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POPULATION. Social Studies Term 1. WORLD POPULATION. Currently, the world is inhabited by almost 7000 million people. The distribution of the world’s population is not equal. POPULATION DENSITY.
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POPULATION Social Studies Term 1
WORLD POPULATION • Currently, the world is inhabited by almost 7000 million people. • The distribution of the world’s population is not equal.
POPULATION DENSITY • In order to measure population distribution, we use population density: the relation between the number of inhabitants in a place and the size of area it occupies. • Population density is calculated by dividing the total number of inhabitants by the area of land occupied (in km2). The result is expressed in inhabitants/km2.
Population density varies from one place in the world to another: • The areas with higher population density are those with physical conditions (temperature climate, flatter land…) or human conditions (more job opportunities, stable political situation…) that make them attractive places to settle. • The areas with lower population density are those with physical conditions (very cold or very hot climate, mountainous…) or social conditions (lack of basic services such as education, health…) that make human settlement difficult. Some of these areas are demographic deserts. A demographic desert is an area with a population density of less than one inhabitant/km2.
NATURAL POPULATION CHANGES • Natural population change refers to increases and decreases in the population produced by biological factors (births and deaths).
NATALITYNatality is the number of people born over a year in a particular area. • The birth rate (BR) is calculated by dividing the number of births in an area over one year by the total population and multiplying the result by one thousand. The birth rate is expressed as a number per thousand (‰). • Less-developed countries have high birth rates because families need children to help with their economic activities. In other cases, high birth rates are a result of tradition (customs or beliefs transmitted from one generation to another). Developed countries have low birth rates. One of the reasons for this is the incorporation of women into employment outside the home.
MORTALITYMortality is the number of people who die over a year in a particular area. • The death rate (DR) is calculated by dividing the number of deaths in an area over one year by the total population and multiplying the result by one thousand. The death rate is expressed as a number per thousand (‰) • Since the end of the 20th century, improvements in diet, sanitation and health care have helped to reduce the death rate throughout the world. As a result, life expectancy has increased. Life expectancy is the average number of years that a person can be expected to live according to statistics. These improvements have also influenced the fall in the infant mortality rate (IMR: ratio of the number of deaths in the first year of life to the number of live births occurring in the same population during the same period). • Less-developed countries have a high death rate because of the lack of food and health care. Developed countries have a low death rate and life expectancy is high. However, the death rate is increasing slightly in these countries, due to the ageing of the population.
Natural increase is the difference between the number of births and the number of deaths in a population • If the number of births is greater than the number of deaths, natural increase is positive and the population rises. • If the number of deaths is greater than the number of births, natural increase is negative and the population falls. • The rate natural increase (RNI) is calculated by subtracting the death rate from the birth rate and expressing the result as a percentage (%) • Rate of natural increase = birth rate – death rate • RNI = BR - DR • The rate of natural increase is not the same all over the world. In less-developed countries, the rate of natural increase is high, while in developed countries, it is low or even negative.
POPULATION MOVEMENT • People move from one place to another. This movement can be regular or migratory.
Regular population movement • This movement takes place on a regular basis and does not involve a change of job or place of residence (place where a person normally lives). There are two main types: • Commuting: regular movement between a person’s place of residence and their place to work or study. • Leisure: movement related to free time, such as weekends away or holidays.
Migratory movement • This movement involves a change of job and place of residence. It can be internal (within the same country) or external (from one country to another).
Emigration refers to people leaving a particular area. Generally, emigrants leave their own region or country to find work and improve their living standard. In other cases, they are fleeing from wars or political conflicts. • Immigration refers to people arriving to live in a particular place. Immigration contributes to the rejuvenation of the recipient population. These countries or regions are usually politically stable and economically developed areas. • The migration balance is the difference between the number of persons having entered the • territory and the number of persons having left the territory in the course of the year. This concept is independent of nationality.
