While birth rates have dropped in MEDCs, birth rates are still high in LEDCs. Over the past 150 years improvements in health care and sanitation around the world have led to a drop in the death rate. When birth rates are higher than death rates the population of an area will increase. Death rates are number of people dying per 1000 people. The birth rate is the number of live babies born in a year for every 1000 people in the total population. The major reason for population changes, whether in an individual country or for the whole world, is the change in birth and death rates. This rapid growth in population has been called a population explosion. In 1820 the world's population reached 1 billion. The world's population is growing very rapidly. Limited job opportunities cause some areas to be sparsely populated e.g. Good job opportunities encourage high population densities, particularly in large cities in MEDCs and LEDCs around the world. Other groups of people prefer to be isolated e.g. Groups of people want to live close to each other for security e.g. Unstable countries tend to have lower population densities as people migrate e.g. The tables below illustrate this.Ĭountries with stable governments tend to have a high population density e.g. There are a range of human and natural factors that affect population density. This area contains a large land area and a relatively temperate climate. Areas of high population density tend to be located between 20° and 60°N. Some areas have a high population density while others have a low population density. The map above shows that world population distribution is uneven. Source: Columbia University's Center for International Earth Science Information Network The darker the colour the greater the population density. The map below is a choropleth (shading) map and illustrates population density. Population density is usually shown as the number of people per square kilometer. Population density is calculated by dividing the number of people by area. Population density is a measurement of the number of people in an area. Places which are densely populated are habitable environments e.g. These are usually places with hostile environments e.g. Sparsely populated places tend to be difficult places to live. Places which are densely populated contain many people. Places which are sparsely populated contain few people. Monaco in South 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.Population distribution means the pattern of where people live. Increased problems with locating sexual mates.Examples of the causes in low population densities include: This is called the Allee effect after the scientist who identified it. Population density is population divided by total land area or water volume, as appropriate.Low densities may cause an extinction vortex and lead to further reduced fertility. Commonly this may be calculated for a county, city, country, another territory, or the entire world. It is frequently applied to living organisms, and particularly to humans.įor 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). Population density is a measurement of population per unit area or unit volume it is a quantity of type number density. This chart shows the Population Density (per square kilometer) by country in 2015.

Population per square kilometre