World Population, Distribution and Growth | Geography for UPSC CSE PDF Download

World Population,Distribution and Growth
• The earliest modern censuses were organised in Scandinavia—in Sweden in 1748, and in Norway and Denmark in 1769. 
• The first ce-nsus of the USA was held in 1790 and of England in 1801.
• In India it was not held until 1872.
• In China, the first census was not held until as late as 1953, when almost one fifth of the world’s population was brought into official statistics at a single stroke.
• In the U.K., individuals are recorded according to the place where they are found at the time of census, whereas in the USA individuals are recorded according to their usual place of residence. This is also followed in India.

Long Range World Population Projections
• The Department of International Economic and Social Affairs has brought about the Long-Range World Population Projections for two centuries i.e. from 1950-2150.
• Such projections, 160 years into the future, illustrate the evolution of population size and its characteristics under possible—and very hypothetical —scenarios of future levels of fertility and morality.
• The long-range projections extend the 1990 revision of the United Nations global population estimates and projections for an additional 125 years.

Age Structure
• By the year 2150 the median age of the population will have risen to this extension, in 2150 there will be one third more old people, aged over 65 or over, than children under age 15.
• In 2150, 18% of the world’s population will be under age 15, having declined from 32% in 1990 and 21% in 2050.
• The population of children less than 15 years old, which nearly doubled between 1950 and 1990, will only increase by 20% between 1990 and 2050, and is projected to not increase at all thereafter.
• At 2150, the percentage of the population aged 65 or over will have reached 24%, having risen significantly from 6% in 1990 and 14% in 2050.
• The population aged 80 or over, is projected to be multiplied by 5.7 between 1990 and 2050, and by another 3.5 between 2050 and 2150.

World Distribution of Population
• Population growth was very fast during the period 1950-90 with an annual increase of 1.9% resulting in a multiplication by 2.1 of the initial population to 5.3 billion.
• The growth of the world population in projected in the medium fertility extension to slow gradually, thereafter, with increase of 80% between the years 1990 and 2050 (to 10 billion), 12% between 2050 and 2100 (to 11.5 billion). In this extension, the population of world will ultimately reach 11.6 billion before stabilising.
• More than 90% of the world’s population is found in the northern hemisphere and over 85% in the Old World (Eurasia). This uneven distribution, caused by various factors will be analysed mainly in 3 type of concentration.
• Three Primary concentration of outstandingly high population density (over 100 persons per square kilometre) are evident on a world scale; namely (1) South-East Asia, (2) Europe and (3) North Eastern America. 
• These three regions alone account for 70% of the total world population.
•  In South east Asia more than 50% of the world’s population live on as little as 10% of the world’s land area.
•  In Europe 11% of the world’s population occupy less than 5% of the land area; while a further 4% occupy the Atlantic fringe of North America.
•  Various Secondary concentrations include California, eastern Brazil, the River Plate lowlands, North and South Africa and South Eastern Australia.
•  These secondary concentrations account for a population of about 5% of the world total.
•  The Tertiary concentrations often assume the form of ‘Knots’, such as the population clusters of the high basins of Mexico or strings such as the Nile Valley.

Ecumene and Nonecumene
•  Ecumene was a word used by the ancient Greeks to signify the inhabited portion of the earth’s surface, thus distinguishing it from the remainder which was uninhabited.
•  The term was revived by German geographers in the early 19th century and has been subjected to slightly differing interpretation.

 

The term Nonecumene is used to refer to the uninhabited, intermittently inhabited or very sparsely inhabited areas of the earth’s surface.

It has been estimated that approx. 60% of the earth’s land surface may be classified as ecumene and 40% as non-ecumene.

Influence on Population Distribution
• Physical Influences—Altitude, latitude, relief, climate, soils vegetation, minerals and energy resources.

Economic, Social and Political Influences
• In the present time, with increasing government control over economic activity, political influences have emerged as a significant factor affecting population patterns.
• In communist countries, population may be directed to areas of social or economic need, while in the western world various inducements may be offered to encourage or assist migration to new towns, development areas or simply away from overcrowded conurbations.
• Political events have also been responsible throughout history for mass migrations of population. The Post-war movement of refugees in to West Germany or the enforced expulsions of Asians from Uganda in 1972 provide examples of such a process.
• Historical processes also play an important role in contemporary population patterns. The duration of settlement in any area is of fundamental importance. 
• The relatively recent settlement of Australia is a basic reason for its low population density (2 person/km2), while then high density of India (267 persons/km2) may be partly explained in terms of its long history of civilisation and occupancy.

