Abstract
Urbanization refers to general increase in population and the amount of industrialization of a settlement. It includes increase in the number and extent of cities. It symbolizes the movement of people from rural to urban areas. Urbanization happens because of the increase in the extent and density of urban areas. Due to uncontrolled urbanization in India, environmental degradation has been occurring very rapidly and causing many problems like land insecurity, worsening water quality, excessive air pollution, noise and the problems of waste disposal.
This paper emphasizes on the effect of urbanization on environmental components mainly climate, biosphere, land and water resources. A case study of urbanization in India and metropolitan cities have been carried out leading to conclude on the existing causes of damage to the environment due to urbanization and preventive measures to keep a check on them. Although it is impossible to restrict urbanization it has to be ensured that urbanization proceeds in the right path causing minimum impact on environment.
Introduction
Urbanization is a process that leads to the growth of cities due to industrialization and economic development, and that leads to urban- specific changes in specialization, labour division and human behaviours. The population is growing at the rate of about 17 million annually which means a staggering 45,000 births per day and 31 births per minutes. If the current trend continues, by the year 2050, India would have 1620 million populations. Due to uncontrolled urbanization in India, environmental degradation has been occurring very rapidly and causing many problems like shortages of housing, worsening water quality, excessive air pollution, oise, dust and heat, and the problems of disposal of solid wastes and hazardous wastes. Probably most of the major environmental problems of the next century will result from the continuation and sharpening of existing problems that currently do not receive enough political attention. The problems are not necessarily noticed in many countries or then nothing is done even the situation has been detected. The most emerging issues are climate changes, freshwater scarcity, deforestation, and fresh water pollution and population growth.
These problems are very complex and their interactions are hard to define. It is very important to examine problems trough the social-economic-cultural system. Even the interconnections between environmental problems are now better known, we still lack exact information on how the issues are linked, on what degree they interact and what are the most effective measures. One problem is to integrate land- and water use planning to provide food and water security (UNEP 1999). The creation of heat island Materials like concrete, asphalt, bricks etc absorb and reflect energy differently than vegetation and soil. Cities remain warm in the night when the countryside has already cooled. IJREAS Volume 2, Issue 2 (February 2012) ISSN: 2249-3905 Changes in Air Quality Human activities release a wide range of emissions into the environment including carbon dioxide, carbon monoxide, ozone, sulphur oxides, nitrogen oxides, lead, and many other pollutants. Changes in Patterns of Precipitation
Cities often receive more rain than the surrounding countryside since dust can provoke the condensation of water vapour into rain droplets. [B] Erosion and other changes in land quality Rapid development can result in very high levels of erosion and sedimentation in river channels. Pollution Pollutants are often dispersed across cities or concentrated in industrial areas or waste sites. Lead- based paint used on roads and highways and on buildings is one such example of a widely dispersed pollutant that found its way into soil.
Burying tremendous amounts of waste in the ground at municipal and industrial dumps.Flow of Water into Streams Natural vegetation and undisturbed soil are replaced with concrete, asphalt, brick, and other impermeable surfaces. This means that, when it rains, water is less likely to be absorbed into the ground and, instead, flows directly into river channels. Flow of Water through Streams Higher, faster peak flows change streams channels that have evolved over centuries under natural conditions.
Flooding can be a major problem as cities grow and stream channels attempt to keep up with these changes. 3. Degraded Water Quality The water quality has degraded with time due to urbanization that ultimately leads to increased sedimentation there by also increasing the pollutant in run-off. IJREAS Volume 2, Issue 2 (February 2012) Modification of Habitats The fertilizers that spread across lawns find its way into water channels where it promotes the growth of plants at the expense of fish. The waste dumped into streams lowers oxygen levels during its decay and cause the die-off of plants and animals. 2. Destruction of Habitats There is also complete eradication of habitats as an outcome of urbanization and native species are pushed out of cities. 3. Creation of New Habitats New habitats are also created for some native and non-native species. Cities also create habitats for some species considered pests, such as pigeons, sparrows, rats, mice, flies and mosquitoes. Urbanization has, for example, liminated many bat colonies in caves, but has provided sites such as bridges for these species to nest. Impact of Urbanization on the Environmental Quality in the Metropolitan Cities of India Urbanisation and its allied process have made a profound impact on the environment of the metropolitan cities of India. It has been accepted by the United Nations that it is quite impossible for developing countries to provide in advance the urban planning and design because it is not possible to accurately project the urban growth. (i) Slum Situation in India and its Metropolitan Cities: The Govt. f India Slum Areas (Improvement and Clearance) Act of 1954 defines a slum ‘as any predominantly residential areas, in which light or sanitary facilities or any combination of these factors are detrimental to the safety, health or morals’. The vast majority of the people who migrated to the city were attracted by opportunity and comforts offered by modernization. They belonged to the working class and found it difficult to secure accommodation within their means. So, they squatted on every open space available, as near their workplaces as possible and put up huts with cheap building materials.