Negative effects of migration: decrease of the young workers, the population structure • changes (since normally men emigrates)and there is Brain drain (or human capital flight), that is • the large-scale emigration of a large group of individuals with technical skills or knowledge. It • leads to a decrease on the quality of workers. • Positive effects of migration: decrease of the unemployment rate and increase on the incomes
POPULATION STRUCTURE • Population can be classifies according to different criteria: • By sex: this refers to the ratio of men to women. Generally, more boys are born than girls but life expectancy is higher for women than for men. • By age: the population is usually divided into three groups: • Young people (0-14) • Adults (15-64) • And the elderly (65 and older) • By economic activity: we distinguish between the active population (people of working age, including the employed and unemployed population) and the inactive population (people who cannot work, such as minors and retired people, and people of working are who are not looking for a job).
A population pyramid is a graph that shows the structure of the population according to age and sex in a particular area. There are different types of population pyramid: young population, adult population and elderly population. The name depends on the predominant age group.
Young population • This population corresponds to a population that has a large proportion of young people and only a small proportion of elderly people. This is because the birth rate is high and life expectancy is low. This pyramid is common in underdeveloped countries.
Adult population • This pyramid has a large proportion of adults, just over 25% of young people and a low proportion of elderly people. This is due to an average birth rate and an increase in life expectancy. This pyramid is typical of developing countries.
Elderly population • This pyramid has a high proportion of elderly people and a low proportion of young people. This is the result of a very low birth rate and very high life expectancy. This pyramid is typical of developed countries.
POPULATION CHALLENGES • Estimates (approximate calculation) about the future of the population show that, in the year 2050, the world will have 9284 million inhabitants, of whom 8005 million will live in countries that are currently less developed and 1279 million in more developed countries. The demographic characteristics will vary considerably between the different countries in the world.
Less-developed countries: • The birth rate is very high while the death rate is low so the rate of natural increase is high and the population is young. • In some places, there are problems of overpopulation: the population increases at a faster rate than the available resources. So there is poverty and famine (widespread hunger), which forces many people to emigrate. • Governments of overpopulated countries sometimes try to reduce the birth rate by allowing couples to have only one child (for example, China) and by promoting birth control (family planning).
Developed countries: • The birth rate is low and the death rate tends to rise because there is a high proportion of elderly people. The rate of natural increase is very low, sometimes even negative. • These countries have ageing populations and have usually become the recipients of immigrants who, little by little, are rejuvenating the population pyramid. In these areas, birth is encouraged by offering financial or social benefits (maternity or paternity leave, state nurseries…)
Natural resources • Natural resources are basic resources such as water, wood… which nature provides for us. Some of these resources are used as raw materials (resource that industry transforms into finished or semi-finished products). Raw materials can be of vegetable origin (wood, fruit…), animal origin (eggs, leather, wool…) or mineral origin (coal, clay, iron…) • Some natural resources can be used as energy sources because they provide the force required to move machinery. Sources of energy can be of two kinds: • Non-renewable: these come from natural resources that may one day be used up (coal, oil, natural gas, uranium…) • Renewable: these are obtained from natural resources that are never used up (Solar energy, wind power, hydroelectric power…)
The distribution of resources • The Earth has sufficient resources for all population. However, its resources are not distributed equally, so in many areas people suffer from famine and don’t have access to basic services such as drinking water, health care… • In order to help solve these problems, the governments of some countries and NGOs (non-governmental organization) help the poorest countries by providing food and medicines, sending teachers and doctors…
Economic activity • Economics is the study of how to use resources to meet people’s needs. Economic activities produce economic assets. Economic assets can be of two kinds: • Goods: material objects, such as books and computers. • Services: activities carried out for the benefit of society such as transport, health and education.
Factors of production are different types of resource used in the production of goods and services. These can be: • Natural resources: resources found in nature, such as water, light, plants and animals. • Labour: human effort involved in the creation of products or provision of services. Labour is also called human resources. • Capital: means of production used to produce economic goods: money, machinery, vehicles, buildings…
Economic agents intervene in the economy. They can be classified as follows: • Family: a person or group of people (not necessarily related) who share a place of residence, buy products and receive services in exchange for money. • Company: an organization that produces economic goods and receives income in exchange. It has employees to whom it pays a salary. • State: it provides services (schools, hospitals, transport…) to citizens and collects taxes.
