Population Distribution and Density

• The issues surrounding population are intricate, and the impact of population growth on the future is a significant concern for humanity
• The need to understand where people live and why is essential

Population Distribution and Density

• Many regions have sparse populations due to extreme climates, poor soil, mountainous terrain, or remoteness
• Only a third of Earth's land surface is inhabited
• Of that, only a third is inhabited by more than 20 people per square kilometer
• Deeper colors or more dots on a population density map indicates a higher concentration of people per square kilometer
• Lightly colored areas indicate sparsely populated regions
• Physical factors like land relief, soil quality, climate, vegetation, water access, and accessibility all affect population distribution
• Human factors include economic, political, and technological influences

Measuring Population Growth

• Population trends are determined by examining Crude birth rate and Crude death rate
• Crude birth rate is the number of live births per 1,000 people per year
• Crude death rate is the total deaths per 1,000 people per year
• Natural increase or decrease is the difference between crude birth and death rates
• Population change is also affected if people are Immigrating or Emigrating
• Life expectancy is the average number of years a person is expected to live in a region at birth
• World life expectancy in 2017 was 71 years, compared to 52 years in 1969
• Fertility rate is the average number of children a woman gives birth to in her lifetime
• Infant mortality rate measures the number of infants who die before age one
• Child mortality rate measures the number of children who die before age five
• Data collection methods vary by country, leading to potential inaccuracies in population representation

Population Trends and Patterns

• Population data reveals trends, patterns, and comparisons between countries
• Doubling time shows how quickly a population is growing
• The highest annual growth rate occurred between 1950 and 1990, peaking at 2.1% around 1970
• More people giving birth, rather than an increased global fertility rate, is why world population still grows, even though annual growth rate has declined
• World population doubled in 125 years from 1803 and 1928
• The time to double again from 1975 took only 76 years

Demographic Transition Model (DTM)

• The Demographic Transition Model (DTM) illustrates how birth and death rates affect population growth
• Stage 1: High birth rate and high death rate, resulting in a stable population
• Stage 2: High birth rate but falling death rate, leading to population increase
• Stage 3: Declining birth rate while total population continues to increase
• Stage 4: Low birth and death rates, resulting in a high total population
• Stage 5: Death rate exceeds birth rate, causing population decline
• The DTM focuses on birth and death rates and does not include migration

Population Structure

• Population distribution that accounts for percentage of males and females is shown on an age sex pyramid
• On age-sex pyramids, males are shown on the left and females on the right
• Age is shown in five-year bands
• Ethiopia's broad base on a population pyramid indicates a high fertility rate
• The older population starts to decline at around 80 years, which indicates a low life expectancy.
• At each of the childhood age sections, the total population decreases, showing a high infant and child mortality rate
• A higher cultural preference for boys can be inferred if the population born of males exceeds females
• Studying population pyramids discern the factors that affect population in certain countries

Managing Population

• Youthful age groups are 0-15 years of age
• Elderly age groups are over 60 years of age
• Working age groups are People 15–59 years
• Governments and policymakers need to plan how to meet societal needs with regard to its population demographics

Migration

• Migration, along with births and deaths, is a factor that directly affects population growth
• Immigration is movement of people into a country
• Emigration is movement of people out of the country
• Internal migration is when a person moves within a country's border
• International migration is when a person is moving across borders
• Voluntary migration: when the person chooses to move
• Forced migration: when a person is obliged to move because their life is threatened or endangered
• Push factors are negative reasons which explain a person leaving their place of origin
• Pull factors are positive reasons that attract the person to move to the place of destination
• When large scales of people migrate there are significant impacts on both origin and destination
• Remittance: money sent home to the family to spend on education
• A large percentage of the world's displaced come from conflict, climate change and land grabbing
• An unprecedented 68.5 million people around the world have been forced from home
• 25.4 million refugees, over half of whom are under the age of 18
• 10 million stateless people who have been denied a nationality and access to basic rights
• Nearly 1 person is forcibly displaced every two seconds as a result of conflict or persecution
• Conflict between countries or civil war has been the primary cause of refugees
• Climate change examples include: Sub-Saharan Africa and The Pacific Islands
• Land grabbing examples include: Amazonian indigenous groups