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KENDRIYA VIDYALAYA BALLYGUNGE. Power Point P resentation by--- D.K.Pandit P GT Geography. The World Population. Distribution Growth. Density. Gist of the lesson. Patterns of population distribution in the world. Density of population.
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KENDRIYA VIDYALAYA BALLYGUNGE Power Point Presentation by--- D.K.Pandit PGT Geography
The World Population Distribution Growth Density
Gist of the lesson Patterns of population distribution in the world. Density of population. Factors influence 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
Patterns of population distribution in the world. 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.
Density of population Each unit of land has limited capacity to support people living on it. Hence, it is necessary to understand 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 Density of Population =Population/Area 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: Density=1,50,000/100= 1,500 person/sq. km
Factors influence the distribution of population Geographical Factors Availability of water: people prefer to live in areas where fresh water is easily available. It is because of this that river valleys are among the most densely populated areas of the world. Landforms: People prefer living on flat plains and gentle slopes. This is because such areas are favorable for the production of crops. Climate: An extreme climate such as very hot or cold deserts are uncomfortable for human habitation. Soils: Fertile soils are important for agricultural and allied activities.
Factors influence the distribution of population Economic factors i)Minerals-areas with mineral deposits attract industries. Mining and industrial activities generate employment. (ii)Urbanization: Cities offer better employment opportunities, educational and medical facilities, better means of transport and communication.
Factors influence the distribution of population 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.
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. • Components of Population Change • Birth rate- birth rate is expressed as number of live birth in a year per thousand of population • Death rate-death rate is expressed in term of number of death in a particular year per thousand of population . • 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.
Trends in population growth The population on the earth is more than six billion. It has grown to this size over centuries. In the early periods population of the world grew very slowly. It is only during the last few hundred years that population has increased at an alarming rate.
Spatial pattern of population change Population growth in different parts of the world can be compared. The growth of population is low in developed countries as compared to developing countries. There is negative correlation between economic development and population growth.
Impact of population change Population is desirable in a growing economy. However, population growth beyond a certain level leads to problems. Of these the depletion of resources is the most serious. 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.
Demographic transition Rural Agrarian Urban Industrial Demographical 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
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. Thomas Malthus in his theory (1793) stated that the number of people would increase faster than the food supply.