The world population distribution, density and growth

Class 12 Geography CBSE Curriculum NCERT textbook Volume 1 chapter 2

1. The World Population Distribution, Density and Growth L R ASHA PGT GEOGRAPHY KENDRIYA VIDYALAYA NO 1 AIR FORCE STATION TAMBARAM CHENNAI 600073

2. World POPULATION

3. Gist of the chapter General, Patterns Of Population Distribution In The World, Density Of Population, Factors Influencing The Distribution Of Population, Population Growth, Trends In Population Growth, Doubling Time Of World Population Spatial Pattern Of Population Change, Impact Of Population Change, Demographic Transition, Population Control Measures.

4. Population of world as on 08/06/2020 TOP 20 LARGEST COUNTRIES BY POPULATION (LIVE) 1 China1,438,993,303 2 India1,379,191,625 3 U.S.A.330,886,953 4 Indonesia273,350,190 5 Pakistan220,632,291 6 Brazil212,469,212 7 Nigeria205,827,694 8 Bangladesh164,591,078 9 Russia145,930,757 10 Mexico128,851,537

5. "World Population" 7.8 Billion (2020) The current world population is 7.8 billion as of June 2020  [ 1 ]  according to the most recent United Nations estimates elaborated by Worldometer . The term "World Population" refers to the human population (the total number of humans currently living) of the world.

6. World Population

7. Population distribution The population of the world is unevenly distributed. George B. Cressey said the population of Asia that “Asia has many places where people are few and few place where people are very many” is true about the pattern of population distribution of the world also. The term population distribution refers to the way people are spaced over the earth’s surface. Broadly, 90 per cent of the world population lives in about 10 per cent of its land area .

8. DENSITY OF POPULATION Each unit of land has limited capacity to support people living on it. the ratio between the numbers of people to the size of land. This ratio is the density of population. It is measured in persons per sq km Density of Population = Population/ Area persons per sq km For example, area of Region X is 100 sq km and the population is 1,50,000 persons. The density of population is calculated as: 1,50,000 /100 = 1,500 person/ sq km

9. Classification population density The densely populated parts of the world with more than 200 persons on every sq km. - the North -Eastern part of U.S.A., North-Western part of Europe, South, South-East and East Asia. Areas like near the North and South Poles, the hot and the cold deserts and high rainfall zones near the Equator have very low density of population. - are sparsely populated regions of the world with less than 01 person per sq km. The areas of medium density. - are 11 to 50 persons per sq km - Western China, Southern India in Asia, Norway, Sweden in Europe are some examples

10. FACTORS INFLUENCING THE DISTRIBUTION OF POPULATION Physical Factors High Density Low Density Relief (shape and height of land) Low land which is flat e.g. Ganges Valley in India High land that is mountainous e.g. Himalayas Resources Areas rich in resources (e.g. coal, oil, wood, fishing etc.) tend to densely populated e.g. Western Europe Areas with few resources tend to be sparsely populated e.g. The Sahara Climate Areas with temperate climates tend to be densely populated as there is enough rain and heat to grow crops e.g. UK Areas with extreme climates of hot and cold tend to be sparsely populated e.g. the Sahara Desert  

11. FACTORS INFLUENCING THE DISTRIBUTION OF POPULATION Human Factors High Density Low Density Political Countries with stable governments tend to have a high population density e.g. Singapore Unstable countries tend to have lower population densities as people migrate e.g. Afghanistan. Social & Cultural Groups of people want to live close to each other for security e.g. USA Other groups of people prefer to be isolated e.g. Scandinavians Economic Good job opportunities encourage high population densities, particularly in large cities in MEDCs and LEDCs around the world. Limited job opportunities cause some areas to be sparsely populated e.g. Amazon Rainforest

