12 best ways to get cars out of cities – ranked by new research

Kimberly Nicholas– Associate Professor of Sustainability Science, Lund University

A stretch of the Champs-Élysées around the Arc de Triomphe in Paris is due to be pedestrianised by 2030. Shutterstock

Question: what do the following statistics have in common?

Answer: the vehicles on our streets, primarily the not-so-humble passenger car.

Despite the (slow) migration to electric-powered cars, consumer trends are making driving even more wasteful and unequal. A recent analysis found the emissions saved from electric cars have been more than cancelled out by the increase in gas-guzzling Sport Utility Vehicles (SUVs). Around the world, SUVs alone emit more carbon pollution than Canada or Germany, and are causing a bigger increase in climate pollution than heavy industry.

While cars are sometimes necessary for people’s mobility and social inclusion needs – not least those with disabilities – car-centric cities particularly disadvantage the already-marginalised. In the UK, women, young and older people, those from minority communities and disabled people are concentrated in the lowest-income households, of which 40% do not have a car. In contrast, nearly 90% of the highest-income households own at least one car.

So the driving habits of a minority impose high costs on society, and this is especially true in cities. Copenhagen, for example, has calculated that whereas each kilometre cycled benefits society to the tune of €0.64 (53 pence), each kilometre driven incurs a net loss of -€0.71 (-59p), when impacts on individual wellbeing (physical and mental health, accidents, traffic) and the environment (climate, air and noise pollution) are accounted for. So each kilometre travelled where a car is replaced by a bicycle generates €1.35 (£1.12) of social benefits – of which only a few cents would be saved by switching from a fossil-fuelled to an electric-powered car, according to this analysis.

Reducing car use in cities

Half a century ago, the Danish capital was dominated by cars. But following grassroots campaigns to change policies and streets, including replacing car parking with safe, separated bike lanes, Copenhagen has increased its biking share of all trips from 10% in 1970 to 35% today. In 2016, for the first time, more bicycles than cars made journeys around the city over the course of that year.

View of central Copenhagen, Denmark
Bicycles rule the centre of Copenhagen following campaigns to replace parking with safe bike lanes. Shutterstock

But while many other car-limiting initiatives have been attempted around the world, city officials, planners and citizens still do not have a clear, evidence-based way to reduce car use in cities. Our latest research, carried out with Paula Kuss at the Lund University Centre for Sustainability Studies and published in Case Studies on Transport Policy, seeks to address this by quantifying the effectiveness of different initiatives to reduce urban car use.

Our study ranks the 12 most effective measures that European cities have introduced in recent decades, based on real-world data on innovations ranging from the “carrot” of bike and walk-to-work schemes to the “stick” of removing free parking. The ranking reflects cities’ successes not only in terms of measurable reductions in car use, but in achieving improved quality of life and sustainable mobility for their residents.

In all, we have screened nearly 800 peer-reviewed reports and case studies from throughout Europe, published since 2010, seeking those that quantified where and how cities had successfully reduced car use. The most effective measures, according to our review, are introducing a congestion charge, which reduces urban car levels by anywhere from 12% to 33%, and creating car-free streets and separated bike lanes, which has been found to lower car use in city centres by up to 20%. Our full ranking of the top 12 car-reducing measures is summarised in this table:

The inequality of car use

Cars are inherently inefficient and inequitable in their use of land and resources. On average, they spend 96% of their time parked, taking up valuable urban space that could be put to more beneficial uses such as housing and public parks. In Berlin, car users on average take up 3.5 times more public space than non-car users, primarily through on-street parking.

And it is overwhelmingly richer people who drive the most: in Europe, the top 1% by income drive nearly four times more than the median driver, accounting for some 21% of their personal climate footprint. For these highest emitters, climate pollution from driving is second only to flying (which, on average, generates twice as many emissions).

Prioritising cars as a means of transport also favours suburban sprawl. City suburbs typically possess larger homes that generate higher levels of consumption and energy use. North American suburban households consistently have higher carbon footprints than urban ones: one study in Toronto found suburban footprints were twice as high.

It’s also clear that road traffic levels swell to fill the size of the roads built – yet traffic planning routinely ignores the fact that this “induced demand” exaggerates the benefits and underestimates the costs of building more roads.

