PATTERNS OF POPULATION DISTRIBUTION IN THE WORLD
- The term population distribution refers to the way people are spaced over the earth‘s surface.
- 90 per cent of the world population lives in about 10 per cent of its land area.
DENSITY OF POPULATION
- The ratio between the numbers of people to the size of land. This ratio is the density of population. It is usually measured in persons per sq km.
FACTORS INFLUENCING THE DISTRIBUTION OF POPULATION
(i) Availability of water: It is the most important factor for life. So, people prefer to live in areas where fresh water is easily available
(ii) Landforms: People prefer living on flat plains and gentle slopes. This is because such areas are favourable for the production of crops and to build roads and industries.
(iii) Climate: An extreme climate such as very hot or cold deserts are uncomfortable for human habitation. Areas with a comfortable climate, where there is not much seasonal variation attract more people. Areas with very heavy rainfall or extreme and harsh climates have low population. Mediterranean regions were inhabited from early periods in history due to their pleasant climate.
(iv) Soils: Fertile soils are important for agricultural and allied activities. Therefore, areas which have fertile loamy soils have more people living on them as these can support intensive agriculture.
(i) Minerals: Areas with mineral deposits attract industries. Mining and industrial activities generate employment. So, skilled and semi–skilled workers move to these areas and make them densely populated. Katanga Zambia copper belt in Africa is one such good example.
(ii) Urbanisation: Cities offer better employment opportunities, educational and medical facilities, better means of transport and communication. Good civic amenities and the attraction of city life draw people to the cities. It leads to rural to urban migration and cities grow in size. Mega cities of the world continue to attract large number of migrants every year.
(iii) Industrialisation: Industrial belts provide job opportunities and attract large numbers of people. These include not just factory workers but also transport operators, shopkeepers, bank employees, doctors, teachers and other service providers. The Kobe-Osaka region of Japan is thickly populated because of the presence of a number of industries.
Social and Cultural Factors
- Some places attract more people because they have religious or cultural significance. In the same way – people tend to move away from places where there is social and political unrest.
- The population growth or population change refers to the change in number of inhabitants of a territory during a specific period of time. This change may be positive as well as negative.
- It can be expressed either in terms of absolute numbers or in terms of percentage. Population change in an area is an important indicator of economic development, social upliftment and historical and cultural background of the region.
Natural Growth of Population:
- This is the population increased by difference between births and deaths in a particular region between two points of time.
- Natural Growth = Births – Deaths
Actual Growth of Population:
This = Births – Deaths + In Migration – Out Migration
Components of Population Change
- There are three components of population change – births, deaths and migration.
- The crude birth rate (CBR) is expressed as number of live births in a year per thousand of population. It is calculated as:
- Death rate plays an active role in population change.
- Crude Death Rate (CDR) is a simple method of measuring mortality of any area. CDR is expressed in terms of number of deaths in a particular year per thousand of population in a particular region.
- When people move from one place to another, the place they move from is called the Place of Origin and the place they move to is called the Place of Destination.
- Migration may be interpreted as a spontaneous effort to achieve a better balance between population and resources.
- Migration may be permanent, temporary or seasonal.
- It may take place from rural to rural areas, rural to urban areas, urban to urban areas and urban to rural areas.
- Immigration: Migrants who move into a new place are called Immigrants.
- Emigration: Migrants who move out of a place are called Emigrants.
DOUBLING TIME OF WORLD POPULATION
- It took more than a million years for the human population to attain the one billion mark. But it took only 12 years for it to rise from 5 billion to 6 billion.
- developed countries are taking more time to double their population as compared to developing countries. Most of the population growth is taking place in the developing world, where population is exploding.
SPATIAL PATTERN OF POPULATION CHANGE
- There is negative correlation between economic development and population growth.
- Although the annual rate of population change (1.4 per cent) seems to be low it is actually not so.
- This is because: When a small annual rate is applied to a very large population, it will lead to a large population change.
IMPACT OF POPULATION CHANGE
- A small increase in population is desirable in a growing economy.
- Depletion of resources is the most serious problem.
- Population decline is also a matter of concern. It indicates that resources that had supported a population earlier are now insufficient to maintain the population.
- The deadly HIV/AIDS epidemics in Africa and some parts of the Commonwealth of Independent States (CIS) and Asia have pushed up death rates and reduced average life expectancy. This has slowed down population growth.
- The theory tells us that population of any region changes from high births and high deaths to low births and low deaths as society progresses from rural agrarian and illiterate to urban industrial and literate society.
- These changes occur in stages which are collectively known as the demographic
Three-staged model of Demographic T ransition Theory:
1. The first stage
- has high fertility and high mortality because people reproduce more to compensate for the deaths due to epidemics and variable food supply.
- The population growth is slow and most of the people are engaged in agriculture where large families are an asset.
- Life expectancy is low, people are mostly illiterate and have low levels of technology. Two hundred years ago all the countries of the world were in this stage.
2. Second stage
- Fertility remains high in the beginning of but it declines with time. This is‘2 accompanied by reduced mortality rate.
- Improvements in sanitation and health conditions lead to decline in mortality. Because of this gap the net addition to population is high.
3. Last stage
- both fertility and mortality decline considerably.
- The population is either stable or grows slowly.
- The population becomes urbanised, literate and has high technical know- how and deliberately controls the family size.
POPULATION CONTROL MEASURES
- Family planning is the spacing or preventing the birth of children. Access to family planning services is a significant factor in limiting population growth and improving women‘s health. Propaganda, free availability of contraceptives and tax disincentives for large families are some of the measures which can help population control.
- Thomas Malthus in his theory (1793) stated that the number of people would increase faster than the food supply.
- Any further increase would result in a population crash caused by famine, disease and war.
- The preventive checks are better than the physical checks. For the sustainability of our resources.