1. Human Population Explosion

2. 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

3. It’s just like a explosion!!!!!
How quick is the population growing???
Rate of increase = births - deaths
Though birth rate remains constant or
has a slightly drop, but the death rate
drops rapidly.
The population has grown at an
ever-increasing rate!
It’s just like a explosion!!!!!

4. 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 number
of human may die.

5. Cause Of Overpopulation
Change in methods of food production?
Agricultural Revolution?
Industrial Revolution?
Progress in medicine?

6. The significant rise in population growth rate
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)

7. The Domino Effect of the development of humans
Industrial Revolution
Population increase
Agricultural Revolution
Food production increase

8. The other Domino Effect
Industrial Revolution
Population increase
Medical Revolution
Mortality rate drop
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

9. Problem posed by overpopulation
Social Problems
World Food Problem
Impact to Environment

10. 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.

11. 2. The World Food Problem
Which is the most serious social problem of the overpopulating
Political instability
Unfair trading policy
Uneven distributed food supply
Unbalanced population distribution
So much food is wasted
Deforestation inhibits food production
Natural disasters
Famine in less-
developed countries

12. The cause of world food problem
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.

13. 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
4. Unbalanced population distribution:
population of less-developed countries >>> population of well developed countries
consumption(well developed countries)>>>consumption(less-developed countries)

14. Wasteful eating habits of the people
5. So much food is wasted:
Wasteful eating habits of the people
6. Deforestation inhibits food production:
Soil erosion -> soil no longer fertile
Natural disasters:
Droughts, floods, pests
Slow-down of food production

15. 1.4million
Zambia
3.7million
Tanzania
2.1million
Somalia
801000
Mozambique
4.9million
Malawi
3.5 million
Kenya
> 10 million
Ethiopia
230,000
Djibouti
2 million
Burundi
Population at risk
Country
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

16. 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

17. 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.

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

19. 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.

20. Air Pollution -Carbon monoxide -Sulphur dioxide -Nitrogen dioxide -Hydrocarbons -Ozone -Particulates
Land Pollution
-Waste disposal
-pesticides
Water Pollution
Toxic chemical
Oil

21. Deforestation A large area of forest was pulled down by humans.
Lots of organisms lost their habitat.
Soil erosion
Desertification

22. 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?

23. 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

24. 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

25. 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.

26. 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.

27. 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 worsen Controlling the population is critical to saving the environment from hazards of pollution.

28. Population Control Policy
China : 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.

29. 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.