Rewilding lawns and gardens into miniature rainforestsMany scientists believe that halting global warming at 1.5°C will require us to invent Negative Emission Technologies – machines that can suck climate warming gases like carbon dioxide (CO₂) from the air. But such technology already exists and has done for over two billion years. From the trees outside your window to the microscopic algae in the ocean, nature is working hard to absorb the atmospheric carbon that is heating our world. Rather than reinvent the wheel, some experts are calling for natural solutions to climate change. These involve restoring natural habitats – such as forests and wetlands – which would draw down CO₂ through photosynthesis and store it as living tissue in plants. Rapidly phasing out greenhouse gas emissions is still vital, but letting nature do much of the hard work in removing the CO₂ that’s already in the atmosphere could save the time and money we’d need to develop artificial methods of capturing carbon. Returning many of the world’s ecosystems to something resembling their former glory could also help solve another crisis simultaneously. In this fourth issue of Imagine, we look at the mass extinction crisis that threatens the nearly nine million species on Earth and how radical action to prevent their extinction could also prevent ours. We asked experts to imagine how natural solutions to climate change could start at home and what a future with more of the wild in our lives might look like. In the end, it’s a case of saving two birds with one tree. You can view a web version of this issue here. (And don't miss out on the video at the end of this issue too.) Spread the word about climate action nowTake action. Forward this email or copy and share this link: A wilder world is a cooler worldNearly a million species are at risk of extinction without “transformative changes” to the way societies and economies are organised in the 21st century. That’s according to a report published in May 2019 by an international team studying Earth’s biodiversity. Climate change drives species to extinction and exacerbates threats such as habitat loss, by destroying the habitats themselves or changing the conditions that make them hospitable to different species. But it might surprise you to learn that across vast swathes of the world, nature is already returning to places where dense habitats were once destroyed by humans. Even on your own doorstep, your local environment could be wilder than it was 100 years ago. If you live in mainland Europe, that’s almost certainly the case. At a glance: Forests and wildlife are returning to Europe as farmland and villages are abandoned More and more people around the world are abandoning rural landscapes and moving to live in cities. In their absence, the land they once used for agriculture is regenerating as shrubland and forest. José M. Rey Benayas, a professor at the University of Alcalá, points out that forests returned at a rate of 2.2 million hectares per year between 2010-2015. Spain alone has tripled its forest area since 1900. These new habitats have ushered in wolves, brown bears, lynx and boar. "Populations of large carnivores such as the brown bear, the wolf, the Eurasian lynx and the wolverine have all increased in Europe. Populations of large and medium-sized herbivores, such as the red deer, the wild boar, the roe deer and the Iberian ibex, have also increased." José M. Rey Benayas 🌍 Rewilding: as farmland and villages are abandoned, forests, wolves and bears are returning to Europe In the UK, forests have recovered more slowly, from 5% of the land area after World War I to 13% today. Researchers estimate that every hectare of forest that’s restored in the UK could absorb the annual emissions of 30 London buses or 90 cars every year. Restoring forest cover in the UK to just 18% of the land area could absorb a quarter of the carbon that will need to be cut in order to reach net zero emissions by 2050. Aside from not emitting carbon in the first place, restoring forests across the world on an unprecedented scale could be our best bet for avoiding catastrophic climate change, according to a new study. Mark Maslin and Simon Lewis, two climate science professors at University College London, explain the thinking: Negative emissions: increasing the world’s forest land by one third – regrowing an extra billion hectares of trees over an area that’s roughly the size of the United States – could capture 205 billion tonnes of CO₂, according to the study. That’s about two thirds of man-made carbon emissions already in the atmosphere.
