The human population is increasing ip the last few. hundred years. Humans are sing resources to provide need and wants for the growing population. But humans have lost the sense that they are also part of world. ecosystem. They are wasting world resources. It has created many ecological problems.
HUMAN POPULATION GROWTH
Carrying capacity of the earth
he increasing human population is the root of all environmental problems. Human populations are growing exponentially. The earth has a carrying capacity. I has a limited supply of resources. The populations should stabilize at carrying capacity. But this population does not stabilize. Therefore, it creates problems Ii e misery, war, famine and diseases.
he carrying capacity of the earth is not fixed. It depends on the desired standard living. But the resources are not distributed equally among all populations. The current population of the earth is 6.1 billion. All environmentalists agree that this umber is too high.
Age structure and age pyramids
I tense efforts are made to control population growth. Otherwise world population will double in the next 50 years. The age characteristics of world populations explain .why human populations will grow rapidly. The age structure a population shows the proportion of Pre reproductive, reproductive, and postreproductive classes. Age structure is represented by an age pyramid.
( ) Age pyramids in developing countries: The -age pyramid has a broad base in the developing countries.. It indicates high birthrates. But they have high infant mortality. It offsets these high birthrates. Some developing countries adapt modern technologies. These technologies reduce prereproductive mortality. It prolongs the life of the elderly people. But reproductive practices changes. Therefore, population explosion occurs. Unfortunately, cultural practices change slowly. Therefore, people does not use modem birth control practices.
( ) Age pyramids in developed countries: Population growth is slower in developed. countries. Therefore, the proportion of the population in each reproductive class is balanced. The American uses modem birth control practices. Therefore, birthrates in the United States have decreased in recent years. But still the U.S. population is now at about 272 million. It is still growing. Immigration is increasing population in the United States. About two million legal and illegal immigrants arrive per year in the US. Therefore, the U.S. population will increase to 500 million by 2050. The current standard of living can support only 200 million people. The government is trying to support too many people at the current standard of living. It is causing homelessness, hunger, resource depletion, and pollution.