Overpopulation and development

1
Overpopulation and development
2
Overpopulation

• The number of people in a region is greater than
  the ability of the land to support them
• Carrying capacity no. of people a region can
  support with its basic resources

3

• Optimum Population no of people in a region
  with high standard of living given regions level
  of development and natural resources at any time
• Under population no of people living in area
  cannot exploit fully the natural resources
• Inward migration improves SOL for all
• Ireland 1997-2007 labour shortages

4
Causes of overpopulation

1. High birth rates demand on basic resources
   increase ie. The Sahel
2. Migration people forced to leave areas puts new
   areas under pressure ie. Darfur in Sudan
3. Overuse of sources resources that the population
   depend on becoming overused leading to
   overpopulation ie. Cod banks in the north atlantic

5
Factors to increase carrying capacity
Factors How these factors work
1. Decreasing population Reduces demand for basic resources
2. Fertilisers Increase food supply and feed more people
3. New farming methods Feed more people
4. Irrigation Raises crop yields, more water
5. Better crops/ animals Feed more people
6. Land reclamation Provides new land for settlement and farming
6
Factors to decrease carrying capacity
Factors How these factors work
1. Population growth Raises demand for basic resources
2. Soil erosion Reduces food supply
3. Deforestation Reduces fuel supply/ increases soil erosion
4. Flooding Destroys living space and farmland
5. Overgrazing/ over cropping Damages soil and reduces food supply
6. Urbanisation Raises demand for resources/ reduces farmland
7. Climate change Makes land areas uninhabitable
7
Case study The Sahel

• An area stretching across northern Africa
• 5,0000km long and 300km wide
• a semiarid zone
• extends from Senegal (west) through Mauritania,
  Mali, Burkino Faso, Niger, Northern Nigeria,
  Sudan to Ethopia.

8
Case study

• Focus on Sudan
• Same size as France
• Barren land
• 33 of population live in 7 of land
• Capitol city Khartoum
• Stage 2

9
Factors contributing to overpopulation and
overuse of soils

• 1. Birth rate
• birth rate 33 per thousand
• death rate 10.28 per thousand
• Population 43million
• Infant mortality rates 81 per thousand
• ½ population under 18 HDR
• Led to a number of problems
• Overgrazing status of cattle
• Deforestation need of fuel, manure often used
  (no natural fertilizer in the soil)
• over cultivation use of cash crops to pay debt

10
Factors contributing to overpopulation and
overuse of soils

• 2. Migration and conflict
• Civil war and famine led to internal migration
• Since 2003 Darfur has become a human rights
  crisis region
• 120,000 fled to Chad or to area at the east of
  Sudan
• Suffering brain drain
• Influx of 1milliion from Ethiopia

11
Factors contributing to overpopulation and
overuse of soils

• 3. Environmental degradation
• Global warming increased temp and evaporation
• Droughts reduces food production
• Rainfall levels decreased by 30 over 20 yrs
  leading to drying of soil triggering erosion
• Wells drying up and droughts 1968-73, 1983-5, dug
  lower which lowers the water table
• Desertification caused by deforestation and
  drought cause the Sahara desert to spread
  southward by 10km a year

12
Unsustainable Farming Methods
CAUSE EFFECT
OVERGRAZING Cattle exceed carrying capacity Indication of wealth and importance GRASS CANNOT REGROW SOIL EROSION DESERTIFICTION
OVERCULTIVATION. FARMERS ARE FORCED TO GROW CROPS ON POOR LAND THE CONTINUAL USE OF THE SOIL LEADS TO LOSS OF SOIL STRUCTURE. THE SOIL IS EASILY BLOWN AWAY BY DESERT WINDS SOIL EROSION DESERTIFICATION
DEFORESTATION. TREES ARE REMOVED FOR FUEL AND TO CLEAR LAND FOR CROPS REDUCED TRANSPIRATION OF MOISTURE FROM PALNTS LEADS TO LESS RAINFALL ANIMAL MANURE USED AS FUEL INSTEAD OF WOOD. NO LONGER USED TO FERTILIZE THE GROUND REDUCED CROP COVER
13
Effects of overpopulation

• Socio-economic
• Soil degradation
• Cash crops on valuable land
• Increasing population
• Farmers more sedentary
• Refugees not self reliant
• Environmental
• Change in rainfall patterns
• Conflict over water

14
OVERPOPULATION AND INCOME

• Areas with highest birth rates and highest levels
  of population growth have the highest levels of
  poverty
• poorer countries have a higher birth rate
• Children are seen as economic assets
• In high income families children an economic
  liability - 50,000 to rear child 1-18yrs
• Education of women central to decline in birth
  rate
• UN Development Programme
• 1.3 billion live on less than .77 cent a day
• 800 million people do not get enough to eat
• 500 million are chronically malnourished

