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Population distribution refers to how populations is distributed unevenly around
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the globe. Because of this varied distribution, different regions and
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countries have different population densities. Population density measures
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the average number of people per square kilometer. The population density in a
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given country can be calculated by dividing the population by the area of
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that country. For example is on 2014 Thailand had a population of 68.7
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million people spread over 513000 square kilometers.
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When you divide 68.7 million by 513
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thousand square kilometers you get a population density of one hundred and
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thirty three point eight people per square kilometer. Patterns of population
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density can be displayed on a map such as a choropleth map or a dot distribution map.
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For example this current plate map shows the population density on a
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global scale. You can see that for places with high population densities are
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mainly found in the northern hemisphere. As mentioned earlier, some regions are densely
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populated, while other regions are sparsely populated. For example, in
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Sichuan Province China, the Sichuan Basin in the east is said
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to be densely populated. The mountainous western regions of the
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province is sparsely populated. Factors that encourage high population densities
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include the following. Regions of low elevation tend to have milder climates
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which attracts the people. Regions low-lying fertile land are good for
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agriculture. For example the North China Plain which lies flood plains of the
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Yangtze and Yellow Rivers. Regions with a good supply of natural resources are rich in
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resources such as copper and fossil fuels. Coastal areas tend to have a
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higher population than inland areas. For instance the vast majority of
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Australians live with 100 kilometers of the coastline. There several reasons for this.
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Coastal areas have a much milder climate than inland areas.
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They have rich resources such as fisheries. Coastal areas were also for those areas reached by
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immigrants, when new countries like Australia, New Zealand and the Americas were first settled.
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Factors that tend to result in sparse population densities include regions
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with extreme climates. For example extremely hot dry regions such as the
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deserts of Western Australia or cold regions such as the polar regions.
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Regions with high elevation such as the Qinghai-Tibetan plateau. At high
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altitudes temperatures tend to be cooler and soils are thinner and less fertile.
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The rugged relief these regions also makes development very difficult. In addition to
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extreme climates, regions in the interior of continents also tend to have poor access.
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Regions with dense impenetrable jungles are also sparsely populated.