"Reforesting an area the size of the US will have massive benefits on local environments and will store a huge amount of man-made carbon emissions. It is not, however, a substitute for reducing those carbon emissions." Mark Maslin Simon Lewis Rewilding starts at homeReforesting the Earth will take decades, but right now, people in the UK could help bring back one of the country’s most diminished habitats in their own backyards. Since the end of World War II, Britain has lost 97% of its wild grassland – turned into farmland or dug up to build roads and homes. At a glance: this is how much of the UK’s lost grassland would have once looked Wild grassland in Transylvania (left) and Potwell Dykes in Nottinghamshire (right) What’s left is a sorry sight. The clipped lawns and neat grass verges of Britain mostly contain only one or two species of turf grass, compared to the more than 40 plant species that can thrive in a single square metre of grassland. As their native habitat has declined, British pollinating insects have vanished from a third of their range since 1980. Maintaining the hyper-manicured lawns that we’re used to seeing in public parks often involves petrol mowers and fertilisers which leak more carbon to the atmosphere during their production and use than the grass itself can store. If you have a lawn, you can think of it as your own patch of artificial grassland – a stunted remnant of a once vast ecosystem. But it needn’t be that way, says Adam Bates, an ecologist at Nottingham Trent University. There are four easy steps any gardener can follow to turn their lawn into a wildlife haven that locks away CO₂: 1. Cut higher Most lawn mowers have blades that are set as low to the ground as possible, ensuring that the lawn is cut to be flat and featureless, which is no good for wildlife. Bugs and small creatures need nooks and crannies to hide from predators. Spiders in particular need something to anchor their webs to. By adjusting the blade to the highest possible setting – often around 4 cm off the ground – mowing can leave taller grass with more recesses for insects to hide in. 2. Include mowing gaps Leaving longer gaps between mowing the lawn can give wildflower species the time they need to flower and provide nectar for pollinating insects to eat. By leaving a gap in spring, early flowering species like the native cowslip can bloom. Cowslip is a plant which has been declining for decades, but the Duke of Burgundy butterfly depends on it for somewhere to lay its eggs. Leaving a mowing gap in summer can give species like cat’s-ear and fox-and-cub (pictured) time to flower – both important food sources for leafcutter bees. 3. Don’t use fertilisers or herbicides You might expect herbicides to be a bad idea, but when it comes to lawns, fertilisers are only good for ensuring a luxuriant green colour – one or two grass species will soak up the extra nutrients and outcompete everything else. To ensure a rich variety of plants can thrive in your wildflower lawn, reducing the fertility of the soil is essential. 4. Remove the clippings By collecting the cut grass after you mow you can stop more nutrients getting into the soil and reduce the lawn’s fertility with every cut. If you’re 100% committed, you can leave strips at the sides or patches in the corners to go wild and form small wildflower meadows. Most wildflower seeds will be carried to your garden on the wind or by birds, but if you’re tired of waiting, you can buy and spread the seeds yourself. Once you’ve seen pockets of wildflower meadow spring up on your lawn, you may not want to stop there … "Grass – especially when not in flower – is the most aesthetically boring part of a grassland. The species that have traditionally been disregarded as “weeds” are far more interesting." Adam Bates 🌍 Four steps to make your lawn a wildlife haven – from green desert to miniature rainforest Ponds – the carbon sink in your backyardPollinator species would certainly benefit from more people turning their lawns into the wild grassland habitat that’s so rare in the British landscape today. But a single square metre of grassland might only absorb about 2-5g of CO₂ over the course of a year. So how helpful is rewilding your garden for slowing climate change? Very helpful, if you add a pond, says Mike Jeffries, an ecologist at Northumbria University. A pond that's only a square metre in size could suck as much as 247g of carbon from the air every year. Though small ponds make up a tiny proportion of the UK's land area – about 0.0006% of it – they punch well above their weight in terms of how much carbon they can bury as sediment. By digging a pond in your garden, you’d also be inviting some truly unique wildlife. Perhaps most interesting of all according to Jeffries is the tadpole shrimp (pictured) – thought to be the oldest animal in the world. "No longer overlooked, the importance of ponds in the carbon cycle and in fighting climate change is becoming apparent." Mike Jeffries 🌍 Ponds can absorb more carbon than woodland – here’s how they can fight climate change in your garden Half of all the UK’s ponds were lost during the 20th century, leaving many native amphibians searching for somewhere to live. As climate change threatens to dry up much of these habitats, garden ponds could provide an oasis for struggling species says Becky Thomas, an ecologist at Royal Holloway University:
Find out how to create your own garden pool here. Are you subscribed to Imagine?If you're not, join us now. Imagine is a newsletter that presents a vision of a world acting on climate change. It is produced by The Conversation, an independent source of news and views, sourced from the academic and research community and delivered direct to the public. A shared home for humans and wildlifeNo matter where you look, you’re likely to find a potentially useful habitat for nature that’s under threat. Brendan Wintle and Sarah Bekessy, two professors at University of Melbourne and RMIT University respectively, say that even very small patches can be invaluable for a particular species.