The World Pattern of Fertility
• In 1985 crude birth rate for the various nations of the world ranged from 9.6% (West Germany) to 55.1% (Kenya).
• The highest levels of fertility, with crude birth rates in excess of 40%, are experienced in most parts of Latin America, Africa, the Indian Sub-Continent and South east Asia.
• Relatively low fertility, with crude birth rates of less than 20%, is typical of the developed countries of Europe, North America, Oceania, former USSR and Japan. “These facts have led certain writers to suggest that a decline in fertility is an inevitable corollary of economic and social advancement”.

Population Composition
• The term ‘Population Composition’ is generally taken to include those characteristics of population for which quantitative data, especially census data, are available.
Age Structure
• The age structure of a population means, the number of males and females in each age group—is an expression of the processes of fertility, mortality and migration as they have operated during the life time of the oldest member of population.
Age groups
    • Children (0-14 or 0-19 years)
    • Adults (15-59 or 15-64, 20-59 or 20-64) and
    • Aged (60 and over or 65 and over).
• Examination of age-group statistics for different parts of the world shows that the proportion of adult population is the least variable of the three groups.
• The chief regional differences lie in the proportions of children and old people. On the basis of these variations Three types of Age Structure have been identified:
• The West European type, with less than 30% children and about 15% age population.
• The United States type, with 35-40% children and about 10% aged;
• The Brazilian type, with 45-55% children and only 4-8% aged population. Most of the developing countries fall in this category.
• The proportion of adults is lowest in the Brazilian type of structure, in some cases only 40% of the total population. Under these circumstances economic progress is difficult.
• The ‘old-age index’ is simply the number of aged people as a percentage of the adult population.
• The ‘dependency ratio’ is the combined total of children and aged population as a percentage of the adult population.

Age Pyramid
• A more detailed picture of age structure than is possible with either age groups or age indices may be obtained by the construction of an age Pyramid.
• Each age group of population is represented by a horizontal bar, the length of which is proportional to the percentages of males and females in that age group. Males are arranged to the left and females to the right of a vertical axis, which is divided either into single years or internal of 5 years.
• A ‘Stationary Population’, with unchanging fertility and mortality rates over a long period of time, produces a ‘regularly—tapering Pyramid’.
• A ‘Progressive population’, with an increasing birth rate and high mortality, produces a ‘wide-based’ and ‘rapidly tapering Pyramid’.
• A ‘regressive population’, with a declining birth rate and low mortality, produces a ‘narrow based Pyramid’.

Sex Composition
• The ratio of the two sexes in a population is normally expressed as the number of males per 100 or 1,000 females, or vice-versa.
• In the UK in 1986, 105 males were born for every 100 females.
• In developing countries infant mortality is markedly higher among males than females.
• The sex-ratio of any area will be greatly influenced by the effects of migration as well as the preponderance of male births and the differential mortality rates of the two sexes.
• At present, areas with the greatest surplus of males are the pioneer fringes of settlement such as Alaska and the Northern Territory of Australia, both of which have 135 men for every 100 women.
• Indian towns have an unusually high proportions of males; in Calcutta, for example, there are 175 men for every 100 women. In economically advanced nation the converse is true.

