These regional differences persist within each county type. Among rural counties, a majority in the Northeast and Midwest lost population since , while a majority in the South and especially the West gained population.
One factor behind the regional difference is that rural counties in the Northeast and Midwest were more likely than other rural areas to have more deaths than births. These counties also were more likely to have experienced a net loss of migrants — more people moving out than moving in. The population trends of rural counties are linked to their economic profiles.
The total population of rural counties with recreation-based and government-based economies grew more since than the populations of other rural county types. One reason recreation-based counties grew was that they had a net gain of new residents who moved from other U.
S counties, the only rural county type to have a gain in net domestic migration. An analysis by the Population Reference Bureau found that rural recreation-based counties were especially likely to have growing numbers of residents 65 and older, while rural farming-based counties were losing residents in that age group. Among suburban and small metro counties, about a quarter of the ones in the Northeast and Midwest lost population since , a higher share than in other regions.
A majority of Northeast and Midwest suburban counties had a net gain of migrants, but that was mainly due to immigration. A majority had a net loss of residents to urban or rural U. A key demographic trend shaping the makeup of local populations, as well as the nation as a whole, is the rising number of older Americans. The Baby Boom generation, born between and , began turning 65 in , and all will have reached that age by While the population is aging in all three county types, this is happening more rapidly in U.
Nationally and in each county type, the older adult population grew more sharply since than any other age group — young children, school-age children, young adults or middle-aged adults. In rural areas, the population younger than 18 declined during this period. As a result, in each county type, adults ages 65 and older now make up a larger share of the total population than in The nation is becoming more racially and ethnically diverse, but these changes have been more muted in rural counties compared with urban and suburban ones.
The white share of the population fell 8 percentage points since in the suburbs, 7 points in the urban core and only 3 points in rural counties. Overall, the U. While the share of the non-Hispanic whites has declined, the number of whites grew in the nation overall — and in suburban counties as a whole — since But the white population did not grow as sharply as other groups did, leading to a decline in the white share of the total U.
In urban counties, the decline in the share of the white population was due both to a decrease in the number of whites and an increase in the size of other populations, chiefly Hispanics. In rural counties, the white population also decreased and other groups also increased in size, but the impact was more modest on the white share of the population because whites are so large a proportion of rural residents.
The foreign-born population is not evenly distributed across county types; immigrants tend to be concentrated in big metropolitan areas. In fact, about half live in urban counties, where they make up a higher share of the total than in suburban or rural counties. Wastewater from human settlements contains organic material and nutrients; industrial wastewater contains many different types of toxic pollutant.
These make the water unsafe for humans to use for many purposes including drinking and irrigation, as well as harming the fish and other animals and plants living in the water.
Any changes to the quality of surface water also affects groundwater because they are linked by the processes of the water cycle so pollutants from the surface will infiltrate down and contaminate soil and groundwater as well.
In many towns and cities solid waste management is inefficient or non-existent. Solid waste management means the proper collection, transfer, recycling and disposal of all the solid material we throw away, including plastics, paper and cardboard, food wastes, electrical waste, etc.
It also includes industrial, hospital and institutional wastes which often contain pathogens as well as hazardous and toxic chemicals, which need special care. Urban waste often ends up in illegal dumps on streets, open spaces, wastelands, drains or rivers. This is frequently a problem in peri-urban areas, which are convenient for dumping wastes because of the availability of open space and ease of access from central urban areas.
This can lead to the pollution of groundwater and surface waters which may be used as a source for drinking water. Sometimes the wastes are collected and taken to legalised waste disposal sites but these are not always properly managed to protect water bodies and groundwater. The combustion of solid waste creates yet another environmental problem.
People want to get rid of the wastes and they will burn them in their backyards if there is no collection system Figure 5. Air quality in towns and cities is frequently very poor as a result of air pollution from many different sources Figure 5.
These include:. Poor air quality has a significant impact on the health of many urban residents as well as leaving a damaging and unsightly layer of dust on plants, buildings and other surfaces.
Urbanisation can have both positive and negative effects on health. The main benefits are associated with easier access to hospitals, clinics and health services in general. If you live close to these services you can reach a doctor in minutes rather than hours or days, so this improves emergency care and general health. There are also benefits from easier access to sources of information such as radio and television which may be used to communicate information about health to the general public.
