The Human Population Chapter 9

Section 1: Studying Human Populations

Studying Human Populations Demography – the study of (ANY!!) population But usually only human populations Demographers (people who study populations) have two categories for countries - Developed and Non-Developed Developed – High incomes, slow population growth, lots of industry Can you name one? Non-Developed – Low incomes, fast population growth, agriculture based economy Studying Human Populations

Human Population Over Time Exponential Growth – Rapid increase in a population Due to better food production, medicine, hygeine Can we sustain this growth? Human Population Over Time

Forecasting Population Size Age Structure diagrams – can give a forecast of future issues Lots of children now, means a population increase in 10-15 years when those kids start having kids. Population Pyramids – Two sided – male and female Developed and Non-Developed countries have distinctive looking pyramids Forecasting Population Size

Survivorship Curves – the percentage of that population that will survive at any given age Type I – Few offspring, but they live a long time Type II – Equal chance of living or dying every day Type III – Most offspring die young with few surviving to older age

Fertility Rates: Number of babies born each year per 1000 women Total fertility rate: average number of children a woman will give birth to in her lifetime Replacement Level – The number of children a couple needs to have to replace themselves In developed countries this is 2.1 (why the .1?) Women are the biggest factor in controlling growth Education (jobs and childcare leads to not needing as many children) Birth Control Population can also change due to: Immigration – people moving in Emmigration - people moving out Death Rates are delining all over the world. Why? Life expectency – the average number of years someone will live Life expectency worldwide has risen to 67 years Factors affecting life expectency Contagious diseases, AIDS and tuberculosis

Demographic Transition Model Phase 1 – Agrarian - high birth AND death rates Phase 2 – Low death rates, high birth rate – POPULATION EXPLOSION Phase 3 – Birth rate is declining but population is very large Phase 4 – low birth AND death rates Demographic Transition Model

Time for a reading quiz That’s all for 9.1

Section 2: Changing Population Trends

Problems of Rapid Growth Infrastructure: basic facilities/services that support a community Public water, sewer, roads, hospitals, power plants Shortage of fuel wood Clean water, heat, and edible food come from a reliable heat source Expanding populations increase need/decrease availability of fuel wood Unsafe Water No sewers or water treatment plants Water sources (rivers) used for drinking, cooking, washing, AND sewage 1 billion people unsafe water worldwide/ 3 million died of water diseases Right here in US – Rio Grande river in Texas

Problems of Rapid Growth Land Impacts Arable Land –land where crops can grow More people need homes leads to less arable land Less arable lands leads to less food grown. Less food + more people = starvation Urbanization – people moving from rural to city Suburbs – sprawl, still taking up arable land Harsh environments –people live near resources - Egypt Problems of Rapid Growth

Not all countries are following the demographic transition model Some industry, but still low incomes High education, but low industry Least Developed Countries – a focus of world community and United Nations Still have high death rates, high birth rates, and little industry Diverse World

Population growth is slowing Countries working to slow population growth because of demands on environment and resources China – One Child Policy Family planning policies Financial Incentives Improving status of women Population growth is slowing We just hit 7 BILLION people

Time for a reading quiz That’s all for 9.2