New Growth Trends
• The world’s population surpassed 5 billion in the middle of 1987 and is projected to grow to 6 billion just before the turn of the century.
• In the previous 13 years, it grew from 4 to 5 billion. The quarter century from 1975 to 2000 will have witnessed the greatest absolute expansion of the global population in such a short time.
• From 1980 to 1985 the annual rate of population growth was 1.7 per cent, compared with the peak rate of 2.0 per cent in the period from 1965 to 1970. It is expected to continue to decline slowly in the future. 
• Only in the next century, however, will there be a significant decline in the size of the net annual increments to the world total.
• There was a clear dichotomy in the 1960s between slow growth of population in the developed countries (the average annual rate was 1.1 per cent) and rapid growth in the developing countries (the average annual rate was about 2.5 per cent).
• The major developing regions showed little diversity, ranging from 2.4 per cent in Asia (excluding Japan) to 2.7 per cent in Latin America.
• Since the 1960s, however, the rates of population increase have become more diverse among the developing regions and their constituent countries, and the divergence is expected to increase in the 1990s.
• Population growth in Africa began to accelerate in the 1950s and continued to do so through the 1980s, while in most of the other developing regions it began to decelerate in the 1970s.
• The drop in the growth rate was particularly notable in China and the Asian planned economies; the drop is expected to continue in the 1990s, falling to little more than half the rate of the 1960s.
• Projected population growth rates for the 1990s are now about 3 per cent in Africa and Western Asia, 2 per cent in South and East Asia (excluding Japan and the Asian planned economies), 1.9 per cent in Latin America, and 1.3 per cent in China together with the Asian planned economies.
• The growth rate in the developed countries as a whole has fallen to 0.6 per cent in the 1980s and is projected to be only 0.5 per cent in the 1990s (0.8 per cent or less in North America and Eastern Europe and 0.3 to 0.5 per cent in the European market economies and Japan).
• The shift in the regional shares of global population is dominated by the growth of developing Africa and West Asia. Their combined share was 10 per cent in 2000.
• In contrast, the proportion of world population accounted for by the developed countries declined from 31.4 per cent in 1960 to 25.8 per cent in 1980, and is projected to be only 20.6 per cent in 2000.
• Population growth in the least developed countries has accelerated from an average rate of 2.4 per cent in the 1960s to 2.6 per cent in the 1980s. This is in contrast to a dramatic drop in China together with the Asian planned economies, from 2.4 per cent to 1.3 per cent, and a slight decline in the other developing countries as a whole.
• The difference is expected to be even greater in the 1990s—2.9 per cent in the least developed countries versus 1.3 per cent in China and the Asian planned economies and 2.3 per cent in the developing countries as a whole.

Mortality and life expectancy
• In the past decade, there have been decreases in infant mortality rates in nearly all countries, but more than one quarter, representing 29 per cent of world population, still have rates above 100 per 1,000 live births.
• Between 1985 and 1990, the average in the least developed countries is estimated at 123 per 1,000. In Africa as a whole it is 106, while the average in the developed countries (excluding South Africa) is about 15.
• Low mortality levels have also been achieved in some low-income countries where Governments are committed to reducing mortality; China, Cuba, Sri Lanka, and the state of Kerala in India are well-known examples, as is Costa Rica among middle-income countries.
• In the developed countries, life expectancy at birth has increased from 66 years in the early 1950s to 73 years in the late 1980s, while in the developing countries as a whole (including China), it has increased from 41 to 60.
• There was a dramatic increase in China, from 41 years in the early 1950s to 69 in the late 1980s; in Africa, it increased from 35 years to 49.
• The average life expectancy in the least developed countries in the period from 1985 to 1990 is also about 49 years.
• Life expectancy at birth is generally several years longer for women than for men, especially in the developed countries: 77 years for women versus 70 years for men in the late 1980.
• In the developing countries (including China), it is about 61 years for women and 59 years for men.
 

Ageing of populations
• Recent demographic trends suggest that from 1985 to 2000 the populations of both the developed and the developing regions will grow older. This is so in the sense that the median age and the proportion of elderly (60 and over) will increase.
• Between 1985 and 2000, the median age is projected to increase by 3.8 years in the developed regions and by 2.8 years in the developing regions as a whole.
• The world’s elderly population will grow by 2.45 per cent annually between 1985 and 2000, compared with 1.68 per cent annually for the total population. 
• The annual rate of growth of the number of elderly in the developing countries will be about 3 per cent, almost twice as high as in the developed countries. Nonetheless, the share of the elderly in the total population will not increase very much between 1985 and 2000.
•  In the developed countries, it will rise from 16 to 19 per cent; in the developing countries, from 7 to 8 percent (in Africa it will remain at 5 per cent). For the world as a whole, it will rise from 9 to 10 per cent.
•  For the world as a whole, the old-age dependency ratio (the ratio of those over 65 to those between the age of 15 and 64) will not change much between 1985 and 2000, rising from 10 to 11 per cent.