For example, women living in towns and cities are more likely to be informed about family planning, which results in reduction in family size and less frequent childbirth, with consequent benefits to general health. However, urban life can also damage your health. Poor environment, housing and living conditions are the main reasons for poor health in urban areas. Contamination of water sources can cause epidemics of waterborne disease.
Close proximity to other people can make the spread of many types of infectious disease more likely. The polluted air can also cause respiratory disease and contribute to premature deaths among more vulnerable sections of the population such as older people and children.
Population movements also put pressure on food supplies and on food distribution. As people migrate to the cities, they tend to use purchased food instead of their own crops and this makes them more vulnerable to changes in food prices. As the population grows and the demand for water and land increases, it becomes difficult to increase food production in a sustainable way.
The increase in urban demand, combined with a loss of agricultural land, means more pressure on rural people to produce food for the growing number of urban people. Furthermore, pollution from urban areas can disrupt food supply. For example, fisheries are often damaged by urban domestic wastes and liquid effluents from city-based industries.
Effluent is another word for wastewater that flows out from a source. In several Ethiopian cities, such as Bahir Dar, Hawassa, Bishoftu and others, untreated wastes are dumped into nearby lakes, which can damage the fish stocks Figure 5.
The process of urbanisation has positive as well as negative economic and social changes. The positive effects include economic development, and education. However, urbanisation places stresses on existing social services and infrastructure. Crime, prostitution, drug abuse and street children are all negative effects of urbanisation.
Also there tends to be a lack of social support for children in school and home by their hard-working, usually poor, parents. Inadequate income, overcrowded housing and poor living conditions create a fertile ground for the development of violence. Crime in the city can create a sense of insecurity in its inhabitants. This unsafe feeling in city streets separates residential areas into higher-income and lower-income groups, which reduces the sense of community and forms areas with dissimilar incomes, costs and security levels.
In the next study session we will look at some of the ways in which these problems and challenges can be addressed by considering the future demands for urban living and by taking a planned approach to the development of new urban areas. Now that you have completed this study session, you can assess how well you have achieved its Learning Outcomes by answering these questions. Urbanisation is an ……………… in the number of people living in towns and cities.
The two causes of urbanisation are natural population increase and ……………… Urbanisation affects all sizes of settlements from small villages to towns to cities, leading up to the growth of ……………… which have more than ten million people. Rapid urbanisation often means that ……………… areas immediately around a city grow more rapidly than urban centres and this can lead to development of ………………. Multifamily dwellings have the added benefit of being more energy efficient and they require less resources per person.
Cities are also walkable and have public transportation options that can make cars less of a necessity. And above all, densely populated areas make it possible to protect other open spaces to serve as wildlife habitat, farmland, conservation areas, or oxygen-producing forests. But of course, there are ecological downsides to cities as well. Concentrations of people mean concentrations of pollutants and trash. Cities produce up to 70 percent of global CO2 emissions and smog is becoming a common feature in many urban landscapes.
Large swaths of continuous pavement prevent water drainage and boost temperatures. Without proper infrastructure, cities also risk having waste — both trash and human waste — clogging waterways and causing damage. It is predicted that most future urban growth will happen in settlements currently home to between , and ,00 people, and if this is to be done sustainably, planning is a must.
You are using an outdated browser Internet Explorer not supported. Please upgrade your browser to engage in this experience. Based on this new definition, the world is already much more urbanised than previously thought. According to the same new definition, urban centres have almost doubled in number from more than 6, in to more than 13, in and their population size has also grown.
In the majority of countries population grows faster in urban areas than in rural ones. Over the last 25 years, cities globally have grown in size by an area equal to that of Romania.
In , urban areas hosted some 5. While in the rest of the world the urban population increased faster than or at roughly the same rate as the built-up area, in Europe and Northern America the inverse occurred, meaning that more land is now being consumed to accommodate new citizens than in the past.
Globally, urbanisation is occurring at different rates — considerably faster in developing regions than in the developed ones. Africa is expected to be the fastest urbani sing region: in the last 25 years, urban population has more than doubled almost all across sub-Saharan Africa.
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