by
CNN
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Visions of the urban future typically revolve around mile-high skyscrapers, flying cars, and high-tech solutions to sustainability challenges.
But there is another vision that envisages a return to the wilderness on which cities were once built, complete 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 Rewilding movement.
Botanist Akira Miyawaki is one of the forefathers of this burgeoning effort after making an important discovery while studying Japanese vegetation in the 1970s. He noted that ancient, native forest ecosystems survived and thrived on unmanaged areas such as temples and cemeteries, while they had long since disappeared from cultivated lands.
Miyawaki began a program to restore Japan’s natural forestry practices at small sites across the country, using native soils and plants. In many cases, the results have been spectacular: rapid growth of dense and diverse ecosystems.
The “Miyawaki Method” has since become a global movement, with miniature forests guided by the botanist’s principles thriving in the US, Europe and Asia. They are also taking root in urban environments from Beirut to Bordeaux, playing a leading role in a movement that brings wild nature into the heart of cities.
One of the largest Miyawaki projects is led by the non-profit Institute for Environmental Education (IVN) in the Netherlands. His Tiny Forest program has planted more than 250 tennis court-sized lots in urban locations such as roadsides, commercial parks and schools.
“First it starts with choosing the site and trying to see what type of soil we are dealing with, what the water level is, what potential natural vegetation is present on the site,” says Daan Bleichrodt, head of tree planting at IVN. “You can do that by looking into the past to see what used to grow.”
Once the plants and trees have been seeded, there is minimal intervention. Over time, ecosystems develop that develop a life of their own. A study of 11 forests found more than 600 animal species and nearly 300 plant species “appearing naturally in the forests,” says Bleichrodt.
The forests serve as small carbon sinks, each absorbing an average of 127.5 kilograms of CO2 per year, according to the same study – equivalent to the emissions of an average car driven more than 300 miles – which could double as the forest matures.
They also provide a cooling effect. Researchers found that ground temperatures were up to 20 degrees Celsius lower than on nearby roads.
The concept of rewilding—broadly restoring native, natural ecosystems and processes—has flourished in rural areas, from the reintroduction of wolves in Yellowstone Park to ancient forestry in the Carpathian Mountains. Environmentalists believe the same principles can be applied to urban spaces.
Urban rewilding is an “approach that aims to increase ecological complexity in urban ecosystems with minimal to no long-term management intervention,” says Nathalie Pettorelli, senior scientist at the Zoological Society of London (ZSL) and lead author of her recent report, Rewilding Our Cities .
The report outlines a range of intervention options, from allowing wildlife to reclaim golf courses and development around railway infrastructure, to encouraging private vegetation and ending management of parks to allow natural processes to run wild. Measures “could also include active replanting and targeted species restoration measures.”
Potential benefits of restoring urban ecosystems could include building resilience to climate change, reducing pollution, reversing biodiversity loss and healthier local populations, says Pettorelli.
Urban rewilding is a “relatively new” movement, she says, pointing to a handful of cities that are taking bold steps in this direction. Singapore has established “supertrees” and green corridors harboring wild ecosystems, while three German cities are participating in a program to allocate land for wild habitats where they can grow freely.
A radical proposal to revitalize the English city of Nottingham would have transformed a run-down shopping center in the center into an urban oasis surrounded by woods and wild meadows. The council, with acclaimed architect Thomas Heatherwick, is pushing for an adapted vision for realigning the city around a vast ‘green heart’ that will allow the mall to be overgrown with flora.
London is also making ambitious moves through the Mayor’s London Rewilding Task Force, which supports dozens of separate but complementary programmes. Local authorities and activists have reintroduced beavers to the city for the first time in centuries, opened up new forest areas and created habitats for butterflies.
The next phase could include the conversion of managed grasslands to wild meadows, miles of green highways to benefit bees, butterflies and wildflowers, and the reintroduction of large herds of grazing animals to shape outer London ecosystems. But the vision is both bottom-up and top-down.
“As well as big (projects) that need big spaces, we also want to do more smaller actions across London’s doorstep,” says Shirley Rodrigues, Deputy Mayor for Environment. These include initiatives to map wildlife in local neighborhoods and identify species that should be prioritized for conservation.
Such plans aren’t a luxury, but sensible for a global city to pursue on multiple levels, says Rodrigues. “We know that rewilding can restore ecosystems and increase the diversity and abundance of different species in an area, but it also has a much wider role to play in making cities greener, healthier and more resilient to the effects of climate change health and well-being of Londoners,” she says.
The ZSL identified recurring challenges for urban rewilding projects. Larger initiatives will require public funds, which are scarce in difficult times. If wild plots are left unmanaged, there is a risk that invasive species will be introduced and negatively impact ecosystems.
Projects need to be supported by local people to be successful and avoid “green gentrification” that displaces people from target areas. Harmful practices such as the use of pesticides and artificial turf need to be tackled to allow rewilding. “We need tougher laws to stem the spread of activities that undermine efforts to restore urban nature,” says Pettorelli.
But the movement is gaining momentum. Bleichrodt lists complementary programs that work alongside the Tiny Forest project, such as: Tiny Forest has established a network in 10 countries from Curacao to Pakistan and focuses on raising awareness for new generations by working closely with local schools.
“I feel part of a larger movement trying to restore ecosystems,” says Bleichrodt. “An overgrown regeneration movement.”
