What are the reasons for low, medium and high population density in residential areas?
Answers
For humans, population density is the number of people per unit of area, usually quoted per square kilometre or square mile, and which may include or exclude for example areas of water or glaciers. The world's population is around 7,500,000,000[3] and Earth's total area (including land and water) is 510,000,000 km2 (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 is 50 per km2 (129 per sq. mi.). 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. mi.).[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, additional criteria are needed to make simple population density values useful.