In this way slums grew in number and population. Total and slum population in India according to size/class of towns during 1991 shows that 41% of the total slum population was residing in million plus cities, where 27% f total population of India resides (Table 5). However, cities with population between 0. 5 million to 1 million have only 9% of total slum population where 20% of total population was residing. Further, cities with population between 0. 3 million to 0. 5 million have only 6% of total slum population where 19% of total population was residing. This shows that cities with population between 0. to 1 million and cities with population between 0. 3 to 0. 5 million have a very less percentage of slum population whereas million plus cities have more percentage of slum population. It reveals that the opportunity in the medium city is less than the million cities. Therefore the unskilled population is more attracted towards the million cities and thus joins the slums for their residence.
On the other hand, the towns with population less than 50,000 shows little more percentage of total slum population (21%) than its share of total population (18%). It shows the poor housing quality in the small towns and also may be because the emi-pucca and kachcha houses may be identified as slum. Slum population is a serious problem of the mega-cities of India. A large population of Mumbai, Kolkata and Delhi lives in slum, despite of several Government housing policies.
However, Kolkata and Delhi had not shown as severe condition as Mumbai. The proportion of slum population was 30% and 18% in 1981 in Kolkata and Delhi, which increased to 36% and 23% respectively. On the other hand, it is little bit comfortable sign for Kolkata and Delhi that in 2001 the proportion of slum population has decreased to 33% and 19%, respectively. Although Chennai has lowest slum population among the four metropolitan cities yet it has experienced continuous increase in the slum population over the three decades.
There were 14% slum population in Chennai in 1981, which increased to 15% in 1991 and further 18% in 2001. (ii) Status of Municipal solid waste generation and collection in Metropolitan Cities of India Mumbai generates the largest amount of Municipal solid waste in 1996, which is 5355 tonnes/day followed by Delhi (4000 tonnes/day), Kolkata (3692 tonnes/day) and Chennai, which is 3124 tonnes/day(Sunil Kumar, et al. , 2009). But if we consider the per capita generation of solid waste, it is largest in Chennai, which is about 700 gms/day.
The lowest per capita waste generation is in Kolkata, which is about 350 gms/day. (iii) Growth in motor vehicles in India and in Metropolitan Cities: Within 10 years from 2000 to 2010 there has been almost a three-fold increase in the number motor vehicles in India. On an average 10% increase has been found in each year, which is a serious concern for air pollution. Among all the vehicular emission loads, the amount of Carbon monoxide (CO) was found highest followed by Hydro Carbon and Nitrogen Oxide in all the three metropolitan cities.
Surveys shows that in Delhi the numbers of registered vehicles are highest, the vehicular emission load also substantiates it, as all the elements were found highest in Delhi. The ingredient of vehicular emission load affects the health of the people and deteriorates the quality of life of the residence of metro cities. (iv) Waste Water Generation, Collection and Treatment in Metropolitan Cities Water resources are diminishing not just because of large population numbers but also because of wasteful consumption and neglect of conservation.
With rapid urbanization and industrialization, huge quantities of wastewater enter rivers. The volume of domestic wastewater generation is highest in the metropolitan city of Mumbai, which is 2228. 1 ml/d followed by Kolkata (1383 ml/d) and Delhi (1270 ml/d) and the lowest is in Chennai (only 276 ml/ The generation of industrial wastewater is also highest in Mumbai. Again looking at the percentage of wastewater collection from the four metropolitan cities, Chennai and Mumbai performs better than Delhi and Kolkata.
