1. Topic 8: Human Systems and Resource Use
Topic 8.1: Human Population Dynamics
Starter: Match the key terms to the definitions
Key Term
Definition
Crude Birth Rate (CBR)
The rate of human growth expressed as a percentage change per year
Crude Death Rate (CDR)
The number of births per thousand individuals in a population per year
Natural Increase Rate (NIR)
The average number of children each woman has over her lifetime
Doubling Time (DT)
The number of death per thousand individuals in a population per year.
Total Fertility Rate (TFR)
The time in years that it takes for the population to double in size.

2. Human Population Statistics
Demographics – the study of the dynamics of population change. (Basically how and why populations change over time) population/ - see every person in the world - every Facebook profile picture growth/ - lots of data on human growth

3. Until recently human population has followed an exponential curve.
Growth is proportional to population size:
as population increases so does growth rate.

4. Growth is slowing, however population still predicted to double in the next 100 years

5. Its very difficult to predict future growth, all our predictions are based on past and current trends.
Human behaviour is very unpredictable making mathematical models unreliable.
High – CDR falls rapidly, CBR will fall very slowly
Middle – Both CDR and CBR fall, CDR slightly faster than CBR
Low – CDR will not fall (no cures to major diseases), and CBR falls

6. https://www. youtube. com/wat ch
ch?v=FACK2knC08E DON'T PANIC — Hans Rosling showing the facts about population 1 hr

7. Measuring population changes
We have definitions for CBR, CDR, NIR, DT and TFR. But you need to be able to calculate them.
Using the table I have given you fill in the missing boxes.
NIR = (Crude birth rate – crude death rate)/10
Migration is ignored
An NIR of 1% will make a population double in size in 70 years: therefore doubling time for a population is 70/NIR
Describe and explain the differences in the data for the three regions Asia, India and Africa.

8. Human population growth and resources
More people require more resources
More people produce more waste
People want to improve their standard of living
So the more people there are the greater the impact.
These 4 facts make a very complex issue (too?) simple.
One human in one country could have a hugely different impact to another human in an another country.
MEDC/LEDC
Urban/rural
Age

9. Food shortage
Our populations are growing quicker than food production.
Malthusian and Boserup’s theories

10. Malthusian Theory - 1798 Food is the main limit to population growth
Populaion growth is exponential e.g. 2, 4, 8, 16
Food production is growing arithmetically e.g. 2, 4, 6, 8, 10
At the point where population is larger than food resources a “catastrophe” will occur.
This could be mass soil degradation, mass famine, war etc.

11. Boserup’s Theory
Populaion growth is exponential e.g. 2, 4, 8, 16
However, when pressure becomes high enough food production will increase due to technological advances
This is an optimistic, technocentric view.
“Necessity is the mother of invention”
Based on research into land use systems.

12. Limitations Malthusian Theory Boserep’s Theory Too simplistic
Not all areas are as suitable for technological developments, land may simply be running at maximum output
Other factors (not just food) control population growth
Assumes technological advancements are possible
Only the poor go hungry
Food is not evenly distributed
Does not account for technological advances
Assumes “closed” populations: does not account for movement of people making it very difficult to actually test these theories. Migration usually occurs before pressure leads to disasters or technological advances.

13. Application of these theories
Evidence to support both theories.
Both can be right because Malthus refers to the environmental limitations and Boserup refers to cultural and technological issues.

14. Discuss: Why do people have large families
Discuss: Why do people have large families? Why are families getting smaller?
In the many parts of the world, families are getting smaller, (ex: Grandma was 1 of 9, but you are 1 of 2)
Although this trend is happening world wide, many countries still have large families. Why?

15. Why do people have large families?
High infant and childhood mortality
Security in old age
Children are an economic asset (particularly in agricultural societies)
Status of women – “baby factories”
Unavailability of contraceptives
Why are families getting smaller?
Provide education
Improved health
Make contraceptives
Enhance income – particularly small scale projects such as microlending
Improve resource management

16. Population pyramids – The Basics
Show a cross section of a population at a particular moment.
Divided into genders and age groups

17. Interpreting a population pyramid

19. Demographic Transition Model – How demographics change over time

22. (a) Award [2 max] for comparisons and calculations of % growth Ethiopia = × 100 = 161% (allow 160% to 161%); Austria = × 100 = –9% (negative value) (allow –8% to –9%); Ethiopia shows a high/positive growth rate whereas Austria shows a low/negative growth rate;
Award [2 max] for differences in pyramids (shown in diagram or described in words) Ethiopian pyramid is shorter than Austrian pyramid (because of higher life expectancy in Austria); Ethiopian pyramid is triangular and Austrian pyramid is parallel-sided; Ethiopian pyramid widens towards base but Austrian pyramid becomes narrower at base; Larger overall area for Ethiopian pyramid/smaller overall area for Austrian pyramid. Award [2 max] for position in demographic transition model (shown on diagram or described in words) Ethiopia likely to be in stage 2 (or 3) Ethiopia is at an early stage where death rates are falling below birth rates; whereas Austria likely to be at the end of stage 4 (or in a possible stage 5)/Austria is at a very late stage with birth rates falling below death rates; 7 max
Award [1 mark] for clear and appropriate sketches of pyramids and/or demographic transition model.

24. Population pyramids at each stage
Note: Dependence ratio is the number of economically active individuals against the number of economically dependant individuals.
People younger than 15 and over 65 generally are generally dependant on those between the ages of 15 and 65.

25. Problems and controversies with the DTM
Model only based on several industrialised countries
5th stage only added recently
Death rate has not fallen as rapidly in many places, large influx to cities has lead to slums with poor sanitation, therefore death rate still high.
AIDs related diseases may also be responsible.
The fall in birth rate assumes contraception is available. Some religions do not allow this. It also assumes women receive more education and rights.
Arab states in particular are highly developed but still have poor women's rights and therefore still have high birth rates.
Some countries have rapidly advanced through the stages and not all parts of the country have kept up.
This is a Eurocentric model and assumes all countries become industrialised. This is not always the case.

26. National and international policies influence human population growth
Policies that reduce population growth rate:
Pension schemes reduce parents reliance on their children for care when they are elderly.
Taxes and poor job security can lead to a decision to have a smaller family.
Any policy that stimulates economic growth usually leads to increased education and therefore knowledge of birth control.
Urbanisation limits physical space to have large family.
Policies directed at educating and liberating women.

27. National and international policies influence human population growth
Policies that increase population growth rate:
Agricultural development, improved public health and sanitation etc. may lower CDR and stimulate rapid growth without lowering fertility (stage 2 of DTM)
Lowering income tax or giving incentives and free education may increase CBR. E.g. Australian baby bonus
Encourage immigration, particularly of workers. Especially if immigration is from less developed countries.
Germany’s population was decreasing, will the large influx of refugees change this?

28. Case study:
Choose a country and look at its population policies. Also think about the cultural, historical, religion, social, political and economic factors that have influenced its population growth. Some good examples: India, China, Iran, Colombia, Brazil, Singapore. Some countries have tried to reduce growth, others increase it.