Read more: We transformed a London borough into a game to get fewer people travelling by car — here’s what happened

Electric vehicles are necessary, but they’re not a panacea. Since cars tend to be on the road for a long time, the migration to electric vehicles is very slow. Some studies anticipate relatively small emissions reductions over the coming decade as a result of electric vehicle uptake. And even if there’s nothing damaging released from an electric car’s exhaust pipe, the wear of car brakes and tyres still creates toxic dust and microplastic pollution. However a car is powered, can it ever be an efficient use of resources and space to spend up to 95% of that energy moving the weight of the vehicle itself, rather than its passengers and goods?

COVID-19: a missed opportunity?

Our study assesses urban mobility innovations and experiments introduced before the pandemic was declared. In response to COVID-19, travel habits (to begin with, at least) changed dramatically. But following large reductions in driving during the spring of 2020, road use and the associated levels of climate pollution have since rebounded to near pre-pandemic levels. Indeed, in Sweden, while public transport use declined by around 42% during the first year of the pandemic, car travel declined by only 7% in the same period, leading to an overall increase in the proportion of car use.

Commuter traffic in Stockholm
Commuter traffic in Stockholm in November 2021. Sweden has seen an overall increase in its proportion of car use during the pandemic. Shutterstock

While entrenched habits such as car commuting are hard to shift, times of disruption can offer an effective moment to change mobility behaviour – in part because people forced to try a new habit may discover it has unexpected advantages. For such behaviour to stick, however, also requires changes in the physical infrastructure of cities. Unfortunately, while European cities that added pop-up bike lanes during the pandemic increased cycling rates by a stunning 11-48%, we are now seeing a return to car-centric cities, with extra car lanes and parking spaces once again displacing cycle lanes and space for pedestrians.

Overall, the opportunities to align pandemic recovery measures with climate targets have largely been squandered. Less than 20% of government spending on pandemic measures globally were likely to also reduce greenhouse gas emissions.

The extent to which workers resume driving to their offices is another key issue determining future car use in cities. Thoughtful travel policies to reduce unnecessary travel, and opportunities for faraway participants to fully participate in meetings and conferences digitally, could slash emissions by up to 94% – and save time to boot. Those who work remotely three or more days per week travel less overall than their peers. But long car commutes can quickly wipe out such emissions savings, so living close to work is still the best option.

No silver bullet solution

The research is clear: to improve health outcomes, meet climate targets and create more liveable cities, reducing car use should be an urgent priority. Yet many governments in the US and Europe continue to heavily subsidise driving through a combination of incentives such as subsidies for fossil fuel production, tax allowances for commuting by car, and incentives for company cars that promote driving over other means of transport. Essentially, such measures pay polluters while imposing the social costs on wider society.

City leaders have a wider range of policy instruments at their disposal than some might realise – from economic instruments such as charges and subsidies, to behavioural ones like providing feedback comparing individuals’ travel decisions with their peers’. Our study found that more than 75% of the urban innovations that have successfully reduced car use were led by a local city government – and in particular, those that have proved most effective, such as congestion charges, parking and traffic controls, and limited traffic zones.

But an important insight from our study is that narrow policies don’t seem to be as effective – there is no “silver bullet” solution. The most successful cities typically combine a few different policy instruments, including both carrots that encourage more sustainable travel choices, and sticks that charge for, or restrict, driving and parking.

Illustration: Emma Li Johansson, LiLustrations, Author provided

So here are the 12 best ways to reduce city car use:

1. Congestion charges

The most effective measure identified by our research entails drivers paying to enter the city centre, with the revenues generated going towards alternative means of sustainable transport. London, an early pioneer of this strategy, has reduced city centre traffic by a whopping 33% since the charge’s introduction by the city’s first elected mayor, Ken Livingstone, in February 2003. The fixed-charge fee (with exemptions for certain groups and vehicles) has been raised over time, from an initial £5 per day up to £15 since June 2020. Importantly, 80% of the revenues raised are used for public transport investments.

Other European cities have followed suit, adopting similar schemes after referenda in Milan, Stockholm and Gothenburg – with the Swedish cities varying their pricing by day and time. But despite congestion charges clearly leading to a significant and sustained reduction of car use and traffic volume, they cannot by themselves entirely eliminate the problem of congestion, which persists while the incentives and infrastructure favouring car use remain.

