Urbanization

Urbanization is the physical growth of rural or natural land into urban areas as a result of population in-migration to an existing urban area. Effects include change in density and administration services. While the exact definition and population size of urbanized areas varies among different countries, urbanization is attributed to growth of cities. Urbanization is also defined by the United Nations as movement of people from rural to urban areas with population growth equating to urban migration. The UN projects half the world population will live in urban areas at the end of 2008.

Through most of history, the human population has lived a rural life>

The world has experienced unprecedented urban growth in recent decades. In 2000, about 47 percent of the world's population lived in urban areas, about 2.8 billion. There are 411 cities over 1 million. More developed nations are about 76 percent urban, while 40 percent of residents of less developed countries live in urban areas. However, urbanization is occurring rapidly in many less developed countries. It is expected that 60 percent of the world population will be urban by 2030, and that most urban growth will occur in less developed countries.

What is an urban area?

An urban area may be defined by the number of residents, the population density, the percent of people not dependent upon agriculture, or the provision of such public utilities and services as electricity and education. Some countries define any place with a population of 2,500 or more as urban; others set a minimum of 20,000. There are no universal standards, and generally each country develops its own set of criteria for distinguishing urban areas. The United States defines urban as a city, town, or village with a minimum population of 2,500 people. The classification of metropolitan includes both urban areas as well as rural areas that are socially and economically integrated with a particular city.

When comparing countries it is often helpful to look beyond the proportion of populations that are rural or urban and instead consider the size of cities. Countries differ markedly in the distribution of their urban population. For example, many urban dwellers in Africa live in cities of fewer than 10,000 residents. In Argentina, 90 percent of the 2000 population was urban, and 38 percent of these people lived in just one city, Buenos Aires. In 2000, 39 percent of the world's urbanites lived in agglomerations of 1 million or more inhabitants, and 15 percent resided in agglomerations of 5 million or more. Only 8 percent of Americans live in cities of 1 million or more.

Migration or Natural Increase

A city grows through natural increase — the excess of births over deaths — and because the in-migration of people from other cities, rural areas, or countries is greater than out-migration. More developed and less developed countries of the world differ not only in the percent living in cities, but also in the way in which urbanization is occurring.

During the 19th and early 20th centuries, urbanization resulted from and contributed to industrialization. New job opportunities in the cities spurred the mass movement of surplus population away from the countryside. At the same time, migrants provided cheap, plentiful labour for the emerging factories. While the proportion increased through rural to urban migration, high death rates in the cities slowed urban growth. Cities were unhealthy places because of crowded living conditions, the prevalence of contagious diseases, and the lack of sanitation. Until the mid-1800s, the number of deaths exceeded births in many large European cities. Migration accounted for as much as 90 percent of city growth during this period.

Urbanization in most less developed countries in the past 50 years contrasts sharply with the experience of the more developed countries. Death rates have fallen faster in urban areas because of greater access to health services. Because birth rates are relatively high in most less developed countries, the rates of natural increase are also quite high in cities. Migration also fuels urban growth in less developed countries as people leave the countryside in search of better jobs.

The chart "Growth of urban agglomerations" shows population growth in selected cities. New York and London are typical of large cities in more developed countries that arose in the 1800s and early 1900s, reached their current size mid-century, and have since experienced slow growth or decline. Cities in some less developed countries, such as Mexico City, grew very rapidly between 1950 and 1980, and are growing more slowly now. Many Asian and African cities, such as Lagos and Bombay, are experiencing very rapid growth now and are projected to continue at this pace.

Counter-urbanisation

Counter-urbanisation is the movement of people out of cities, to the surrounding areas. Since 1950 this proccess has been occurring in MEDCs (More Economically Developed Countries). There are four main reasons for counter-urbanisation:

1. The increase in car ownership over the last 40 years means people are more mobile. This has led to an increase in commuting. Also, the growth in information technology (E-mail, faxes and video conferencing) means more people can work from home.

2. Urban areas are becoming increasing unpleasant place to live. This is the result of pollution, crime and traffic congestion.

3. More people tend to move when they retire.

4. New business parks on the edge of cities (on Greenfield sites) mean people no longer have to travel to the city centre. People now prefer to live on the outskirts of the city to be near where they work.

Megacities

As the population increases, more people will live in large cities. Many people will live in the growing number of cities with over 5 million habitants known as megacities. Just eight cities had populations of 5 million or more in 1950, two of them in less developed countries. Megacities numbered 41 in 2000. By 2015, 59 megacities will exist, 48 in less developed countries.
1. Tokyo (Japan) 27.2 million
2. Mexico City (Mexico), 16.9 million
3. Sao Paulo (Brazil) 16.8 million
4. New York (USA), 16.4 million
5. Bombay, India, 15.7 million 

By the turn of the century, cities of 10 million and larger will be more common. In 1950, only one city had more than 10 million inhabitants (see table, "Top 10 Largest Urban Agglomerations" below). By 2015, 23 cities are projected to hold over 10 million people; all but four will be in less developed countries.

Urbanozation in Slovak Republic

The rural society reacts differently to changing econimacal and social codnditions. The natural population growth in the rural regions in Slovakia fell from 5.32% to 2.16% within the period 1991-2001. The basic factor influencing the spatial distribution of migration flows is the geographical and econimical periphery of rural regions. The migration flows are directed from the eastern and northen economically underdeveloped regions to the developed regions loated in the western part of Slovakia.

The state and developement of demography indicators was different according to the size and type of towns and villages, There are too many small towns and villages, that cost a lot of public Money. Another important aspect is the number of small towns and villages increasing eastwards.

The change of population in towns and villages was almost identical, so there was no change in the degree of urbanisation/rural area of Slovakia in the year of 2000. The same growth of population could be seen in all types of towns represented by index 1.02-1.04.

More significant differences are in population changes of rural space. It can be stated that the bigger the village, the bigger of population, while in villages of under 500 inhabitants the decrease of population happens.

The decrease of population in towns is caused by very small or negative natural growth. Natural growth tends to decrease in both, towns and villages. In spite if this fact migration is very positive in villages, but does not compensate for the fall in natural growth.