Human Population Explosion

Introduction

Homo sapiens, the humans are relatively recent arrivals in Earth’s history.

But their influence on the environment is very great.

The explosive growth in the human population has had dramatic consequences for the environment and for other organisms

How quick is the population growing???

It’s just like a explosion!!!!!

Rate of increase = births - deaths

The population has grown at an ever-increasing rate!

Though birth rate remains constant or has a slightly drop, but the death rate drops rapidly.

The Human Snowball

“Population Explosion”

-Human population grows so fast

->>exceeds the carrying capacity of the environment

>> human lives are threatened.

More and more people live on the Earth,As a result , a large numberof human may die.

Cause Of Overpopulation

1. Change in methods of food production?

2. Agricultural Revolution?

3. Industrial Revolution?

4. Progress in medicine?

1st increase in population growth rate:Age of colonization begins(More space for living)

2nd increase in population growth rate:Agricultural + Industrial Revolution(Food production increased)

3rd increase in population growth rate:Medical Revolution(Mortality Rate decreased)

The significant rise in population growth rate

The Domino Effect of the development of humans

Industrial Revolution

Agricultural

Revolution

Food production

increase

Population

increase

Industrial Revolution

Medical

Revolution

Mortality rate

drop

Population

increase

The other Domino Effect

•Control of harmful bacteria made water safer to drink•Sewage disposal systems•Things for daily use are made which could be easily washed•The new medicine was introduced•Living Standard improves

Problem posed by overpopulation

Ⅰ Social Problems

Ⅰ World Food Problem

Ⅰ Impact to Environment

1. The Social problem of the overpopulating

Over-crowded Conflict --> war “Aging” problem in developed countries Other moral problems

Those would not be discussed deeply, just be mentioned only.

2. The World Food ProblemWhich is the most serious social problem of the overpopulating

1. Political instability

2. Unfair trading policy

3. Uneven distributed food supply

4. Unbalanced population distribution

5. So much food is wasted

6. Deforestation inhibits food production

7. Natural disasters

Famine in less-developed countries

1. Political instability:

- Hinder the export and import of food in the less-developed countries

- War destroy the agriculture less food produced

2. Unfair trading policy:

the government and businessman from well developed countries ( such as USA) deprive the less-development countries by selling the low cost food to destroy the agriculture of those countries.

The cause of world food problem

4. Unbalanced population distribution: population of less-developed countries >>> population of well developed countries consumption(well developed countries)>>>consumption(less-developed countries)

3. Uneven distributed food supply: Though food production is increasing faster than the population.

-- 1/3 world population (well developed countries) consume ½ world food supply

5. So much food is wasted: Wasteful eating habits of the people

6. Deforestation inhibits food production: Soil erosion -> soil no longer fertile

7. Natural disasters:

Droughts, floods, pests

Slow-down of food production

Africa Food Crisis If the population still keep on increasing,

the food problem will be worsen

Source: USAID. Executive Overview of Food Security in Sub-Saharan Africa, 15 Feb 2006; for Burundi figure, News from Africa 1.4millionZambia

3.7millionTanzania

2.1millionSomalia

801000Mozambique

4.9millionMalawi

3.5 millionKenya

> 10 millionEthiopia

230,000Djibouti

2 million Burundi

Population at risk

Country

How to solve this problem?

•The food aids

•Teaching the agriculture technology to the people in those countries

•GM food !!!

•New policies to the agriculture and trading system.

•Reduction of energy loss and food loss -reduce the energy loss during TROPHIC TRANSFER , such as eat plants -reduce the waste of food

GM engineering

Genetic engineering, genetic modification (GM, 基因改造 ) and gene splicing are terms for the process of manipulating genes, usually outside the organism's normal reproductive process.

GM food

Genetic Modified food can benefit the food in the following categories:- Taste- Yield- Nutrition value

III. Impact to the environment

The environment has largely destroyed by us. There are a lot of environmental problems. Air pollution, land pollution and water pollution.

As the human population increase, the demand of natural resources increase as well.

Air Pollution-Carbon monoxide -Sulphur dioxide-Nitrogen dioxide-Hydrocarbons -Ozone -Particulates

Land Pollution-Waste disposal

-pesticides

Water PollutionToxic chemical

Oil

Deforestation

A large area of forest was pulled down by humans.

Lots of organisms lost their habitat. Soil erosion Desertification

The community of Hong Kong disposes about 17,900 tons of solid wastes every day. Of this, 7,500 tons are domestic waste, 1,800 tons are commercial and industrial waste and 7,500 tons come from construction activities. The municipal waste production amount of each person is about 1.4 kilograms per day.

Hong Kong only got a population of 7 million, can you imagine the amount of waste produce each day in the World, which got a population of 14 billion?

Green House Effect In 2006, the average temperature or Hong

is 23.6 , which is the highest record. Increasing concentration of greenhouse

gases Lead to Global warming

Exploitation of resources

Renewable Resources – resources that can be regenerate fairly rapidly through natural processes. E.g. Oxygen, Minerals in soil.

Non renewable resources – resources that limited in availability. They are fixed in total quantity in the Earth’s Crust and are not replenished by natural processes in short time.E.g. Fossil fuels

Are you noticed our resources are consuming? Resources like coal and oil are non

renewable. Once they had depleted, we will lost the access of almost all our technology.

Why should have population control?

The critical question is: In the present of such a huge human population, can the natural environment be maintained in a condition that will supply all living things with the required food, water, and space?

An immediate task must be to reduce the birth rate.

Population Control

The Earth has its capacity, its resource will be used up one day. if the population keep on increasing, the problem of food and the problem of pollution will be worsenControlling the population is critical to saving the environment from hazards of pollution.

Population Control PolicyChina : one family one child

Hong Kong (past): 2 children is enough

India :-in the mid 1970s -concentrated on male sterilisation. -strong resistance developed to the concept family planning.

Tunisia and Jamaica: -improved the provision of freely available family planning advice and materials. -introduction of education skills and a general raising of the economic-improved the health of mother and the child by preventive medicine.

Conclusion

Population control is fundamental and essential as to avoid long term damage to the environment as a consequence of acid rain, green house effect and possible Global Warming, and the threat to the ozone layer.