Population Distribution
 People’s Republic of China
•  China has the largest population in the world, but its average population in only about 75 PPSK (People Per Square Kilometer).
•  About 3/4th of China’s population is concentrated in only 15% of the land area.
•  The most densely settled region is in the east, while the western half of the country is still underpopulated.
•  Only about 1/6th of the population lives in towns in China.
•  Moderate densities are also found in the more favoured areas of the generally negative western Provinces.
•  In the interior Provinces of Siakiang, Gansu (Kansu), Tsinghai, Tibet and Inner Mongolia, where densities are generally less than 1 PPSK, physical factors such as a cold continental climate, aridity, high altitude and in accessibility have militated against intensive agriculture. 
•  The best form of land use is some form of herding. This extensive type of agriculture is practised by the Tibetans, Vighurs, Kazaks, Mongols and Kirghiz who inhabit the area but does not support large numbers of people.

Canada
•  Over 90% of its population live in a narrow belt not more than 320 km wide, immediately north of the US border, leaving the vast Northlands practically uninhabited.
•  Within the settled belt, the Western Coast, the Prairies and the Maritime Provinces are only moderately peopled while the St. Lawrence lowlands are more densely populated.
•  The Northlands do have some physical advantages, such as rich mineral resources, Coniferous forests and swift flowing rivers for the generation of HEP, but none of these need a large or permanently settled population for their exploitation. 
•  The only permanent inhabitants of the regions are Eskimos and certain Indian tribes.
•  The eastern seaboard was then first area settled by European immigrants. As the longest-settled part of the country it has the best social amenities.
•  Its nearness to Europe allows traditional links with Britain and France to be maintained as well as promoting trade and industry.
•  Another reason for the concentration of settlement in the South-east of the country is the promixity of the USA’s industrial belt. 
•  This has encouraged investment and therefore industrial development has led to a greater density of population, especially in and around the industrial centres of Toronto, Kingston, Montreal and Quebec.
•  The population of Canada is descended mainly from immigrants; about half from British and a third from French stock. 
•  While the English speaking Canadians are found throughout the country, the French are concentrated in Quebec and Eastern Ontario.

Peninsular Malaysia
•  In the North are the wide padilands of Kedah and Perlis, while further south are undulating lowlands which were found ideal for the growing of export crops, especially rubber and oil palm.
•  On the East Coast, however, the swampy coastal plain is narrower and gives way more rapidly to mountainous terrain, except in the north in a region around Kota Bharu and Kuala Trengganu where the lowlands are wider and support a high rural population growing rice, rubber and other crops.
•  The Western lowlands proved ideal for colonial Plantation development not only from a physical standpoint but also because of their proximity to the Strait of Malacca which has always been a major sea route.
•  Ports such as Malacca, Port Kelang and George Town provided outlets for the produce of the Western Coastlands. Population was expanded in the west by an influx of immigrant labourers for the plantations.

Nigeria
•  Nigeria has a very complicated pattern of population distribution, with three separate centres of dense population divided by regions of moderate or sparse settlement.
•  This pattern is partly governed by physical factors, since the area of least dense population, known as the ‘Middle Belt’ coincides with a region of poor soils, low rainfall and inadequate water supplies.
•  In the South-east the main cash crop is oil palm, in the South-west cocoa and some oil palm, and in the North the main crops are cotton and groundnuts.
    •  The Ibos are concentrated in the south east,
    •  the Yorubas are in the South West and,
    •  the Muslim Hausa people in the North.
•  In the North the main centres of population are large, isolated towns such as Kano and Sokoto which have traditionally served as termini on the caravan routes of the Sahara.
•  In the South-west, the towns are more concentrated, forming an area of dense population including Ibadan, Oshogbo and Oyo; the rural population is also fairly dense.
•  Lagos, the capital city, has grown rapidly by in-migration and is the centre of another densely settled region.

Japan
•  The most densely populated area are in the South and West. While the least populated regions are in the north.
•  The high densities, mainly over 1000 PPSK are found in then lowland coastal plains.
•  The mountainous backbone of the island of Honshu has poor agricultural potential, but climatic conditions are still good.
•  The northern island of Hokkaido has a cold, more extreme climate as well as mountains terrain and is they less densely populated.
•  The large industrial centres of Tokyo, Osaka, Yokohama, Nagoya Kyoto, Kobe have more than half the total population and the areas around them record densities of 8000 to 14000 PPSK.