2. Parking and traffic controls

In a number of European cities, regulations to remove parking spaces and alter traffic routes – in many cases, replacing the space formerly dedicated to cars with car-free streets, bike lanes and walkways – has proved highly successful. For example, Oslo’s replacement of parking spaces with walkable car-free streets and bike lanes was found to have reduced car usage in the centre of the Norwegian capital by up to 19%.

3. Limited traffic zones

Rome, traditionally one of Europe’s most congested cities, has shifted the balance towards greater use of public transport by restricting car entry to its centre at certain times of day to residents only, plus those who pay an annual fee. This policy has reduced car traffic in the Italian capital by 20% during the restricted hours, and 10% even during unrestricted hours when all cars can visit the centre. The violation fines are used to finance Rome’s public transport system.

4. Mobility services for commuters

The most effective carrot-only measure identified by our review is a campaign to provide mobility services for commuters in the Dutch city of Utrecht. Local government and private companies collaborated to provide free public transport passes to employees, combined with a private shuttle bus to connect transit stops with workplaces. This programme, promoted through a marketing and communication plan, was found to have achieved a 37% reduction in the share of commuters travelling into the city centre by car.

5. Workplace parking charges

Another effective means of reducing the number of car commuters is to introduce workplace parking charges. For example, a large medical centre in the Dutch port city of Rotterdam achieved a 20-25% reduction in employee car commutes through a scheme that charged employees to park outside their offices, while also offering them the chance to “cash out” their parking spaces and use public transport instead. This scheme was found to be around three times more effective than a more extensive programme in the UK city of Nottingham, which applied a workplace parking charge to all major city employers possessing more than ten parking spaces. The revenue raised went towards supporting the Midlands city’s public transport network, including expansion of a tram line.

Norwich city centre, Norfolk.
Norwich reduced car commuters by nearly 20% with its workplace travel plan, including swapping car for bike parking. Shutterstock

6. Workplace travel planning

Programmes providing company-wide travel strategies and advice to encourage employees to end their car commutes have been widely used in cities across Europe. A major study, published in 2010, assessing 20 cities across the UK found an average of 18% of commuters switched from car to another mode after a full range of measures were combined – including company shuttle buses, discounts for public transport and improved bike infrastructure – as well as reduced parking provision. In a different programme, Norwich achieved near-identical rates by adopting a comprehensive plan but without the discounts for public transport. These carrot-and-stick efforts appear to have been more effective than Brighton & Hove’s carrot-only approach of providing plans and infrastructure such as workplace bicycle storage, which saw a 3% shift away from car use.

7. University travel planning

Similarly, university travel programmes often combine the carrot of promotion of public transport and active travel with the stick of parking management on campus. The most successful example highlighted in our review was achieved by the University of Bristol, which reduced car use among its staff by 27% while providing them with improved bike infrastructure and public transport discounts. A more ambitious programme in the Spanish city of San Sebastián targeted both staff and students at Universidad del País Vasco. Although it achieved a more modest reduction rate of 7.2%, the absolute reduction in car use was still substantial from the entire population of university commuters.

8. Mobility services for universities

The Sicilian city of Catania used a carrot-only approach for its students. By offering them a free public transport pass and providing shuttle connections to campus, the city was found to have achieved a 24% decrease in the share of students commuting by car.

Catania, Sicily
Catania achieved a 24% decrease in the share of students commuting by car. Shutterstock

9. Car sharing

Perhaps surprisingly, car sharing turns out to be a somewhat divisive measure for reducing car use in cities, according to our analysis. Such schemes, where members can easily rent a nearby vehicle for a few hours, have showed promising results in Bremen, Germany and Genoa, Italy, with each shared car replacing between 12 and 15 private vehicles, on average. Their approach included increasing the number of shared cars and stations, and integrating them with residential areas, public transport and bike infrastructure.

Both schemes also provided car sharing for employees and ran awareness-raising campaigns. But other studies point to a risk that car sharing may, in fact, induce previously car-free residents to increase their car use. We therefore recommend more research into how to design car sharing programmes that truly reduce overall car use.

10. School travel planning

Two English cities, Brighton & Hove and Norwich, have used (and assessed) the carrot-only measure of school travel planning: providing trip advice, planning and even events for students and parents to encourage them to walk, bike or carpool to school, along with providing improved bike infrastructure in their cities. Norwich found it was able to reduce the share of car use for school trips by 10.9%, using this approach, while Brighton’s analysis found the impact was about half that much.

