Natural vegetation also may be a deterrent to human settlement, with, for example, the great rain forests such as the Amazon being poorly suited for high population densities. Coastal areas are often more attractive to settlement: Around two thirds of the world's population lives within 500 kilometers of the sea. Lowland areas tend to attract settlement more readily, with more intensive farming and industrial and commercial development. This makes agriculture less productive, with additional problems created by difficulty of access and transport. Mountain soils are usually thin, and at high altitudes temperatures and the oxygen content of the air decrease rapidly. Thus, in Lapland there is only 1 person per square kilometer, and in the Gobi Desert only 1.4.Īltitude is also significant. Accordingly, large areas of the globe are empty. In very cold and very hot environments the range of crops that can be grown, if any, is limited, and this inhibits human survival. Although the physical environment does not play a straightforward deterministic role, extremes tend to discourage human settlement.
Population density per square kilometer on a global scale is related to a number of factors both in the physical environment and in society and the economy. The Environment, Society, and the Economy The stylized maps presented in Figure 1 show how population is distributed by country and region and the broad changes in relative sizes over time. Table 2 shows the ten most populous countries in the year 2000. The increased population concentration in the less developed world reflects the exceptionally rapid growth of population in those areas since the middle of the twentieth century and lower growth and in some cases stability, and more recently even decline, in the more developed countries. (the United States and Canada), and 0.5 percent in Oceania. Europe accounted for 12 percent of global population, with a further 8.6 percent in Latin America and the Caribbean, 5.2 percent in North America By the year 2000 approximately 74 percent of the world's population lived in Africa and Asia (excluding the Russian Federation) on only 40 percent of the world's land area. Table 1 shows the growth of the world population since 1950 and its changing distribution projected to 2050. Less than 10 percent of the world's population lives in the southern hemisphere, and 80 percent lives between 20 degrees and 60 degrees north latitude. Population distribution on a global scale is highly uneven, with the greater part of the world's population living in the northern hemisphere and in countries in the less developed world.
The Distribution of the World's Population More specialized density measures also may be defined, such as population per unit of cultivatable land. Population density provides a comparative measure of distribution with respect to a geographic area that usually is expressed as persons per square kilometer (or per square mile) of land. Population distribution refers to the way in which the members of a population or of a specified subgroup of a population (for example, defined by age, sex, or ethnic status) are dispersed physically in a specific area.
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