12. POPULATION GROWTH 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.

13. Some Basic Concepts of Population Growth Growth of Population : Change of population in particular area between two points of time is known as growth of population. For example, the population of India 1991 (84.63 crore) from population of 2001 (102.70 crore) then the growth of population (18.07 crores) in actual numbers. Growth Rate of Population : This is the change of population expressed in percentage. 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 : Births – Deaths + In Migration – Out Migration Positive Growth of Population: This happens when the birth rate is more than the death rate between two points of time or when people from other countries migrate permanently to a region. Negative Growth of Population: If the population decreases between two points of time it is known as negative growth of population. It occurs when the birth rate falls below the death rate or people migrate to other countries

14. 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 women. It is calculated as: CBR =Bi/P x 1000 , Here, CBR = Crude Birth Rate; Bi = live births during the year; P=Mid year population of t he area.

15. Components of 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. CDR is calculated CDR = D/P x 1000 – Here, CDR=Crude Death Rate; D= Number of deaths; P=Estimated mid-year population of that year.

16. Migration Human migration is the movement of people from one place to another with the intentions of settling, permanently or temporarily, at a new location (geographic region)

17. CONCEPTS OF MIGRATION 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. The place of origin shows a decrease in population while the population increases in the place of destination 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.

18. FACTORS AFFECTING MIGRATION The Push factors make the place of origin seem less attractive for reasons like unemployment, poor living conditions, political turmoil, unpleasant climate, natural disasters, epidemics and socio-economic backwardness. The Pull factors make the place of destination seem more attractive than the place of origin for reasons like better job opportunities and living conditions, peace and stability, security of life and property and pleasant climate .

19. TRENDS IN POPULATION GROWTH

20. TRENDS IN POPULATION GROWTH After the evolution and introduction of agriculture about 8,000 to 12,000 years ago, the size of population was small – roughly 8 million. In the first century A.D. it was below 300 million. The expanding world trade during the sixteenth and seventeenth century, set the stage for rapid population growth. Around 1750, at the dawn of the Industrial Revolution, the world population was 550 million. World population exploded in the eighteenth century after the Industrial Revolution. Technological advancement achieved so far helped in the reduction of birth rate and provided a stage for accelerated population growth.

21. DOUBLING TIME OF WORLD POPULATION The doubling time is time it takes for a population to double in size/value. It is applied to  population growth ,  which can be calculated directly from the growth rate. The world's current (overall as well as natural) growth rate is about 1.14 percent, representing a doubling time of 61 years. We can expect the world's population of 6.5 billion to become 13 billion by 2067 if current growth continues. While the number of births and deaths is always a factor, things like war, disease, immigration, and natural disasters can affect a population's growth rate. Since doubling time is based on a population's annual growth rate, it can also vary over time.  Niger. With 48 births and 10 deaths per 1,000 people each year, the rate of natural population growth for this west African nation stands at 3.8%, the highest in the world.

22. DOUBLING TIME OF WORLD POPULATION

23. DEMOGRAPHIC TRANSITION Demographic transition theory can be used to describe and predict the future population of any area. 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 cycle

24. the three-staged model of Demographic Transition Theory 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. Fertility remains high in the beginning of second stage but it declines with time. This is 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. In the last stage, both fertility and mortality decline considerably. The population is either stable or grows slowly. The population becomes urbanized, literate and has high technical knowhow and deliberately controls the family size. This shows that human beings are extremely flexible and are able to adjust their fertility. In the present day, different countries are at different stages of demographic transition.

25. POPULATION CONTROL MEASURES 10 Effective Ways to Control Population Development. Easy and Cheap availability of Contraceptives. Education. Eradicate Poverty. Women Empowerment. Spread Awareness. Providing Incentives. Legislative Actions. Medical Facilities. Delayed Marriages .

26. recapitulation What is Population? What is Population Distribution? What is Population Density? How to calculate the Population Density? What is Population Growth? What is Birth rate? What is Death Rate? What is Migration? What is Population Doubling Time? Mention any two measures to control population.

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