban decay and sprawl and transportation issues have worsened
Urban Sprawl - is a Current Developed World Problem
In most American metropolitan areas, the bulk of new housing is in large, tract developments that leapfrog beyond city edges in search of inexpensive land.
Urban sprawl consumes about 200,000 ha of US agricultural land annually.
Planning authorities are often divided among many small local jurisdictions.
Most American cities devote ~1/3 of their land area to cars.
Freeways have reshaped our lives.
Public transportation is expensive and difficult to establish.
Ways to achieve urban sustainability
Urban Sustainability in Developed World
Limit city size, or turn into modules of 30-50,000 people.
Maintain greenbelts in and around cities.
Determine in advance where development will take place.
Locate everyday services more conveniently.
Encourage walking and low-speed vehicles.
Promote more diverse, flexible housing as an alternative to conventional housing.
Grow food locally, recycling wastes and water, etc.
Invite public participation in decision-making.
Cluster housing, or open-space zoning, which preserves 1/2 of a subdivision as natural areas (open space).
Sustainable Development in the Third World
Social justice and sustainable economic development are answers to urban problems.
Institution of social welfare providing care to the sick and elderly.
The best way may be for developing countries to delink from international economic systems and develop self-sustainability.
Questions for review:
1. To predict accurately the growth pattern of a human population, why is it not enough to just consider human
numbers? What else must be considered?
2. Characterize four stages of the demographic transition.
Critical Thinking (Writing an essay):
Thomas Malthus in his essay “On population” (1798) argued that human population would be double every 25 years if natural resources were unlimited. How did this observation help Charles Darwin to form his theory of evolution by natural selection?
Humans have tried to control insects with insecticides, such as DDT. Although DDT was effective for the first ten years it was used, the insect population began to increase again. What caused DDT to lose its effectiveness?
Although population growth in some nations has slowed to nearly a standstill, the world population is still increasing at an exponential rate. What might account for this rapid population growth?
Suppose that you want to predict the growth patterns for three small villages, all with the same number of people (the hypothetical example). Draw the graphs and do the assumptions:
One made up of families with children, parents, and grandparents – a population of mixed age and sex, the second is made up solely of children, the third is made up of elderly people.
When determining Earth’s carrying capacity for humans, why is it not enough to just consider human numbers? What else must be considered?
6. How is human population growth related to natural resource depletion and environmental degradation?
7. Discuss some of the ethical issues associated with overpopulation. Is it ethical to have more than two children?
Is it ethical to consume so much in the way of material possessions? Is it ethical to try to influence a couple’s
decision about family size?