Dubai, United Arab Emirates (CNN) — Visions of the urban future tend to focus on mile-high skyscrapers, flying cars and high-tech solutions to address sustainability challenges.
But another vision predicts a return to the wilderness on which cities were once built, with forests and wild animals long lost.
This vision is beginning to materialize in major cities around the world in the form of the urban renewal movement.
Among the forerunners of this nascent effort is botanist Akira Miyawaki, who made an important discovery while researching Japanese vegetation in the 1970s. He noted that ancient native forest ecosystems survive and thrive on uncultivated plots of land such as temples and tombs, while on cultivated plots they have long since disappeared.
Miyawaki set up a program to restore Japan’s natural forests on small sites around the country using native soil and plants.
In many cases the results have been astonishing: the rapid growth of dense and diverse ecosystems.
Since then, the Miyawaki method has become a global movement, with miniature forests, guided by the principles of the botanical world, flourishing across the United States, Europe and Asia.
Microforests also shape urban environments from Beirut to Bordeaux, playing a leading role in a movement to bring wild nature into the heart of cities.
The non-profit Institute for Environmental Education (IVN) in the Netherlands is leading one of Miyawaki’s biggest projects. His scheme, called Tiny Forest, has more than 250 tennis court-sized plots of land in urban locations such as roads, parks and schools.
“We first start by selecting the site and trying to figure out what kind of soil we’re dealing with, what water level is needed and what the natural vegetation is likely to be on the site,” says Dan Bleichrodt, Head of Arboriculture at IVN.
“You can do this by looking into the past, to see what used to grow here,” he explains.
Over time, ecosystems develop that take on the form of a life of their own.
One study of 11 forests found that more than 600 animal species and about 300 plant species “arising on their own in the forests,” according to Bleichrodt.
Forests act as small carbon sinks, each capturing an average of 127.5 kilograms of carbon dioxide per year – according to the same study – equivalent to the emissions from driving a regular car for more than 300 miles.
The forests also provide a cooling effect, as the researchers found that ground temperatures were 20 degrees Celsius lower than in nearby streets.
Resilience in the face of climate change
The concept of rewilding, meaning the restoration of ecosystems and native and natural processes, has flourished in rural areas, from the reintroduction of wolves to Yellowstone Park and the planting of ancient forests in the Carpathian Mountains.
Environmentalists believe the same principles can be applied to urban spaces.
Urban regeneration is “an approach that aims to increase ecological complexity in urban ecosystems with minimal or no long-term management intervention,” according to Natalie Pettorelli, senior scientist at the Zoological Society of London (ZSL) and lead author of the latest report Entitled “Rebuilding our cities”.
The report identifies a range of possibilities for interventions, from allowing wildlife to restore golf courses and developing rail infrastructure, to improving private vegetation and ending park management to allow natural processes to run wild.
Measures may also include active replanting and targeted species recovery efforts.
As for potential benefits of restoring urban ecosystems, they could include improving resilience to climate change, reducing pollution, reversing biodiversity loss and improving the health of resident populations, Petrelli says.
Urban renewal is a “relatively new” movement, Petorelli says, noting that few cities are taking bold steps in this direction.
Singapore has installed “Supertrees” and green corridors to accommodate terrestrial ecosystems, and green corridors to accommodate terrestrial ecosystems, while three German cities are participating in a scheme to allocate spaces for wild habitats to grow freely.
The radical proposal to revitalize the English city of Nottingham has transformed a dilapidated shopping center into an urban oasis surrounded by woodland and wild pastures. The local council is pushing ahead with a revised vision, by renowned architect Thomas Heatherwick, to reorient the town around an expansive ‘green heart’ which will allow the shopping center to grow with vegetation.
London is also taking ambitious steps through the Mayor’s Rebuilding Task Force, which supports dozens of separate and complementary schemes.
Local authorities and environmental activists reintroduced beavers to the city for the first time in centuries, developed new forests and created habitats for butterflies.
The next phase could include turning managed grasslands into wild pastures, miles of green highways for bees, butterflies and wildflowers, and reintroducing large herds of grazing animals to form ecosystems outside London.
However, the Zoological Society of London has identified recurring challenges facing urban regeneration projects, as larger initiatives will require public funding, which is scarce during the current turbulent times. Leaving wild areas unattended can lead to the introduction of invasive species and have a negative impact on ecosystems.
Projects must win the support of the local population to thrive and avoid “green gentrification” that displaces people from the target areas. Harmful practices such as the use of pesticides and artificial lawns must be addressed to give reforestation a chance.