Urbanization process is not symmetrical around the world. The issues and impacts of the urbanization are not limited and cover a numbers of areas that have been influenced by the extension of cities with the passage of time. Apart from the predictable changes in streams, the depletion of agricultural land is another global issue which relates to the growth of cities in the developing countries. Not only the streams and lands are being affected but the global climate has been changing as most urban areas of Asia, Africa and Latin American are facing high heat waves. Strong city planning management is essential to avoid the unsustainable societies there is a requirement of appropriate planning of cities and a responsible local and regional government.
Urbanism is not a modern phenomena, its roots lies since 5000 B.C. According to Gideon Sjoberg cites can be divided into four groups: 1- Folk-preliterate, 2- feudal, 3- Pre-industrial, 4- Urban-industrial. This succession depicts an obvious societal development. The rise of the pre-industrial phase was introduced after the Victorian gothic architecture with the support of political powers. The true expansion of urban area was highlighted when Europe entered in the Urban-industrial stage, the huge building and economically commercial organizations became the prominent core of the urban areas. Urbanization is considered as a transitory process to promote advantages such as exchange of knowledge thus flourishing the economical growth. But the optimal extent of urbanization has not been quantified in each stage of development that means when a country supports the urbanism typically they will not improve their productive growth. Fundamentally, there should be a determined optimal degree of urbanism for each of the developmental stage, which would detects the over or under urbanization in relation to the growth.
Urbanization and Waterbodies:
The issues and impacts of the urbanization are not limited and cover a numbers of areas that have been influences by the extension of cities with the passage of time. When we talk about streams and rivers in ecosystems, there are three major pathways that modify streams of the ecosystem according to the EPA. One of them is the removal of the plant habitat and communities along the river edge which is called riparian vegetation that directly alters the hydrology and the habitat of the area. Secondly, waste water load caused by human and industrial activities mix up with the streams polluting the natural ecology of water nearby. And lastly the artificial structures (roads, driveways or parking areas) that are covered with either stones or bricks result in high transmittal of storm water and contaminations in the streams. The predictable changes in streams were referred as “urban stream syndrome” after noticing the concrete effects on the urban streams that were highly associated with the reduction in natural biotic system.
The depletion of agricultural land is another global issue which relates to the growth of cities in the developing countries. The area of cultivatable land is decreasing rapidly with some serious threats to the agricultural sustainability. This impact cannot be avoided because this can cause several calamities to the farmers and their livelihood in terms of food security, increase in poverty, insufficient sustainable environmental factors. Even in the developed countries like The United KIndgom, urbanization can not be ignored, Figure 1 shows an example of rapid urbanizartion in Edinburgh during the 1990 anf 2015.
Urbanization and Industries:
The largest quantum of environmental hazards is produced by the industries. The industrial revolution has long been connected with a variety of human and environmental hazards. Regardless the nature of industry whether its a chemical, paper and pulp, cement, textile, glass, ceramics, iron and steel, leather and tanning or petroleum refining industry, all of them has some serious impacts on the air, water and soil of the environmental. Several toxic emissions like SO2, NOx, CO, CH4, lead, chromium, benzene, mercury, nickel, zinc, hydrocarbons, leather dust, arsenic, metals residues, and ultraviolet radiations are generated by the industrial processes in the surrounding air. The water is being polluted by the emission of organic chemicals, heavy metals, suspended solids, oils and other hazardous effluents emitted by the industries. Whereas due is the chemical processes, inappropriate waste disposal management, mismanaged metal disposal, surface disturbance and soil erosions after mining, sludge, oils, and greasy residues from the industries highly affect the soil and the land of nearby areas. These environmental hazards are not only effecting today’s generation but it can also deliberately add on the problems to the future coming generations.
Not only the streams and lands are being affected but the global climate has been changing as most urban areas of Asia, Africa and Latin American are facing high heat waves. In the larger cities the heat temperature is many degrees higher in the center than its surrounding environment. Due to the heat change many cities have to face air pollution because the air pollutants readily change their responses along with the heat stresses. The concept of environmentally stable urbanization can be achieved when the responsibilities of urban managerial departments and urban government are fulfilled properly. The urban government has several roles that can be categorized separately. Finance department, engineering works, development planning and development control, environmental health, public health, safety services, emergency services and administration (human resources) are all a part of stable and productive local government with respect to its environment and surroundings. These authorities for the roads, infrastructure of cities, building, duties and services have an important contribution in the critical aspects of urbanization which are persistent protection, pre disaster damage limitation, quick post disaster response and rebuilding.
Urbanism is referred as global phenomena because of many attractive factors. It can be considered as supreme reason of economic development in the world’s history. Migration leads to the extension of cities and sometimes city congestion. Hopes of high income opportunities, better lifestyle, and improvised facilities are few of the alluring elements that bring people to migrate towards the urban areas. The process of urbanization is not limited to any certain country; it has already acquired half of the world’s population and still leading with the pace to acquire the rest. The developed countries are heading towards post-urbanism and the developing countries are still doomed by the industrialization and residential settlement stages. Urbanization is quite a difficult as well as complex process which is nearly impossible to terminate. The hub of the major economical and developmental activities is ample cities of the country. Therefore, considering the proceeding nature of urbanism, it is important to explore such managerial processes that would minimize the impacts on environment as well as support the urbanization process.
In a developing country when urbanization takes place it brings along several adverse impacts apart from the favorable impacts. The ecosystems, streams, rivers, atmosphere, water resources, soil are being highly affected. Industrialization is causing a major portion of pollution. The direct emission of heat and inappropriate disposal of waste effluents negatively impact the natural environment. Urbanization is causing changeovers to the land for the commercial, industrial and social purposes. Even when the developmental project does not cover large area but it can still have greater impacts on the environment. Industries are not the only reason that contributes to the adverse effects to the environment. When the Industrial Revolution came into view, the global distribution of cities was already functionally present, and much of the environmental imbalance has been occurred. That shows the lack of management in the urban development regarding the environment. The rapid growth in the cities often resulted by the excessive immigration which leads to the rise of unemployed natives and slums.
Strong city planning management is essential to avoid the unsustainable societies there is a requirement of appropriate planning of cities and a responsible local and regional government. It cannot be denied that actions taken at a higher level will have pertinent results. Urban government and the supportive regulatory institutes have critical roles in the development of sustainable urbanization to achieve the eco-friendly objectives while maintaining the advances in urbanism. However, improvements can be achieved with the help of government interventions, new laws and policy formulation, specified expertise for the urban planning and zoning systems. The process of urbanism could be followed to establish such urban designs that call for urban revitalization. All the advances with help of policies and political support will ultimately encourage the urban development but with the minimum expense of the natural environment.