11. Personalised travel plans

Many cities have experimented with personal travel analysis and plans for individual residents, including Marseille in France, Munich in Germany, Maastricht in the Netherlands and San Sebastián in Spain. These programmes – providing journey advice and planning for city residents to walk, bike or use (sometimes discounted) public transport – are found to have achieved modest-sounding reductions of 6-12%. However, since they encompass all residents of a city, as opposed to smaller populations of, say, commuters to school or the workplace, these approaches can still play a valuable role in reducing car use overall. (San Sebastián introduced both university and personalised travel planning in parallel, which is likely to have reduced car use further than either in isolation.)

12. Apps for sustainable mobility

Mobile phone technology has a growing role in strategies to reduce car use. The Italian city of Bologna, for example, developed an app for people and teams of employees from participating companies to track their mobility. Participants competed to gain points for walking, biking and using public transport, with local businesses offering these app users rewards for achieving points goals.

There is great interest in such gamification of sustainable mobility – and at first glance, the data from the Bologna app looks striking. An impressive 73% of users reported using their car “less”. But unlike other studies which measure the number or distance of car trips, it is not possible to calculate the reduction of distance travelled or emissions from this data, so the overall effectiveness is unclear. For example, skipping one short car trip and skipping a year of long driving commutes both count as driving “less”.

While mobility data from apps can offer valuable tools for improved transport planning and services, good design is needed to ensure that “smart” solutions actually decrease emissions and promote sustainable transport, because the current evidence is mixed. For instance, a 2021 study found that after a ride-hailing service such as Uber or Lyft enters an urban market, vehicle ownership increases – particularly in already car-dependent cities – and public transport use declines in high-income areas.

Cities need to re-imagine themselves

Reducing car dependency is not just a nice idea. It is essential for the survival of people and places around the world, which the recent IPCC report on climate impacts makes clear hinges on how close to 1.5°C the world can limit global warming. Avoiding irreversible harm and meeting their Paris Agreement obligations requires industrialised nations such as the UK and Sweden to reduce their emissions by 10-12% per year – about 1% every month.

Yet until the pandemic struck, transport emissions in Europe were steadily increasing. Indeed, current policies are predicted to deliver transport emissions in 2040 that are almost unchanged from 50 years earlier.

Local buses in the Swedish city of Lund, home of the Centre for Sustainability Studies. Shutterstock

To meet the planet’s health and climate goals, city governments need to make the necessary transitions for sustainable mobility by, first, avoiding the need for mobility (see Paris’s 15-minute city); second, shifting remaining mobility needs from cars to active and public transport wherever possible; and finally, improving the cars that remain to be zero-emission.

This transition must be fast and fair: city leaders and civil society need to engage citizens to build political legitimacy and momentum for these changes. Without widespread public buy-in to reduce cars, the EU’s commitment to deliver 100 climate-neutral cities in Europe by 2030 looks a remote prospect.

Radically reducing cars will make cities better places to live – and it can be done. A 2020 study demonstrated that we can provide decent living standards for the planet’s projected 10 billion people using 60% less energy than today. But to do so, wealthy countries need to build three times as much public transport infrastructure as they currently possess, and each person should limit their annual travel to between 5,000 kilometres (in dense cities) and 15,000 kilometres (in more remote areas).

The positive impact from reducing cars in cities will be felt by all who live and work in them, in the form of more convivial spaces. As a journalist visiting the newly car-free Belgian city of Ghent put it in 2020:

The air tastes better … People turn their streets into sitting rooms and extra gardens.

Cities need to re-imagine themselves by remaking what is possible to match what is necessary. At the heart of this, guided by better evidence of what works, they must do more to break free from cars.


World’s protected natural areas too small and isolated to benefit wildlife – new study

David Williams– Lecturer in Sustainability and the Environment, University of Leeds

SimonTheSorcerer / shutterstock

The world’s governments will this year negotiate a series of targets in response to the global biodiversity crisis that has already led to a massive loss of the planet’s wildlife. While none of the previous round of targets agreed in 2010 have been met, the one that gained the most publicity, and arguably the one we got closest to achieving was target 11. Its aim was that:

By 2020, at least 17% of terrestrial and inland water areas and 10% of coastal and marine areas … are conserved through effectively and equitably managed, ecologically representative and well-connected systems of protected areas.

