Demographic density or population density is a measure used by Geography to assess the distribution of population in a given territory. It indicates the amount of people who inhabit a certain geographic space.
Also called relative population, the measure is expressed in inhabitants per square kilometer (inhabitant/km²).
This measure makes it possible to measure the distribution of the population residing in a given location, allowing to verify the population of the more and less populated areas.
This data makes it possible to calculate the distribution of the population residing in a given territory, allowing the verification of the more and less populated areas. However, like any other statistical data, it has some limitations, such as generalization, since the population is not evenly distributed by territorial extension.
There are also some external factors that can change the measure of demographic density in territories, which can be:
- Climate
- Offer of fertile land
- Rainfall distribution regime
- Land that allows the development of civil construction
- Economic factors: job offer
- Political factors: wars
According to data from the World Bank, the population density in the world has a total of 50.79 inhabitants per km², taking into account that the planet's area is 510 million km² and the population is estimated at 7.3 billion population.
Asia is the continent with the highest population density, with a total of 137.3 inhabitants per km². China alone has an estimated population density of 145.6 inhabitants per km² in 2014.
How to calculate population density
To calculate the population density of a region, we need to make a relation of two data: the absolute population, which corresponds to the total number of local inhabitants and the area occupied by this same population amount, which is usually expressed in km², according to the equation bellow:
Demographic Density in Brazil
The study of demographic density in Brazil allows us to observe the dynamics of population distribution throughout the national territory.
According to the estimate of the Brazilian Institute of Geography and Statistics - IBGE, in 2014 the number of inhabitants in Brazil was 202,768,562, while the country's official land area is 8,515,767.049 km². In other words, Brazil's demographic density in 2014 was 23.8 inhabitants per square kilometer.
However, considering that the population distribution in Brazil is quite unequal between regions, this relationship changes significantly, with regions with a very high concentration of people and others with little populated. The city of São Paulo, for example, has more than 7,300 inhabitants/km², while several cities in the North region have rates lower than 10 inhabitants/km².