Realizing that we have failed to live in harmony with nature and by so doing weakened its ability to continue to provide, we need to find a way to undo the neglect of the past and plan towards restoration and a sustainable future. This academic review has to be brought nearer to our everyday life by looking to our cities – our homes. We need to ascertain if it is possible to create “green cities” that are ecologically sustainable and find out how to live in harmony with reasonable comfort.
A growing number of cities are showing symptoms of the global environmental
Figure 7.1: Natural systems were seldom incorporated in the design of our present-day cities.
crisis, ranging from a surge in respiratory ailments due to air pollution; illness due to drinking dirty water, socio-economic problems such as poverty, accumulation of garbage in the streets. This contributes to homeless street dwellers, theft, protest actions and social unrest. The modern city was supposed to be the pinnacle of human development but is ironically becoming the unhealthiest, stress-related, environment to live in.
Figure 7.2: Design trends of the past aimed at offering each resident his own secluded “paradise”
More than 55% of the world population today live in cities, implying that half the world population are deprived from the direct benefits gained from simply enjoying nature on their doorstep. The World Health Organization defines health as “a state of complete physical, mental, and social well-being and not merely the absence of disease and infirmity”. Nature deficit disorder refers to a hypothesis that human beings, especially children, show a wide range of behavioural problems due to spending less time outdoors. Direct contact with Nature satisfies the craving for authenticity, silence, peace, repose, and simplicity. It is therefore important that natural elements like clean water, air, and vegetation should form part of the design of a healthy city, allowing citizens to make use of the freely available ecosystem services of nature.
When urban planners in the past, were allocating land where development would not be allowed, it was nothing more a mathematical consideration. A specific number of ha were to be allocated per thousand people. The decision did not consider the value-added benefits that open spaces could offer in terms of improved social and emotional well-being of its citizens. As a result pockets of open space were “sacrificed” and randomly spread wherever buildings could not be built. So apart from open areas acting as isolated play lots for children, most often they are indeed literally nothing more than un-built “urban open space” without a designated purpose
The focus in some of our wealthy suburban parks is scenic beauty; planted with colourful exotic species with pruned hedges, colourful flowers, and neatly cut lawns. Their design is for aesthetic value. But due to the absence of indigenous plants, and the over-use of insecticides, they are ecologically sterile with little or no insect, bird, and animal life. So it would be fair to say that most of these city parks are only geared towards leisure and informal recreation. It has no ecological value.
Figure 7.3: Public spaces in up-market areas were often decorated with colorful exotic plants with no ecological consideration in mind.
Figure 7.4: Realizing the importance of ecological viability to encourage healthy living conditions, Town planners are providing public access to green open spaces in and around towns and cities
However as citizens are becoming more aware of the link between health and their environmental surroundings, town planners too are starting to cater for these needs. They are heeding the call of eco-conscious residents. In many towns and cities there is now a concerted effort to identify and preserve the natural systems where people can connect with green spaces within the cities but also with nature on the city outskirts and surrounding countryside. In so doing municipal authorities are looking for possible ways to sustain ecosystem services on their doorstep making the city environment sustainable and healthy for investing in the physical and psychological as well as social well-being of the residents.
The ideal of a planned residential community, where inhabitants can truly have a high quality of life was already envisioned in 1898 by the famous English town planner Ebenezer Howard. He promoted it in “Tomorrow: A Peaceful Path to Social Reform”. This was a visionary attempt to create “garden cities”. Today, more and more terminology such as “forest city,” “park city”, “urban greening”, “vertical forest city”, and “urban re-wilding”, is used amongst municipalities and urban planners. Proof that city dwellers have an inherent need to connect with nature is evident by the effort and time they spend to artificially create home gardens in pot-plants with small pets.
Open space also has financial value. Real estate values near parks are higher than others and people are prepared to invest here as they have an ingrained psychological and physical need for nature. Research shows that inner city residents have a 20% higher chance of suffering anxiety and an almost 40% greater likelihood of developing depression. Healthy parks are ideal places for stress-release and for socializing with friends and families Another useful function of urban open space is that it can serve as land dedicated to the production of food. Urban farming and urban forestry have been receiving much attention – especially in underprivileged townships. It makes sound investment sense to plant fruit trees and vegetables instead of flowers and lawns. The logical approach to urban open space planning should therefore be pragmatic in terms of Nature’s directives, preferring production or usefulness above aesthetics. In some of the world’s big cities community members ensure food security by utilizing vacant land for agricultural purposes. For example, in Hong Kong, 45% of vegetables, 68% of the chickens and 15% of the pigs used as food, are produced in the city. In Nairobi, 67% of the urban families are farmers and 25% of urban families in Kenya depend on self-produced food for survival. 65% of all families living in and around Moscow are farmers. In the USA, 30% of all agriculture is done within metropolitan areas. 60% of metropolitan Bangkok is used for agriculture.