Moving out of gardens and into the streets, how could our towns and cities be reimagined with more space for nature? Heather Alberro, a political ecologist at Nottingham Trent University, believes that “urban greening” could make the places we live resilient to climate change and ensure a refuge for biodiversity:
At a glance: a tree’s canopy acts like a parasol, blocking out up to 90% of the sun’s radiation Source: Roland Ennos, Author provided
If all that sounds good to you then you’re in luck, Alberro says. Urban greening is being taken very seriously by architects, designers and politicians. You may find your neighbourhood growing wilder in the years to come:
If you live outside a major city then perhaps it's your daily commute that will change first. Thanks to efforts by campaigners and local councils in the UK, roadside verges are being turned into wildflower meadows, with an eight-mile “river of flowers” now hugging a motorway in Rotherham (pictured). According to Olivia Norfolk, an ecologist at Anglia Ruskin University, bees and butterflies don’t seem to mind the traffic and their numbers have “increased dramatically” where regular mowing has stopped and wildflower meadows have returned on grass verges. She said:
Seeing so much colour on land that was once devoid of life can really lift the spirits. Alberro believes this may be the greatest benefit from rewilding – more human happiness. The Japanese call it Shinrin-yoku, or “forest bathing” – the idea that regular immersion in nature is as good as therapy. In the future, people may not have to go too far to get their fix. "Evidence from a range of disciplines has uncovered numerous social, psychological, and health benefits of human exposure to green spaces. These include stress and anxiety reduction, improved cognitive functioning, lowered risks of depression, and overall greater mental and physical wellbeing." Heather Alberro 🌍 Urban greening can save species, cool warming cities, and make us happy More from The Conversation🌍 Can trees really cool our cities down? 🌍 National parks are beautiful, but austerity and inequality prevent many from enjoying them 🌍 How hyper-manicured public spaces hurt urban wildlife 🌍 Forget environmental doom and gloom – young people draw alternative visions of nature’s future Bonus video: how nature can save us from climate breakdown We give a voice to expertsClimate change is a crisis for civilisation. Evidence increasingly vindicates scientists’ warnings, yet the mainstream media largely fails to address it. By allowing other publishers and broadcasters free use of our evidence-based content, The Conversation helps them to improve their analysis. Help us make climate change a priority in newsrooms. Send us your views: Just hit reply and tell us how you found this issue. And let us if you have any more questions about cars of the future. Thanks to Marcus who reminded us of the need to include a link to the newsletter for sharing. Behind the scenes: This issue of Imagine was put together by Jack Marley (@J_E_Marley) in Newcastle-upon-Tyne and produced by Khalil A. Cassimally (@notscientific) at The Conversation UK's new headquarters in Euston, London. The role that natural solutions to climate change will play in the coming years is only starting to take shape. From restoring vast swathes of forest to sharing our cities with wildlife, our imaginations should run wild with the thought of what a world acting on climate change and biodiversity loss could look like. Coming up: In the next issue, we ask academics to imagine the future of work with respect to climate. Think four-day week for the climate, the role of automation … Image rights: Ariyaphol Jiwalak/Shutterstock (lead photo); Jörg Hempel/Wikimedia Commons (fox-and-cub); Repina Valeriya/Shutterstock (tadpole shrimp); Pictorial Meadows ('river of flowers' near Rotherham). |