Definition: Various ills caused by over-concentration of urban population, industry and traffic. Subject: geography (first-class subject);
In urban geography (two disciplines), a series of diseases caused by social contradictions caused by overpopulation are called urban diseases.
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Urban Diseases-Overview
Urban disease The so-called "urban disease" refers to a series of social problems caused by the excessive concentration of population in big cities, which is manifested in the blind expansion of urban planning and construction to the surrounding areas, occupying a large number of cultivated land, making the contradiction between people and land more acute. Due to the overpopulation of the city and the concentration of industry and transportation, a series of diseases caused by social contradictions have become urban diseases.
Urbanization in developing countries, also known as urban disease, has complicated reasons, first of all, economic reasons.
Some people refer to these problems as urban diseases. Almost all countries have faced or are facing urban diseases, but the severity of urban diseases can be different due to different government attention and management methods. Urban diseases in Latin American countries are more serious than those in developed countries.
These negative effects brought by urban development are called urban diseases, which appeared in many cities such as Tokyo and new york decades ago. However, no one has provided convincing evidence that urban diseases have led to the decline of cities.
During the industrial revolution, the rapid development of cities often exceeded the bearing capacity of social resources, leading to the emergence of various "urban diseases", mainly including housing shortage, serious pollution and deterioration of sanitary conditions. Early capitalist countries took a series of measures to control "urban diseases", but the effect was often not good.
Urban disease-population agglomeration 1, megacities usually have a strong agglomeration effect on population, and the rapid agglomeration of population has become one of the important reasons for the development of megacities. In the process of rapid population gathering, once urban construction and management can't keep up with the rapid growth demand, the supply of various urban infrastructure lags behind the urban population growth, which will lead to a series of contradictions and urban diseases such as environmental pollution, employment difficulties, and deterioration of public security.
2. Around the end of19, the urban population in Britain expanded rapidly, resulting in a shortage of housing and slums everywhere; Lack of public health facilities, serious air and water pollution and bad environment; The employment competition is fierce, and the workers are in a difficult situation; The crime rate remains high and so on.
3. After Latin America entered the stage of industrialization in the middle of the 20th century, the urban population gathered rapidly, and the level of urbanization (the proportion of urban population to the total population) even surpassed that of developed countries, resulting in "excessive urbanization" (or "advanced urbanization"). Urban Disease-Traffic Congestion
Urban disease 1, traffic problem has always been one of the primary problems in big cities. With the rapid urbanization and rapid population expansion in big cities, the contradiction between urban traffic demand and traffic supply has become increasingly prominent, which is mainly manifested in a series of problems such as traffic congestion, pollution and safety.
2. Traffic congestion will not only lead to the decline of economic and social functions, but also lead to the continuous deterioration of urban living environment and become a "chronic urban disease" that hinders development. The most direct impact of traffic congestion on social life is to increase the travel time and cost of residents. The increase of travel cost not only affects work efficiency, but also inhibits people's daily activities, greatly reducing the vitality of the city and the quality of life of residents.
3. Traffic congestion also leads to an increase in accidents, which further aggravates the congestion. According to relevant statistics, the economic loss caused by traffic accidents in Europe is as high as 50 billion dollars every year.
4. Traffic jam also destroys the urban environment. With the rapid growth of motor vehicles, traffic pollution to the environment is becoming more and more serious, and it has gradually become the main source of pollution for the deterioration of urban environmental quality. According to the test report of London in 1990s, 74% of nitrogen oxides in the atmosphere come from automobile exhaust emissions. Traffic congestion causes vehicles to drive at low speed. Frequent stopping and starting not only increases the energy consumption of vehicles, but also increases the exhaust emission and noise. Urban disease-environmental pollution
Urban disease 1. In the past century, with global warming as the main feature, great changes have taken place in the global climate and environment, such as water shortage, ecosystem degradation, increased soil erosion, sharp decline in biodiversity, depletion of the ozone layer, changes in atmospheric chemical composition and so on.
2. According to the prediction of the Intergovernmental Panel on Climate Change, global warming will continue at a faster speed in the future, and the temperature will rise 100/00, which will bring more serious impacts on the global environment, such as crop production reduction, obvious increase in the frequency and damage speed of diseases and insect pests, and intensified water shortage.
3. Environmental pollution has turned the city from the traditional public health problems (such as water-borne diseases, malnutrition, lack of medical services, etc.). ) to modern health crisis, including air pollution, noise, vibration and mental stress caused by industry and traffic.
4. Environmental pollution has a great influence on urban economy. The World Bank estimates that the health cost and productivity loss caused by pollution are equivalent to about 65,438+0% to 5% of GDP. Urban disease-resource shortage 1,
Urban diseases At present, half of the rivers in the world are greatly reduced or seriously polluted, and more than 80 countries or 40% of the world's population are seriously short of water. If this trend is not contained, more than 55% of the global population will face water shortage in the next 30 years.
2. Among the countries or regions that lack water, the water shortage in big cities is the most serious. According to the prediction of relevant UN agencies, by 20 10, large and medium-sized cities in both developing and developed countries, including Beijing, Shanghai, Houston, Jakarta, Los Angeles, Warsaw, Cairo, Lagos, Dhaka, S? o Paulo, Mexico City and Singapore, will face serious water shortage.