Figure 7.5: Healthy parks are ideal places for stress release and for socializing with friends and family.
Figure 7.6: In cities where land is limited to cultivate, people are taking advantage of psace on roof-tops.
90% of the large cities in China are self-sufficient in the production of vegetables. 25% of the trees beautifying the streets of Bangalore, India, are fruit trees. In South Africa however, animal products such as meat, milk and eggs, vegetables and fruit which form the basic food of urban dwellers, are often produced on farms far from our cities; necessitating extra cost such as packaging and transport.
Figure 7.7: Stretches of land under power lines can serve as linkages between open spaces in towns and cities and the surrounding nature.
But the ideal of ecological viable cities requires much more than simply “greening”. Often attempts at greening are only limited representatives of real nature, for example having pot plants mainly for the purpose of decoration. Harmony between city-dwellers and nature is not to be reached by merely planting of trees nor even putting aside some dispersed pockets of natural open space where buildings are not possible. This is where the development of a Metropolitan Open Space System (MOSS) poses great hope for creating truly sustainable open spaces in cities.
Figure 7.8: Indigenous biodiversity surrounding the town or city is more likely to move into the settlement if it supports the same vegetation.
The larger the area of a park or reserve, the better chances it has to be ecological viable. In isolated urban open spaces, there will be too many missing links or organisms to accommodate ecologically balanced food chains. Therefore, an ideal MOSS must be a system where various open spaces are linked to each other and where they are kept as near as possible to natural functioning pieces of nature. Rivers and linear ridges are ideal linkages connecting urban parks. Examples of green areas that need to be connected with parks are stretches of nature under power lines, botanical gardens and cemeteries and broad road verges. Some municipalities even build ‘wildlife bridges’ to ensure safe passage for wildlife over busy highways.
Figure 7.9: Natural systems were seldom incorporated in the design of our present-day cities.
Figure 7.10: Canals made of concrete does not support natural ecosystems.
The more an open space system retains remnants of the original surrounding countryside with its indigenous vegetation and wildlife, the easier it would be for indigenous biodiversity to make it their home. With abundant bird, animal and insect life, food chains will remain functional within self-sustaining ecosystems. Therefore, it is important that spatial links should connect fragments of nature, enhancing movement of species along connecting corridors. This enhances the chances of survival of animal life in towns and cities.
Owls and birds like the sparrow and rock pigeon have adapted remarkably well to the urban ecosystem. Frogs, bats, and moles are common in cities. The basic foods of these animals are small rodents and insects, etc., which often cause great damage to gardens. For the purpose of pest control and the maintenance of biodiversity, these animals offer a crucial service and could play a vital role in the urban ecosystem.
Figure 7.11: For open spaces to be ecologically functional it should allow natural processes opposed to intensive maintenance and grooming.
Other ecological services that open spaces offer include the cooling of urban temperatures where trees provide shade. Surfaces consisting of groundcover and vegetation will ensure ground water recharge. Parks hosting unspoilt wetlands and marsh vegetation will clean effluent from the water and ensure flood retention. But concrete paving and other hard surfaces cause rainfall to run off without penetrating the soil. And as the rainwater is rapidly being flushed far away to distant reservoirs, it must again be pumped back all the way for domestic use. Even our remaining city streams and dams are often so polluted that aquatic life is seldom present. Instead of constructing cement channels whereby water is removed from the city, these valleys should be kept natural and it can also serve as corridors for safe cycling and pedestrian movement. It will create an atmosphere of health and wellbeing.
Adding insult to injury, a big part of municipal budgets is allocated to the maintenance of city parks and open spaces. It involves services such as the application of expensive fertilizers and herbicides, irrigation and the regular mowing of lawns, the trimming and manicuring of hedges, the spraying of insecticides, and the planting of colourful flowers. It would make far better sense to keep parks in line with natural processes. In water-scarce countries the luxury of planting thirsty vegetation requiring lots of purified water is unsustainable.
Figure 7.12: We as humans need to rekindle our connection with nature.
Instead of applying expensive artificial fertilizers, manufactured at great environmental cost, one should rather plough back Nature’s own system of fertilizing by leaving fallen leaves to return to the soil. But instead we have it collected and removed at great cost, transported in already congested traffic lanes, adding to air pollution, to overloaded dumping sites where its potential is completely wasted. Instead of encouraging dynamic living systems to establish itself we have been eradicating insect and bird life with chemicals. When interacting elements such as insects, amphibians and birds are missing in city parks and open spaces, we can refer to them as “cosmetic green ecological deserts”.