Regarding the treatment of the collected wastewater in all the metro cities, the water is disposed only after primary and secondary treatment. Urbanization can be good for the environment Urbanization degrades the environment, according to conventional wisdom. This view has led many developing countries to limit rural—urban migration and curb urban expansion. But this view is incorrect. There are a number of reasons urbanization can be good for the environment, if managed properly. First, urbanization brings higher productivity because of its positive externalities and economies of scale.
Asian urban productivity is more than 5 times that of rural areas. The same output can be produced using fewer resources with urban agglomeration than without. In this sense, urbanization reduces the ecological footprint. The service sector requires urbanization because it needs a concentration of clients. As services generally pollute less than manufacturing, this aspect of urbanization is also beneficial to the environment. Second, for any given population, the high urban density is benign for the environment.
The urban economics literature shows that compactness is a key determinant of energy use. High density can make public transport more viable and reduce the length of trips. Urban living encourages walking and cycling rather than driving. Third, environment-friendly infrastructure and public services such as piped water, sanitation, and waste management are much easier and more economical to construct, maintain, and operate in an urban setting. Urbanization allows more people to have access to environment-friendly facilities and services at affordable prices.
Fourth, urbanization drives innovation, including green technologies. In the long term, environment-friendly equipment, machines, vehicles, and utilities will determine the future of the green economy. Green innovations in Asia’s cities will be supported by the region’s vast market as the billions of people who will be buying energy-efficient products will create opportunities and incentives for entrepreneurs to invest in developing such products. Finally, the higher standard of living associated with urbanization provides people with better food, education, housing, and health care.
Urban growth generates revenues that fund infrastructure projects, reducing congestion and improving public health. Urbanization fosters a pro-environment stance among property owners and the middle class, which is crucial for the introduction and enforcement of environmental laws and regulations. Of course, urbanization also comes with costs. Millions of people are migrating to Asian cities and companies are locating there to employ them. Urban sprawl and industrial activities, such as power generation, transportation, construction, garbage and waste disposal, harm the environment.
An assessment of the impact of urbanization on the environment must balance its benign and adverse effects. Figure 1 shows that the Asian environment–urbanization relationship varies, depending on the level of development. Once a certain threshold has been reached, urbanization becomes good for the environment in terms of lower emissions of CO2 and particle pollution (PM10). Figure 1: Environment–Urbanization Relationship in Asia CO2 = carbon dioxide; PM10 = particulate matter with diameter of 10 micrometers or less; µg/m3 = micrograms per cubic meter; t = ton.
The graph’s curves show that cities in the 2000s enjoyed a better environment at the same level of urbanization than cities in the 1990s. To ensure green urbanization, developing countries need to continue the downward shift by adopting the following recommendations. The first priority is to improve energy efficiency and conservation through appropriate pricing, regulations, and public sector support. It is vital to get prices right so that they incorporate the full social costs and benefits, and ensure the efficient allocation of resources.
This can be done by imposing congestion and emission charges, as in Singapore, and by removing inefficient subsidies, as in Indonesia. Other examples are the introduction of carbon taxes, as in the Republic of Korea, and increasing block pricing for water, electricity, and other public utilities, as in the Philippines. Countries need to introduce regulations and standards in a timely manner. These can correct for market or coordination failures on air, water, vehicles, and appliances, as in India. The government can build green industrial zones to attract manufacturing, as in Indonesia.
Improved regulations can reduce or prevent urban sprawl. Cities need to build rapid public transport systems to improve connectivity and reduce pollution. Speedy connections to and from satellite cities can ease congestion in central megacity hubs. Rapid bus transit systems, as in the People’s Republic of China (PRC), and subways, as in India, can reduce environmental degradation in densely populated cities and improve the quality of life. The second priority is to promote renewable resources and new energy technologies.
Waste-to-energy plants reduce pollution and generate energy, as in the Philippines and Thailand. Green technology can be acquired either by importation or innovation through research and development, as in the PRC. The PRC is building new towns and satellite cities using renewable energy as primary energy sources. Urban sprawl can be tackled by reviving city centers and developing compact, walkable satellite cities centered on efficient train, light rail, or subway systems, without heavy reliance on highways and major roads.