These “protected areas” can range from enormous, strictly-protected areas like US national parks, through the heavily-used landscapes of UK national parks, to tiny urban nature reserves. Protected areas can stop or slow many of the forces threatening biodiversity such as habitat loss, hunting and pollution, and have been a mainstay of global conservation for decades.

By August 2020, some 15% of the world’s land had been protected. This was below the target, but there were enough specific commitments in place to drag the world over the line slightly late. In many ways this is an incredible achievement and perhaps the largest and fastest coordinated change in land management ever.

shaggy haired ox with big horns stood on snow
Musk ox: one of a few mammals living in the world’s largest national park in Greenland. Fitawoman / shutterstock

But the devil is in the detail. For protected areas to be effective they need to be in the right place, and big enough to keep populations of wild species alive. Hundreds of tiny reserves separated by inhospitable farmland may help us reach the 17% target, but they won’t stop extinctions. So, how does our current network stack up? Is it enough to stop species going extinct?

Most animals are underprotected

Colleagues and I recently tackled this question in a study now published in the journal PNAS.

We looked at 3,834 species of terrestrial mammals (all those with available data) and estimated how large a population every protected area in the world could theoretically support (technically, we also grouped adjacent protected areas, as animals can move between them). Understanding how many individuals could survive in each area is vital because small populations just don’t last very long: below a certain size they are much more vulnerable to being wiped out by disease, inbreeding, fires, poaching, or even just falling victim to natural fluctuations in numbers.

To do this, we combined global databases on where animal species live and where the world’s protected areas are located, with site and location specific estimates of population density (how many rhinos – or shrews – do you get per square kilometre).

Worryingly, we found that thousands of species do not appear to be adequately protected. Depending on the exact criteria used, we estimated that at least 1,536 species (40% of those we looked at), and maybe as many as 2,156 (56%) had ten or fewer protected populations that were likely to survive in the long run.

Sign for Gunnersbury Triangle nature reserve
Small protected areas, like this one in London, can only support small populations of most mammals. Any species that cannot survive in the urban environment around the reserve could risk extinction. LWT Gunnersbury Triangle, CC BY-SA

These under-protected species were found across all continents, across all species groups we looked at, and included some of the world’s smallest mammals, as well as some of the largest. Perhaps most concerning, 91% of the world’s threatened mammals – many of which are already the focus of conservation efforts – were under-protected, and hundreds of these species appear to have no viable protected populations at all. These species are at serious risk of population declines or extinctions as habitat outside protected areas comes under increasing pressure.

What is more, these numbers represent a best-case scenario. In reality, protected areas are only effective if they are well-managed, and most simply don’t have the resources.

What works?

Our work suggests that what matters is not the total percentage of the world that is protected, but whether protection is in the right places and whether protected areas are large enough, or well enough connected to other areas, to support populations that will survive in the long term. If not, then they are just delaying the inevitable, and species will continue to be lost from them, whether or not targets have been met.

Expanding or relocating the world’s protected areas comes fraught with very real risks to human wellbeing. These areas are based on stopping people from doing things: from chopping down trees, from hunting certain species, from mining, or from farming.

This is what makes them so valuable to biodiversity, but imposes a huge cost on the local population. Many protected areas have a history of colonialism, forced removals, and the impoverishment or disenfranchisement of local and particularly indigenous people. Any future expansion has to be fair to these people.

Expansion is also only going to be possible if we reduce human demand for land. Protected areas are going to be ever more important as growing human consumption puts unprotected land under increasing pressure.

But they are like treating the symptom of a disease, and we also have to treat the root cause. Without rapid shifts towards healthier, plant-rich diets, reductions in food waste, and sustainable yield increases, there simply won’t be enough spare land to protect.

The world’s biodiversity is in serious trouble, and our current system of protected areas appears unlikely to save it. To prevent a wave of extinctions in coming decades, we need to greatly reduce humanity’s global footprint and to couple this with protected areas that are well managed, well located and large enough.


