The growth and development of cities is a prerequisite for economic growth. The urbanization trend continues worldwide. By 2050, 2/3rds of all people on the planet would be living in urbanised areas. Urbanization offers enough economic gains. Worker productivity and worker learning are the two short term and long-term benefits of cities. Cities also act as centres of innovation. According to research, the current economic model driving the world today is not sustainable. It is also a widely recognized fact that resource limitations cause unstable economic growth. This needs for a new approach to economic development where ecosystems become the underpinning foundations. Natural resources are economic assets whether or not they enter the marketplace.
Cities are favourite human habitats .Needless to say, as and when they grow, they parasitize more and more upon their adjacent landscape. The consuming city and the productive landscape need to be integrated for sustainable development and cities need to become positive contributors to the ecosystem.
The unplanned and explosive growth of the urban mass, leads us to question the scheduled end of fossil fuels and, more broadly, the limited availability of resources. The concern areas not only include conservation of energy, water, wastes or raw materials but also social and generational cohesion in these urban habitats.
Emission of Carbon dioxide and other greenhouse gases has led to a global warming of 0.85% .Observed warming is responsible for ¾ of the daily heat extremes around the world and increase in 1/5 of its rainfall .This adversely affects and impacts both the Macro and Micro ecosystems. According to the World Resources Institute, India stands fourth among the top ten emitters of GHG(Green House Gases).China holds the number 1 position, followed by US, and EU. India’s emission levels in percentage stands at 6.96 while China‘s is at 25.26.(Source-World Resources Institute)
The concept of a symbiotic city is based on the reduction of the city’s needs by increasing its intrinsic efficiency, on the systematic integration of renewable sources and on the establishment of urban symbioses. The English meaning of symbiosis is any relationship between two individuals where both the individuals benefit. A win win combination. For transforming cities from a parasitic constitution to one of symbiotic, regenerative one, a rational research based approach is obligatory.
“A Symbiotic City has mutually beneficial relationships with its macro and micro ecosystems. It produces ecosystem services that are equal or greater than its net use of those services. The transition to a symbiotic city requires a cultural and economic recognition that we are embedded in and dependent upon our ecosystems. A symbiotic city enhances the natural environment, sustainable economic activity, and quality of life.”(Based on definition by Future Proofing Cities Working Group, July 2012)
The Macro ecosystem includes lakes, oceans, forests, mountains, deserts, and swamps. Micro ecosystems occur within the macro ecosystems. It is defined by the diversity of species, which exists within the temperature patterns, soil compositions moisture levels, altitude, and sunlight exposure. Both the macro and micro ecosystems together makeup the biodiversity.
There are several factors to be considered while developing a symbiotic city.
Two factors of the below, are considered for this article.
1. Zero carbon-energy
2. Ecosystem Service Infrastructure
3. Urban Food production
4. High-density, Complete Community Planning
5. Regenerative Building Fabric Transformation
6. Infinite Material and Resource Recycling
7. Socio-Economic Transformation
The methodology for this article is qualitative content analysis of articles which have been sourced from the internet. Reference has been made of the websites referred to.
1. Zero Carbon energy
Climate change is the biggest challenge faced by humankind and our ecosystem today .Greenhouse gas emissions continue to increase throughout the world. The most often quoted source of greenhouse gas emissions is the burning of fossil fuels. A greenhouse gas is any gaseous compound in the atmosphere that is capable of absorbing infrared radiation, thereby trapping and holding heat in the atmosphere. By increasing the heat in the atmosphere, greenhouse gases are responsible for the greenhouseeffect, which ultimately leads to global warming. China and India with their explosive population growth, contribute to the increase of greenhouse gases in the atmosphere. Therefore, developing and deploying fossil-fuel-free and carbon-neutral energy sources that will allow us to meet and exceed the greenhouse gas reduction is essential to avoid ecosystem disruptions and breakdowns. For this shifting from a fossil fuel based economy to zero-carbon fuel based economy is required. Moving to a nuclear energy based economy is a possible solution to this problem. (Thorium nuclear power generation) Solar, wind and hydropower are the other alternatives to fossil fuels. Practical policy that encourages and motivate transformational shift from a fossil fuel to a zero-carbon fuel economy is required in the Ecosystem services.
2. Ecosystem Service Infrastructure
Ecosystem services are the byproducts of natural ecological processes produced by healthy ecosystems which offer all of the necessary biological settings for our existence.
The following constitute an ecosystem service infrastructure: Oxygen production, Drinking water production and filtration; Reduction of pathogens and pollutants; Waste absorption; Storm and flood protection; Natural storm water protection; Biodiversity preservation; Pollination; Nutrient regulation; Increased production of fish, shellfish, timber, and other food and raw materials; Erosion control; Biodiversity; Aesthetic value (beauty);Recreational opportunities for fishing, hunting, boating, hiking, bird watching, and educational and scientific benefits.
Physical infrastructure that is either natural or manmade sustains the formation of natural ecosystems within cities.
The ecosystem services within the urban context are:
Urban forestswhich are a forestor a collection of trees that grows within a city, town or a suburb. In a wider sense it may include any kind of woody plant vegetation growing in and around human settlement.
Natural and engineered wetlands; A natural wetland catches and treats runoff for less cost than most other methods. Wetlands provide an alternative to septic tanks and leach fields. Constructed wetlands perform many of the functions of a natural wetland.
Watercourseswhich are rivers, streams and canals
Green roofs, green walls and facades; Green façades are systems in which vines and climbing plants or cascading groundcovers grow into supporting structures that are purposely designed for their location.