What defines a city?
A city is a large human settlement, that depends on a series of systems such as housing, transportation, communication, sanitation and utilities. We can also call a city an urban development.
Urbanization has become a common special organisation of human activity worldwide, in developing countries but mostly in already developed countries (Deakin et al., 2007). In the past, hundreds of years ago, only a small amount of a nation’s population was living in the city, whereas nowadays we are noticing an average urbanisation rate of 70%. Due to geographical reasons, we are experiencing a major transition to urbanised life forms. But we cannot ignore the fact that at the same time we encounter a phenomenon of de-urbanization, or suburbanization, which does not affect at all the process of urbanization. This means that a percentage of the population would prefer living in the rural areas, for comfort or quietness some might say, but depending on the urban developments for most of their needs.
Living in the city has of course benefits and also disadvantages and this has to do to with a series of important roles: the shelter role, the religious role, the cultural role, the political role, the economic role, the social role, the engineering role and the network role (Deakin et al., 2007).
The Shelter Role means that a city is meant to offer different types of settlement configurations for a large number of people, based on the scale of the city and on the population number. A shelter is considered to be a human right and cities should be able to provide it for its population. Hence why cities are considered bringing a major contribution when it comes to sustainable human habitat (Deakin et al., 2007).
Even though cities were considered “the source of evil” in the past, nowadays they should provide a place for prayers for different types of religions.
The Cultural Role is represented by the historical footprint that some cities have, for example, cities where in the past, people have developed arts and science, such as Venice, Paris, Bologna, Prague, Amsterdam and many other places.
The Political Role is in link with the governance of the city, democracy having a big impact on the city structure. We find that political power and administrative functions are concentrated in the city, even though there was an unsuccessful attempt of de-concentration of government facilities in the past (Deakin et al., 2007).
The Economic Role is brought by the fact that a city is considered a large-scale marketplace, where most of the products are designed and manufactured, and also where there is a cycle of capital and goods that help in terms of city structure.
Due to housing a large number of populations, the social role focuses on the need of people to communicate with each other and to get together in different places.
The Engineering role is represented by technology, and the impact it has over a city. Obviously, in the current times, technology brings a major importance when it comes to development and future development (Deakin et al., 2007).
The network role states that cities are meant to communicate with each other, to work with each other in different ways, but more importantly in terms of economic, social and environmental.
What defines a sustainable city?
The concept of a sustainable city has a long history, firstly mentioned in 1987, when the World Commission on Environment and Development published “Our Common Future” under Gro Harlem Brundtland. The report defines sustainable development as “a development that meets the needs of the present without compromising the ability of future generations to meets their own needs” (WCED 1987, 43).
The next milestone when it comes to sustainable cities was in the United Nation Conference on Environment and Development in 1992, Rio de Janeiro, which focused on the notion of green and on the global issues that were not related to people or the actual city.
A sustainable city is considered to be more than an environmental benign city and should be also fulfilling economic and social goals. From an environmental point of view, urban sustainability played an important role in urban special configurations, for example, “the resourceful city”, “the garden city”, “the green city”, “the ecological city” and “the virtual city”. It is to be expected that the environmental quality can be impacted by urban growth, but not necessary, as with the modernisation of the city we have developed ways and methods for preserving the environment. The urban environment is considered a multi-faced phenomenon that varies from “hard pollution” to “quality of life” (Joss, 2015).
We can mention the fact that the urban environment is also thought to be accommodating many conflict interests, such as institutional, sectoral and geographical. Thus, we might call the sustainable city concept an interesting test for the “civitas notion” or for the civil society. The efficiency of achieving sustainability goals is majorly impacted by the ecological footprint of the city.
The sustainable city may be considered an evolving, experimental process, not a fixed entity or a specific outcome. This process is under a series of continuous questions, that are constantly rising issues along the way. Also, this field of study requires multiple research disciplines, each conceptualising urban sustainability in certain ways, and each pursuing particular interests. For example, environmental scientists started to analyse the city in terms of material flow: input and throughput of energy, building materials and water, and the outputs of pollution and waste. Obviously, the major concern and the desired outcome is to smartly use the resources that we have and to smartly reduce the amount of waste that we create (Joss, 2015).
Other major concerns when it comes to the sustainability of a city are planning issues and governance issues. This interdisciplinary social-scientific field is concerned with analysing urban policies, strategies and plans, with an influence from institutional and organisational structures, process and culture.
The sustainability of a city is based on three major factors, such as economic, social and environmental. This will be further expanded on to economic sustainability, social sustainability and environmental sustainability.
Later we found other increasingly recognised factors such as sustainable agriculture, sustainable tourism sustainable transport, sustainable regions and sustainable cities.
The Economic factor
The relationship between economic growth and the urban environment states that the bigger and wealthier a city gets, the more resources they consume and the more waste they create. With the economic growth, we encounter a lot of negative factors but also positive factors. For example, we have a bigger emission of carbon monoxide in cities rather than the rural settlements however we find that cities offer better conditions of living, such as drinkable water, increased sanitation, transportation and many others (Leitmann, 1999).
Of course, along with the growth of cities, we encounter more financial resources, technological resources and more human resources, these helping to solve most of the encountered issues that come with the rapid evolution of cities. With a wealthier and more educated population, solutions for improvement of the quality of living are very accessible and will come with a more dramatic impact.
The population of a city requires certain conditions for a good quality of life, such as water systems, sewage systems and a clean air that has a low percentage of pollutants (Leitmann, 1999).
The severity of urban environmental issues will be different from city to city, depending on the level of development. For example, the poorest cities will suffer when it comes to health and sanitation, not having the minimum level of living will result in an increased number of diseases and eventually deaths. In the meantime, cities that have developed further will have encountered the air pollution problem. (Leitmann, 1999).
Important environmental consequences are brought by the macroeconomic factors such as exchange, inflation, pricing and fiscal policies. These will influence in many ways the development of cities, they can influence the movement of goods, the construction of buildings, the consumption of land, the population growth and many more (Leitmann, 1999).
The Social Factor
Even though it comes less important than the economic or the environmental factors, the social sustainability factor includes social equity, health equity, community development, social capital, social support, human rights, labour rights, social responsibility, social justice, cultural competence, community resilience, human adaptation and few others (En.wikipedia.org, 2018).
Social Life, a UK-based social enterprise specialising in place-based innovations define social sustainability as "a process for creating sustainable, successful places that promote wellbeing, by understanding what people need from the places they live and work. Social sustainability combines the design of the physical realm with the design of the social world – infrastructure to support social and cultural life, social amenities, systems for citizen engagement and space for people and places to evolve." (En.wikipedia.org, 2018).