Population Growth and Regulation Environmental resistance limits population growth.
Population lesson 1 world population growth
-
Upload
siti-mutiah-ali-umar -
Category
Technology
-
view
3.680 -
download
2
description
Transcript of Population lesson 1 world population growth
POPULATION
World Populati
on Growth
1. The world population grew very slowly up until about 1900.
2. The population then exploded and increased rapidly and still continues today.
3. 1900 - the world population were 1.7 billion.
4. By 1950 - it had reached 2.5 billion. More than a 50 % increase in the last 50 years.
5. Between 1950 and 2000 the population grew to 6.2 billion.
4. By late 2011, it had reached 7 billion.
5. The near future Global population shows no sign of slowing down.
6. The world population has continued to grow because the birth rate has remained higher than the death rate
World Population
6. Most of the population growth - found in LEDCs such as China and India.
7. Africa’s population growth is large despite the Aids virus lowering life expectancy.
8. Most rich countries have stable populations (e.g. France and the USA)
9. While some others have declining populations (e.g. Russia).
Countries which are projected to have largest population growth:
(1) India 467 million projected population increase
(2) Nigeria 231 million
(3) Pakistan 101 million
(4) Tanzania 93 million
(5) United States 93 million
(6) DR Congo 83 million
(7) Ethiopia 62 million
(8) Philippines 62 million
(9) Uganda 61 million
(10) Kenya 56 million
The top countries in order of the expected increase in population between 2010 and 2050 are:
Trends in Global Population Growth
Natural Population Increase – when birth rate is higher than the death rates
A country’s population growth rate depends on:
Natural increase
Migration
Both these variables have positive and negative effects upon growth
Patterns of population growth1. Rates of population growth vary across the
world.
2. Although the world's total population is rising rapidly, not all countries are experiencing this growth.
3. In the UK, for example, population growth is slowing, while in Germany the population has started to decline.
3. MEDCs have low population growth rates, with low death rates and low birth rates.
4. LEDCs have high population growth rates. Both birth rates and death rates in LEDCs tend to be high. However, improving healthcare leads to death rates falling - while birth rates remain high.
Patterns of population growth
The table shows data in selected LEDC and MEDC countries. The figures are per 1,000 of the population per year
Patterns of population growth
5 In Bulgaria, the birth rate is 9/1,000 and death rate is 14/1,000.
Bulgaria has a declining population.
6 In South Africa, the birth rate is 25/1,000 and death rate is 15/1,000.
South Africa has an increasing population with a population growth rate of 1 %
Reasons for population growth:
The creation of modern economics system as a result of the agricultural & industrial revolution
The vast knowledge of medical has increased the rate of babies born and decreased death rate
Modern technology and communications have enable us to tackle and overcome the worst effects of floods, famine and other natural hazards
Problems of population growth:
1. Creates great demands on governments to provide for people
2. Increased pressure on the environment
3. Increased risk of famine and malnutrition
4. Threats to international security
1. Creates great demands on governments to provide for people
Rapid population growth aggravates poverty in developing countries
High ratio of dependent children for each working adult
High % income spend on immediate survival needs (food, clothes, housing..etc) leaving little money for investment in the economy, education, govt services or infrastructures
2. Increased pressure on the environment
The expansion of human activities – associated with the loss of habitat
Extinction of plants and animal species world wide
Loss of biological diversity leads to instability of ecological system esp those that are stressed by climate change
Water pollution leads to intolerable health conditions for people
On global basis, the emissions of greenhouse gases -CO2 are rising rather than falling
Endangered animals
3. Increased risk of famine and malnutrition
Water shortages – water tables on every continent are falling
Water is pumped out far greater than rainwater can replenish – e.g. India pumped water twice the rate of natural replenishment
Due to industrialisation – loss of agricultural land
Demand for more meat instead of grains
Great demands of food will certainly drive the price of food up
4. Threats to international security
The risk of high unemployment
Rise to severe political instability – threatens national & international security
Growth of refugee due to the combination problems of poverty & violence