The problem of simplistic thinking about nature

Some people are more connected to nature than others. We know that most people don’t notice nature, but what do they think about nature? A couple of …

The problem of simplistic thinking about nature

Britain’s first wetland ‘super reserve’ offers boost to nature-based solutions to climate change

Christian Dunn– Senior Lecturer in Natural Sciences, Bangor University

Avalon Marshes wetland, in Somerset, England. IanRedding / shutterstock

Wetlands are the superheroes of the natural world. They are crammed with wildlife, protect our coastlines, keep our rivers clean, and store climate-changing amounts of carbon.

Yet through much of history they have been at best ignored and at worst vilified and destroyed. In recent years public campaigns and money have been thrown at tree planting and reforestation, yet hardly a mention was given to restoring the UK’s bogs, swamps and marshes. But a quick scan through famous literature, paintings and even films and TV series will show you how often wetlands feature as the unpleasant, sinister backdrop of dark storylines.

Fortunately, things are now changing. This was highlighted with the recent announcement of a 15,000-acre Somerset Wetlands national nature reserve. This is the UK’s second so-called “super reserve” after Purbeck Heaths in Dorset. These reserves take in a mosaic of different habitats, and by linking them all together as part of an entire landscape management plan, it is hoped the region as a whole will benefit.

In this case, the new super reserve will encompass existing reserves on Somerset’s levels and moors, a region of coastal plains, fens, reedbeds and saltmarshes, which make up the heart of the county.

Somerset Levels (coastal plain) and Moors (inland floodplain). Nilfanion / wiki, CC BY-SA

These areas are estimated to contain around 11 million tonnes of carbon, in the form of peat: semi-decomposed dead plant material. When peatlands dry out – perhaps because they are drained to make farmland or when peat is extracted for compost – the vegetation decomposes a lot faster, releasing carbon into the atmosphere.

Much of Somerset’s peat deposits have been damaged over the centuries, and continue to be so, releasing hundreds of thousands of tonnes of greenhouse gasses every year. Their protection as carbon sequestering powerhouses is essential if the UK is to hit its net zero goals in the coming decades.

The saltmarshes on the edge of the new reserve are also carbon-dense habitats and can protect the coastline during storms and sea level rises. Then there is the wildlife that teems in this area, from otters and kingfishers to eels and marsh fritillaries (one of Britain’s rarest butterflies).

Orange and blue kingfisher bird sits on branch
Somerset birdlife. Nick Edge / shutterstock

Well-preserved history

It’s not just the environmental and natural benefits provided by the wetlands of the new super reserve that make the project so special.

Britain’s history and heritage is tied up in this area and the acidic, waterlogged peatland conditions means it is uniquely preserved for us to discover. For instance the UK’s oldest wooden walkway, the Sweet Track, was built 6,000 years ago to help Neolithic people cross the marshes. Since it was uncovered in the 1970s it has helped archaeologists understand how these people lived.

Hill in background, swampy river in foreground with bird
Glastonbury Tor towers over Somerset’s wetlands. Matt Gibson / shutterstock

It may also only be a touch melodramatic to state that England as we know it would not exist if it hadn’t been for the Somerset levels and moors “fen-fastness” (as described in the Anglo-Saxon Chronicle), offering King Alfred the refuge and battleground his small force needed when fighting the Vikings in the 800s. (Though whether he burnt some cakes in the process is up for historical debate).

Large-scale protection

It’s not just the Somerset region that will see the benefits of the proposed landscape-scale management plans – the entire country will be richer. Of course, some of the area is already under the supervision of conservation organisations and they are doing a great job. But this project goes beyond those individual sites and brings them all together on a larger scale.

Properly managed individual nature reserves, no matter what the size, can be fantastic. But it’s when we join-up these pockets and expand them that we can really start to control waterflows, maximise biodiversity, reduce carbon emissions and enhance our own wellbeing. Indeed, research is showing it’s at this scale that we can have a real impact and harness the potential of “nature-based solutions” which allow natural ecosystems to help address the climate and biodiversity crisis.

When these areas are large enough and dominated by coastal and freshwater wetlands then the benefits are magnified, as it’s not just a landscape-scale being looked at, or even the seascape, but the “wholescape”.

This “wholescape” approach must be the way forward if we are serious about the use of nature-based solutions this century. And nature’s superheroes — our wetlands – need super nature reserves like the one in Somerset to show us just what they can do.