15
Impact of Income levels on development

• UN development programme 500 million
  malnourished
• Poor people larger families, economic asset
• High population density not sole indicator of
  poverty population
• High income families children an economic
  liability
• Education of women central to decline in birth
  rate

16
Income levels and development

• Kenya
• Pop 39.8m
• Density of 69km
• poor, mainly rural
• Stage 2
• Population growing rapidly (fertility rates high)
• 42 of pop 1-14age group
• Low incomes
• Women low social status
• Low quality education and health services
• Infrastructure poor
• Foreign investment weak
• Underemployment and unemployment high
• Low pop density but is overpopulated

• South Korea
• Pop 49m
• Density of 487km
• Successful economy, exports orientated
• Stage 4
• Population growing slowly
• Economy developed per capita income improved
• High quality education and health
• Densely populated
• Modern lifestyle and a good standard of living
• Unemployment remains low
• High pop density but it is not overpopulated

17
Impact of technology on populationmedical
technology

• World pop doubled in 40yrs
• Medical research has developed vaccinations as
  preventative measures
• Improved access to family planning
• Vaccinations have been developed to cure/prevent
  infections ie. Measles etc
• Infant mortality rates decreased
• Some are cheap and administrated in primitive
  conditions by use of syringe
• Better education more women starting families
  later
• Rate of increase not as rapid as a result
• Geneline therapy promised to eliminate fatal
  human diseases

18
Impact of technology on populationagricultural
technologyIncrease in food supply leads to
longer life expectancy
Advance Results
1. Improved fertilisers Increased yields
2. New strains of plants Able to grow and thrive in strained conditions
3. Chemicals New pesticides and herbicides allow food to thrive
4. Glasshouses Able to grow plants in artificial conditions all year round
5. Machinery Harvesters, planters, pickers gather more crops increasing yields
6. Selective animal breeding Increased meat and milk yields from each animal
7. Irrigation Brings formerly dry land into production
19
Ecological footprint and sustainability

• Ecological footprint Area of forrest land,
  agricultural land, recreational space etc
  required by a person to live
• Several hectares per person in the developed
  world V less than 1 hectare in developing world
• 2006 Switzerland 5.6 hectares
• but China 1.8 hectares
• Sustainability is based on the recognition that
  when a resource is consumed faster that it is
  produced or renewed the source runs out
• Technology can make a positive difference
• Developed world needs to change buy food
  locally, reduce air travel etc

20
GM foods The Green Revolution

• Increase in food production, technology
  research, 1960s
• Modified for desired traits e.g. Salt tolerance
• Disadvantages
• Expensive products and equipment
• Oil derived fertilisers- non renewable resource
• Genetic diversity reduced

21
Population growth and developed countries

• Developed countries are in stage 4 and 5
• Agricultural and industrial revolution caused
  economic growth in Europe
• Tax revenue allowed for continued investment in
  health and education
• Increase in life expectancy and lower birth rate
• Today high standards of living , aging population
  and high GNP

22
Population growth and developing countries

• Stage 2 many countries experiencing high
  population growth
• 30 under the age of 14yrs
• Increase need of food, infrastructure, education
  and services
• Civil wars, corrupts leadership and MNCs
• Not experiencing economic development in the same
  way that Europe did as due to unfair trading
  systems
• Migration to shanty towns cities pop can double
  in 15yrs
• Low incomes cannot afford to invest in education
  and health
• Large families needed to provide economic
  security
• Very young age dependency ratio
• Population growth increase in rural-urban
  migration
• Brain drain leave to find well paid work else
  where
• Loss slows down economic progress in country of
  origin

23
Over population impacts on society and culture in
Bangladesh

• Poor country
• Primary economic activity agriculture
• Population 158 million
• 28 urban areas
• 1100 per km squared
• Causes of over population
• Risk of flooding
• Low lying delta
• Annual monsoon season, typhoons
• 1m of water floods 20 of Bangladesh land
• Sterilises agri land and contanimates water
• Infection typhoid and cholera

24

• Social Factors
• Stage 3
• Birth Rates declining with family planning
• 4 births per mother in 1990 but only 2.6 in 2011
• Muslim Marry young, desire for sons
• Adult literacy rate only 47

25
Effects of overpopulation Bangladesh

• Migration
• Land scarce
• Rural to urban migration, lack skills, live in
  shanty towns
• Overcrowding
• Both rural and urban areas
• Shanty towns high mortality rates
• Domestic servants- remittance