Figure 7.13: The more materials in a city are recycled or re-used, the more sustainable it becomes.
The process of connecting and preserving green spaces in a city to make it more ecologically viable is only part of the answer to live sustainably. In the previous chapters we saw how all matter circulates in a natural ecosystem. We saw how stagnation equals death of the system. Therefore, our model for an ideal city is that of an artificial ecosystem that functions as near as possible to a self-sustaining natural one. It should be a system that is able to recycle matter without harming the system itself. It minimizes the extraction of matter in the form of resource.
It follows that if the goal of a sustainable city where its inhabitants can enjoy a productive, healthy, peaceful, relaxing livelihood is to be attained, we will have to
find ways in which the dependable ecological guidelines, laid down by Nature, can be implemented. Such design should include the holistic an integrated approach whereby the social welfare of its citizens and environmental quality as well as the economic functions are all included into a coherent dynamic functioning system.
A sustainable city requires that it should be as far as possible self-providing in terms of produce, and with minimum output of pollution and waste. Therefore, there should be as little as possible input from outside the city. Energy input should be localized from renewable resources such as the sun (solar), wind, geothermal and small modular nuclear reactors. The need for fossil fuels (coal, petrol and oil and natural gas) should be reserved for long-distance mass transport (shipping and airfreight) and heavy industry like mining and the manufacturing of steel and cement.
Figure 7.14: Renewable wind and solar energy will replace coal and gas for domestic use and light industry
To limit import from external sources, material production of necessities should be created within the city. A circular system should be adopted opposed to the linear system of make – use – discard. Products should be re-circulated with no pollution or excess “throw away” of matter. To the principle action of Recycling, should be added that of Re-use, Repair and Reduction of the manufacturing of unnecessary items as far as possible. We could also add actions like Repair before simply throwing it away.
Figure 7.15: The mentality of recycling should also inform our decisions related to water consumption and organic waste
The mentality of Recycling should also inform our decisions related to water consumption and organic waste. For example, the importation of water can be drastically reduced if we harvest rainwater from roofs and other hard surfaces. The harvested water can be used to irrigate our parks, gardens and for washing cars.. Also, the leaves and grass cuttings should be composted as well as kitchen waste, instead of using manufactured fertilizers. This also reduces the need for municipal dumping sites that create water pollution and unsightly sites.
Figure 7.16: In a sustainable city the user fossil fuel resources for individual transport will be something of the past
If these measures are implemented successfully in a town or city, the settlement will have ecological value. We will experience reduced air, water and noise pollution and increased ecological diversity. If we compare it to nature, the functioning of cities should therefore be managed like nature manages itself in terms of trophic levels that enable a circular, dynamically controlled, open ecosystem. Local inner city food supply should be encouraged. This will form the T1 trophic level. People will occupy the higher trophic levels of herbivores (T2) as well as carnivores (T3 and 4). If food production in the city is to be successful, T5 level its soil with its natural bacteria should be carefully managed.
In terms of its social benefit, we will experience improved quality of life. An increase in both real and perceived security and safety will promote social equality and stability. Increased social integration will facilitate co-operation and cohesion encouraging increased cultural vitality and civic pride.
As social welfare and environmental quality often goes hand-in-hand, the Metropolis of Lyon in 2022 launched the construction of a Charter for Public Spaces. It envisions the development spaces for movement and gathering by integrating squares, parks and streets with unspoilt natural elements. It is believed that this will result in reduced public expenditure on health and urban management, higher property prices, increased business confidence and by so doing attract human capital.
It strives to enhance the value of unspoilt nature to citizens in terms of reduced public expenditure on health and urban management, attracting human capital and increased business confidence. And in terms of its social benefit, it offers improved quality of life, an increase in both real and perceived security and safety, the promotion of social equality and stability, increased cultural vitality, social integration and civic pride.
We should encourage town-planners to create and connect sustainable pieces of nature in our cities and towns.
Figure 7.17: Social welfare and environmental quality often goes hand in hand
It will greatly improve our living environment and help us to be more in touch with nature. A healthy respect for all living things should result in more people adopting an eco-friendly mindset. We would think twice of the kind of products we use and how we dispose of it. We will consider the means of transport we use, and the methods of generating energy. Then hopefully we could start to slow down the vicious circle of environmental destruction as a result of ill-considered economic and industrial practices.
Because of our ability to influence the environment in such a big way human beings are called the “ecologically dominant”. We can create a sustainable life if we want to. The time to act is now. If you want to predict the future, create it!