How to make your lawn wildlife friendly all year round – tips from an ecologist

Sandra Standbridge/Shutterstock

Alongside the worrying current fad for plastic grass, a growing number of people are choosing to let their lawns grow wild in order to encourage a more diverse range of plants and insects to live in them.

You may not be convinced of the beauty of a wild and unruly garden, but there is a sweet spot to be found between a rewilded jungle and a sterile green desert which not only looks good but provides a haven for wildlife. This is especially important in the UK, where 97% of semi-natural grassland has been destroyed over the last 80 years.

I’m an ecologist specialised in the study of this kind of habitat, and I want to help you get the most out of it. One simple compromise you can make is to put off when you first get the lawn mower out each year. A campaign by conservation charity Plantlife called #NoMowMay asks people with lawns to hold off the first cut until June, which allows grasses and herbs time to flower and set seed.

But if you want to maintain a wildlife-friendly lawn throughout the year, without letting your garden become completely overgrown, here’s some advice for what else you can do.

To find a happy medium, some mowing may be necessary. This halts the ecological processes which would otherwise transform a grass lawn into a woodland over time. By varying the height at which you mow different areas of your lawn and how often you do it (simulating the effect of different herbivores grazing in the wild), you can create a mix of conditions which benefit a variety of species.

Areas cut short will favour daisies, which flower in profusion and offer a nectar buffet to bees and butterflies. Unkempt areas left uncut for a year suit a wider variety of flowers, tempting a diverse cast of bugs and other creatures into your garden.

A hoverfly inspects a yellow dandelion in tall garden grass.
Flowers in the long grass have attracted a white-footed hoverfly. Nick Upton/Alamy Stock Photo

In experiments on his own garden in Kent, Charles Darwin recorded that refraining from mowing turf for too long resulted in fewer species overall, because:

the more vigorous plants gradually kill the less vigorous … thus out of 20 species growing on a little plot of turf (three feet by four) nine species perished from the other species being allowed to grow up freely.

Another key thing to think about is the level of nutrients the lawn receives. Even if you have never succumbed to the lawn feed products heavily promoted in most garden centres, your lawn will get a sufficient dose of fertiliser from reactive nitrogen carried on the wind.

The purpose of mowing in a natural grassland should be to mimic grazing by animals. And to do that, you have to remove the clippings otherwise the nutrients they carry will soak back into the soil.

Fungi and bacteria decompose dead plant material and return those nutrients to plants in a lawn through networks of mycorrhizal fungi in the soil. Regular mows which dump the cuttings and overload the soil with nutrients drive a stick through the spokes of this cycle by devaluing the currency of the nitrogen and phosphorus fungi deliver. Clumps of cut grass can also smother small seedlings.

At unnaturally high soil nutrient levels (common in lawns mown and topped with the clippings regularly), the vegetation is dominated by a small number of fast-growing, weedy species. As Darwin found, this prevents a rich community of wildflowers from taking shape. Soil with low nutrient levels favours not only more species, but also healthy soil food webs.

At the Rothamsted Park Grass experiment in Hertfordshire, scientists have studied the effects of annual haycutting since 1860, making it the oldest field experiment in the world. When fertiliser was evenly applied to some plots, it reduced the number of plant species from 40 to fewer than five.

A blue rake on a wooden stick collects grass cuttings in a pile.
Grass cuttings inundate soils with more nutrients than a diverse community of plants needs. Ekaterina Pankina/Shutterstock

Autumn fruiting

You also want to consider the time of year. Mow sparingly and leave grass long in summer to create diverse plant and insect communities in the warmest months. A lawn left uncut until late July, as in a traditional hay meadow, will favour the greatest variety of flowers. But cut it short in autumn to foster conditions for mushrooms fruiting as the year winds down.

Soil organisms and their hidden lives are badly neglected in nature conservation. Among the most overlooked are grassland macrofungi, so named because they are large enough to be visible to the naked eye. My favourites are the brightly coloured waxcaps. These film stars of the fungal world are restricted to undisturbed grasslands where soil nutrient concentrations are low.

The British Isles is a global hotspot for these fungi, but they are threatened by habitat loss. 11 species found in the UK were assessed by international experts as vulnerable – the same extinction risk faced by the panda and snow leopard.

