Population Dynamics and Human Settlement
What you must know
Population dynamics covers birth rate, death rate, natural increase, migration and the resulting structure of a population. The demographic transition model shows stages from high birth and death rates to low ones. Population pyramids show age and sex structure: a wide base means high birth rates and a young population; a narrow top means short life expectancy or older population.
Concepts to master
Dependency ratio, infant mortality, life expectancy, fertility rate, population density and distribution. Settlement site (why here) versus situation (relationship to surroundings); dispersed, nucleated and linear patterns; urban hierarchy and sphere of influence.
Traps in questions
Do not confuse natural increase with total population growth; migration also matters. Do not read a pyramid upside down. When asked for reasons, separate economic, social and environmental causes.
Worked example
Dependency ratio = (under 15 + over 64) ÷ (15–64) × 100. If 30% are under 15, 10% over 64 and 60% are working age, ratio = (30 + 10) ÷ 60 × 100 ≈ 67 dependants per 100 workers. State the formula, substitute, and give the units.