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Population density (people per km²) of the world

Population density (people per km²) by country, 2006

Population density (people per km²) map of the world in 1994. In relation to the equator it is seen that the vast majority of the human population lives in the Northern Hemisphere.

Population density (people per km²) map of the world in 1994

Deserts around the world. Compare with maps above. See also this image for location of densely populated areas (cities) in various vegetation zones.

Population density (in agriculture: standing stock and standing crop) is a measurement of population per unit area or unit volume; it is a quantity of type number density. It is frequently applied to living organisms, and most of the time to humans. It is a key geographical term.^[1]

Biological population densities

Population density is population divided by total land area or water volume, as appropriate.^[1]

Low densities may cause an extinction vortex and lead to further reduced fertility. This is called the Allee effect after the scientist who identified it. Examples of the causes in low population densities include:^[2]

• Increased problems with locating sexual mates


• Increased inbreeding
  

Monaco in Southern Europe, currently holds the record for being the most densely populated nation in the world.

Mongolia is the least densely populated country in the world.

This population cartogram of the European Union (2007–2012) uses areas and colors to represent population.

For humans, population density is the number of people per unit of area, usually quoted per square kilometer or square mile (which may include or exclude, for example, areas of water or glaciers). Commonly this may be calculated for a county, city, country, another territory or the entire world.

The world's population is around 7,500,000,000^[3] and Earth's total area (including land and water) is 510,000,000 square kilometers (197,000,000 sq. mi.).^[4] Therefore, the worldwide human population density is around 7,500,000,000 ÷ 510,000,000 = 14.7 per km² (38 per sq. mi). If only the Earth's land area of 150,000,000 km² (58,000,000 sq. mi.) is taken into account, then human population density increases to 50 per km² (129 per sq. mile). This includes all continental and island land area, including Antarctica. If Antarctica is also excluded, then population density rises to over 55 people per km² (over 142 per sq. mile).^[1] However, over half^{[citation needed]} of the Earth's land mass consists of areas inhospitable to human habitation, such as deserts and high mountains, and population tends to cluster around seaports and fresh-water sources. Thus, this number by itself does not give any helpful measurement of human population density.

Several of the most densely populated territories in the world are city-states, microstates and dependencies.^[5][6] These territories have a relatively small area and a high urbanization level, with an economically specialized city population drawing also on rural resources outside the area, illustrating the difference between high population density and overpopulation.

Cities with high population densities are, by some, considered to be overpopulated, though this will depend on factors like quality of housing and infrastructure and access to resources.^[7] Most of the most densely populated cities are in Southeast Asia, though Cairo and Lagos in Africa also fall into this category.^[8]

City population and especially area are, however, heavily dependent on the definition of "urban area" used: densities are almost invariably higher for the central city area than when suburban settlements and the intervening rural areas are included, as in the areas of agglomeration or metropolitan area, the latter sometimes including neighboring cities. For instance, Milwaukee has a greater population density when just the inner city is measured, and the surrounding suburbs excluded.^[9]

In comparison, based on a world population of seven billion, the world's inhabitants, as a loose crowd taking up ten square feet (one square metre) per person (Jacobs Method), would occupy a space a little larger than Delaware's land area.^{[citation needed]}

By political boundaries

With population above 1,000,000

Rank	Country/Region	Population	Area (km2)	Density (Pop. per km2)
1	Singapore	5,535,000	719	7698
2	Hong Kong	7,234,800	1,104	6553
3	Gaza Strip	1,795,183	360	4987
4	Bahrain	1,404,900	750	1873
5	Bangladesh	161,609,000	147,570	1095
6	Taiwan	23,361,147	36,190	646
7	Mauritius	1,288,000	2,040	631
8	Lebanon	6,237,738	10,452	597
9	South Korea	51,529,338	99,720	517
10	Rwanda	11,262,564	26,338	428

With population above 10,000,000

Rank	Country/Region	Population	Area (km2)	Density (Pop. per km2)
1	Bangladesh	161,609,000	147,570	1095
2	Taiwan	23,361,147	36,190	646
3	South Korea	51,529,338	99,720	517
4	Rwanda	11,262,564	26,338	428
5	England	55,619,400	130,279	427
6	Netherlands	17,071,100	41,526	411
7	India	1,326,801,576	3,287,263	404
8	Haiti	10,413,211	27,750	375
9	Belgium	11,239,755	30,528	368
10	Burundi	10,114,505	27,834	363

Other methods of measurement

Although arithmetic density is the most common way of measuring population density, several other methods have been developed to provide a more accurate measure of population density over a specific area.

• 
  Arithmetic density: The total number of people / area of land (measured in square miles or square kilometers)


• 
  Physiological density: The total population / area of arable land
  


• 
  Agricultural density: The total rural population / area of arable land
  


• 
  Residential density: The number of people living in an urban area / area of residential land


• 
  Urban density: The number of people inhabiting an urban area / total area of urban land


• 
  Ecological optimum: The density of population that can be supported by the natural resources

See also

• Demography


• Human geography


• Idealized population


• Optimum population


• Population genetics


• Population health


• Population momentum


• Population pyramid


• Rural transport problem


• Small population size


• Distance sampling


• List of population concern organizations

Lists of entities by population density

• List of countries by population density


• List of cities by population density


• List of city districts by population density


• List of European cities proper by population density


• List of United States cities by population density


• List of islands by population density


• List of U.S. states by population density


• List of Australian suburbs by population density

References

External links

• Selected Current and Historic City, Ward & Neighborhood Density