thumb|upright=1.8|Population density (people per square kilometre) by country in 2023
thumb|upright=1.8|Population density (people per square kilometre) map of the world in 1994. In relation to the equator it is seen that the vast majority of human population lives in the [[Northern Hemisphere, where 67% of Earth's land area is.]]
Population density is a measurement of population size per unit land area. It is mostly applied to humans, but sometimes to other living organisms too. It is a key concept in population geography.
In botany and agronomy, it is known as plant density.
Biological population densities
Population density is population divided by total land area, sometimes including seas and oceans, as appropriate.
- Increased problems with locating sexual mates
- Increased inbreeding
<!-- This section is linked from List of countries by population density -->===Human densities===
thumb|upright=1.8|Population density (people per square kilometre) map of the world in 2020
Population density is the number of people per unit of area, usually transcribed as "per square kilometre" or square mile, and which may include or exclude, for example, areas of water or glaciers. Commonly this is calculated for a county, city, country, another territory or the entire world.
World population is around 8,000,000,000 and the Earth's total area (including land and water) is . Therefore, the worldwide human population density is approximately 8,000,000,000 ÷ 510,000,000 = . However, if only the Earth's land area of is taken into account, then human population density is . This includes all continental and island land area, including Antarctica. However, if Antarctica is excluded, then population density rises to over .
Several of the most densely populated territories in the world are city-states, microstates and urban dependencies. In fact, 95% of the world's population is concentrated on just 10% of the world's land. 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.
Deserts have very limited potential for growing crops as there is not enough rain to support them. Thus, their population density is generally low. However, some cities in the Middle East, such as Dubai, Abu Dhabi and Kuwait City, have been increasing in population and infrastructure growth at a fast pace.thumb|Mongolian Steppes. [[Mongolia is the least densely populated country in the world due to its harsh climate as a result of its geography.]]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. Very densely populated cities are mostly in Asia (particularly Southeast Asia); Africa's Lagos, Kinshasa, and Cairo; South America's Bogotá, Lima, and São Paulo; and Mexico City and Saint Petersburg also fall into this category.thumb|[[Monaco is currently the most densely populated nation in Europe.]]City population and especially area are, however, heavily dependent on the definition of "urban area" used: densities are almost invariably higher for the center only than when suburban settlements and intervening rural areas are included, as in the agglomeration or metropolitan area (the latter sometimes including neighboring cities).
In comparison, based on a world population of 8 billion, the world's inhabitants, if conceptualized as a loose crowd occupying just under per person (cf. Jacobs Method), would occupy an area of a little less than the land area of Puerto Rico, .
Countries and dependent territories
{| class="sortable wikitable" style="text-align:right"
|+ Population under 10,000,000
! rowspan="2" data-sort-type="number" | Rank
! rowspan="2" |Country or<br />dependent territory
! colspan="2" |Land Area
! rowspan="2" |Population
! colspan="2" |Density
|-
!km<sup>2</sup>
!sq mi
!per km<sup>2</sup>
!per sq mi
|-
| align="center" |1
| align="left" |' (China)
|
|650,834
|
|-
| align="center" |2
| align="left" |
|
|37,550
|
|-
| align="center" |3
| align="left" |
|
|6,036,900
|
|-
| align="center" |4
| align="left" |' (China)
|
|7,409,800
|
|-
| align="center" |5
| align="left" |' (Palestine)
|
|2,098,389
|
|-
| align="center" |6
| align="left"|' (UK)
|
|33,140
|
|-
| align="center" |7
| align="left" |
|
|1,451,200
|
|-
| align="center" |8
| align="left" |
|
|800
|
|-
| align="center" |9
| align="left" |
|
|475,701
|
|-
| align="center" |10
| align="left" |
|
|378,114
|
|}
{| class="sortable wikitable" style="text-align:right"
|+ Population above 10,000,000
! rowspan="2" data-sort-type="number" | Rank
! rowspan="2" |Country/Territory
! colspan="2" |Land Area
! rowspan="2" |Population
! colspan="2" |Density
|-
!km<sup>2</sup>
!sq mi
!per km<sup>2</sup>
!per sq mi
|-
| align="center" |1
| align="left" |
|
|170,329,768
|
|-
| align="center" |2
| align="left" |
|
|23,539,588
|
|-
| align="center" |3
| align="left" |
|
|13,246,394
|
|-
| align="center" |4
| align="left" |
|
|17,943,243
|
|-
| align="center" |5
| align="left" |
|
|51,439,038
|
|-
| align="center" |6
| align="left" |
|
|12,574,571
|
|-
| align="center" |7
| align="left" |
|
|1,374,547,140
|
|-
| align="center" |8
| align="left" |
|
|11,743,017
|
|-
| align="center" |9
| align="left" |
|
|11,554,449
|
|-
| align="center" |10
| align="left" |
|
|109,961,895
|
|}
Other methods of measurement
thumb|upright=1.6|This population [[cartogram of the European Union (2007–2012) uses areas and colors to represent population.]]
upright=1.8|thumb|Living population density by country
Although the arithmetic density is the most common way of measuring population density, several other methods have been developed to provide alternative measures of population density over a specific area.
- Arithmetic density: The total number of people / area of land
- 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
- Population weighted density: Also known as living density, population density at which the average person lives
See also
- Distance sampling
- Demography
- Human geography
- Idealised population
- List of population concern organizations
- Population dynamics
- Population decline
- Population growth
- Population genetics
- Population health
- Population momentum
- Population pyramid
- Rural transport problem
- Significant figures
- Small population size
Lists of entities by population density
- List of Australian suburbs by population density
- List of countries by population density
- List of cities by population density
- List of city districts by population density
- List of English districts by population density
- List of European Union cities proper by population density
- List of islands by population density
- List of states and territories of the United States by population density
Explanatory notes
References
External links
- Selected Current and Historic City, Ward & Neighborhood Density