3. The shortage of land resources is also an inevitable problem in the process of urbanization of international metropolis. Due to the absolute rigidity of land supply, some metropolises, such as Tokyo, new york, London, etc., have encountered serious land shortage in the process of a large number of people and industries gathering in central cities, and the constraints of land on the sustainable development of modern metropolises are more prominent. How to open up new development space and expand regional scope has become an inevitable requirement for major cities to achieve sustainable development. Urban disease-urban poverty
Urban disease 1, slum problem is a unique phenomenon in the process of accelerating urbanization in large and medium-sized cities in developing countries. Most of the poor are concentrated in cities, and most of the urban poor live in slums, such as Mumbai, India and Sao Paulo, Brazil.
2. The social problems brought by slums mainly include: most slum dwellers live below the poverty line, unable to enjoy the fruits of economic and social development that citizens should enjoy, and poor living, travel, health and education conditions, which not only affect the development of contemporary people, but also affect the development of the next generation.
2. The great difference of living standards has caused the estrangement of people's feelings. In addition, slums are divorced from the community and normal social management. Some slums are controlled by the underworld and become dens of urban crime. Slums have become the biggest feature of this world-famous port city and India's economic center city.
The appearance of slums is largely caused by the influx of migrants and the excessive income gap of the population in this city. There are mainly the following reasons: First, the serious inequality of land ownership has caused a large number of landless farmers. Take Brazil as an example, most of Brazil's land has been controlled by a few big landlords, and a large number of landless farmers have moved to cities, and this flow is one-way and cannot flow back to the countryside.
4. There is a serious shortage of employment opportunities in the process of urbanization. Unemployment, underemployment and poor quality of employment are the important reasons for the long-term existence of a large number of urban poor people. In the process of urbanization, developing countries often shift their industrial focus to capital and technology-intensive sectors, resulting in a large number of laborers entering the traditional service industry and the informal sector in the tertiary industry. Generally speaking, the wages in the informal employment sector are only half of those in the formal sector. No labor contract, no social security and no legal protection.
5. Urban planning, construction land, infrastructure and community development have not fully considered the requirements of low-income people. 80% people living in urban slums earn less than the minimum wage, so it is difficult for them to get land and housing for building houses in cities, and they can't return to the countryside. They can only illegally occupy urban public land (such as hilltops and public land in urban-rural fringe) and private land, build humble houses and engage in illegal construction.
6. Public policy is not perfect. For example, the national education expenditure is excessively inclined to secondary and higher education, and the primary education is relatively shrinking. In the secondary education stage, paying attention to general education and humanities education, ignoring secondary vocational and technical education and normal education, is not conducive to improving the education and employment situation of low-income children.
Urban Disease-Cause Analysis
Urban disease 1, 655 cities "go global", 183 cities should become "international metropolises". Looking back on the past ten years, the wave of city-building is surging, the enclosure planning is grand and the landmark construction is luxurious. After a lot of construction, people and money are wasted, and sometimes they fall into the embarrassment of poor image and poor economic development.
2. The symptoms of urban diseases are always surprisingly consistent: the slogan of swallowing mountains and rivers, incredible planning, billions of investments and difficult endings. Therefore, from the form of expression, "urban disease" does have epidemic characteristics, but this is not because our urban immunity is too poor, but because some managers have the same pathogenic gene-impetuous political impulse.
3. Adding the word "impetuous" is because officials have the impulse of political achievements. In a sense, the impulse of officials' political achievements is the driving force to develop one side's economy.
4, but this must be in a calm and sober state, after brainstorming and careful consideration, before it can be put into practice. Instead of being in an impetuous and fanatical state, making decisions without in-depth discussion and careful argumentation.
5. To prevent and control urban diseases is to standardize and supervise power, respect public opinion, and make public opinion an important force that can compete with power equally. Every public decision has extensive public participation, and the "urban disease" that wastes people and money can be cured.
Urban diseases-treatment methods
Countries in the Shanghai World Expo show the methods of treating urban diseases.
1. How to solve the pollution, congestion and safety problems of urban traffic? The prescription brought by odense Case Museum is to build special bicycle lanes in the whole city to restrict the development of automobiles.
2. The case Museum in Roa, France, put forward a plan to achieve medium density by balancing the height of the floor.
3. Urban visual pollution such as advertisements, signboards and graffiti has a long history. Taking Sao Paulo as an example, the "Clean City Act" was implemented, and in just two years, the overwhelming urban "psoriasis" was cleaned up, and the original style of the city was seen again.
4. The "Zero Carbon" Case Museum in London provides a realistic sample for realizing "zero carbon emission" and a set of completely feasible solutions for building a low-carbon society.
Urban Disease-Current Situation of China
Since 1950s, there has been an unprecedented phenomenon of urbanization in the world. At present, China is at the peak of urbanization. In the coming 10 year, there will be 870 million people living in cities in China, accounting for about half of the total population. At the same time, there will be 87 cities with a population of over 750,000, making them truly urbanized countries. [ 1]