The third priority is to help the poor by reducing disaster risks and improving slum conditions. Disaster risk reduction can be done by building dwellings in safe areas, improving housing affordability for the poor, and investing in drainage infrastructure and climate forecast technology. Policies to improve slum conditions include providing basic services, granting land titles to slum dwellers, and issuing housing vouchers linked in value to the length of a resident’s tenure in the city.
The fourth priority is to strengthen public finance, transparency, and accountability. Public finance can be improved by broadening the tax and revenue base and by increasing the access of urban governments to broader and deeper capital markets in order to lower infrastructure and public service costs. Politicians can be encouraged to do the right thing by disclosing city government performance to the public and nongovernment organizations, and having national competitions and campaigns to encourage a “race to the top” to reward high achievement.
India’s urban expansion to impact environment: United Nations report Growing urbanisation in India will have a significant impact on environment and the rich biodiversity which is critical to the well-being of people, a United Nations Assessment report said here. ‘The Cities and Biodiversity Outlook’, which was released today at the UN’s Convention on Biological Diversity (CBD) COP-11, said the global urban expansion will draw heavily on water among other natural resources and consume prime agricultural land. India’s population is currently about 30 per cent urban and is expected to become 50 per cent by about 2044. This will have significant implications for the country’s environment, ecology and sustainability,” the report said. “India already contains three of the world’s ten largest cities- Delhi, Mumbai and Kolkata -as well as three of the world’s ten fastest growing cities- Ghaziabad, Surat and Faridabad,” it added. The world’s total urban area is expected to triple between 2000 and 2030, with urban population set to double to around billion in the same period. Urban expansion is occurring fast in areas close to biodiversity hotspots and coastal zones, the report said. In rapidly urbanising regions, such as large and mid-sized settlements in sub-saharan Africa, India and China, resources to implement sustainable urban planning are often lacking, the report observed. According to Thomas Elmqvist, scientific editor of the report, cities need to learn better how to protect and enhance biodiversity as this is extremely critical to the well-being of people.
However, lifestyle changes in India due to urbanisation may decrease pressure on forests, as usage of firewood and charcoal is reduced, the report also said. On China, the report said the country, which has around 50 per cent of the population living in cities, is in the middle of its urbanisation transition. By 2030, its urban population is expected to exceed 900 million, an increase of more than 300 million from today, the report states. In Europe, the current urbanisation level is 70-80 per cent and the urban growth in recent decades has mostly been in the form of land expansion rather than population growth. Many European and North American cities have exhibited trends of shrinking and of shifting patterns of population in central parts of cities, coupled with sprawl in outer suburbs and exurban areas,” it said. Braulio Ferreira De Souza Dias, the Executive Secretary of the Convention on Biological Diversity, said the way cities are designed, the way people live in them and the policy decisions of local authorities will define to a large extent future global sustainability.
The report was produced by CBD in partnership with the Stockholm Resilience Centre and Local Governments for Sustainability.
Conclusion
It is evident from the studies that, each and every environmental and social parameter of the Indian metropolitan cities are very much deprived. In case adequate steps are not taken to prevent pollution and to improve the quality of life by providing more social amenities, the life of the urban dwellers of India may become more miserable which may be the cause of health hazards and worst devastation. To achieve this, the urban population must be controlled.
Also the number of people living in the metropolitan city demanding the resources land, air and water apart from other biological resources must be limited. Vehicular pollution control in metropolitan cities and other cities deserves top priority. Urgent attention should be given to reduce the generation of solid waste at the sources through mandatory standards and regulation fee and tax incentives, and education and voluntary compliance. Improved technologies should be developed for waste collection, treatment, and disposal in order to ensure proper solid waste management.
Evidences from the present study indicates that the maintenance of high quality of life in metropolitan cities requires the innovative economic growth potential as well as our urban population in the metro cities should be stabilized at sufficient level in lieu with the resources available and the protection of environmental quality leading towards sustainable development. Serious attention should be given to the need for improving urban strategies, which promote efficiency in resource use. There is an urgent need to tackle the problem of population growth in the metropolitan cities in a rational manner.