Three pink mushrooms with split edges in grass.
Pink ballerina mushrooms in an Aberystwyth garden. This species is considered globally vulnerable by the International Union for the Conservation of Nature (IUCN). Gareth Griffith, Author provided

A study by my research group showed that waxcaps need the turf to be short (8cm tall at most) in the autumn, but that their most prolific fruiting occurred when the grass was left uncut until mid-July. Waxcaps grow slowly and are long-lived, but with late cuts and the removal of clippings to lower soil nutrient levels, it is likely that the first waxcaps will return within a decade.

To sum up, delay mowing until midsummer, keep your lawn free of clippings and leave patches more unkempt for longer to please butterflies and bees. But give it regular trims from August onwards to encourage globally rare mushrooms. You’ll then see that grasslands are diverse and dynamic habitats just waiting to be unleashed.


Actions for visible biodiversity help noticing nature and nature connectedness

Having a strong connection to nature leads people to undertake actions that help conserve the natural world. Recently we wondered whether this …

Actions for visible biodiversity help noticing nature and nature connectedness

How children are helping to make their families more eco-friendly – new research

Author- Shaheen Hosany Lecturer in Marketing, Royal Holloway University of London Contributors- Hongwei He Chair Professor of Marketing, University of Manchester; Sameer Hosany Professor of Marketing, Royal Holloway University of London

Children can influence their families to follow greener lifestyles. Shutterstock

The UN climate change panel IPCC has warned that 2030 is our deadline for halving global carbon emissions to prevent climate catastrophe. Such a stark threat has seen a surge in youth climate activism across the planet. Millions of young people have sprung into action, striking from school and taking to the streets or social media to galvanise action against climate injustice.

It’s clear that supporting children to care for the natural world from a young age is vital if we are to build an eco-friendly future. And a huge part of children’s environmental learning, or “socialisation”, occurs through observation and role modelling. Learning to emulate family, teachers, peers, admired celebrities or public figures – and being exposed to nature – shapes how children grow up to treat the environment.

As experts in marketing and consumption, we’ve been researching how children and young people up to 19, across genders and geographies, develop predispositions towards sustainability through socialisation.

Primarily, it’s parents or caregivers who teach their children to conform to society’s environmental norms and expectations. By transmitting their own values or guiding principles, they pass on their beliefs about what behaviour is “acceptable”. Crucially, the way parents talk about sustainability – whether positive or negative – influences how children grow up to think about it themselves.

The UN climate change panel IPCC has warned that 2030 is our deadline for halving global carbon emissions to prevent climate catastrophe. Such a stark threat has seen a surge in youth climate activism across the planet. Millions of young people have sprung into action, striking from school and taking to the streets or social media to galvanise action against climate injustice.

It’s clear that supporting children to care for the natural world from a young age is vital if we are to build an eco-friendly future. And a huge part of children’s environmental learning, or “socialisation”, occurs through observation and role modelling. Learning to emulate family, teachers, peers, admired celebrities or public figures – and being exposed to nature – shapes how children grow up to treat the environment.

As experts in marketing and consumption, we’ve been researching how children and young people up to 19, across genders and geographies, develop predispositions towards sustainability through socialisation.

Primarily, it’s parents or caregivers who teach their children to conform to society’s environmental norms and expectations. By transmitting their own values or guiding principles, they pass on their beliefs about what behaviour is “acceptable”. Crucially, the way parents talk about sustainability – whether positive or negative – influences how children grow up to think about it themselves.

It’s not just about parents, though. If children see their role models’ genuine concern about or efforts towards cutting food waste, reusing bags, bottles and cups, and taking energy-efficient transport, they’re likely to do the same.

A family walk through a forest
Introducing children to nature can help them engage with climate change. Shutterstock

What’s more, introducing children to natural landscapes such as forests, the wonders of wild and marine life, and the dangers of pollution from an early age helps them appreciate and care for the environment.

Our research also reflects on how children transmit acquired values, beliefs, norms, knowledge and skills back to their families – potentially altering family behaviour – via the process of “reverse socialisation”.

Read more: Does having children make us care more about the environment?

If a child learns from their teacher about the damaging effects of CO₂ emissions, they may ask their families to reduce car use or take eco-friendly holidays in local spots rather than overseas. And putting recycling bins in schools may encourage kids to ask parents whether they can introduce them at home.

Now, brands are beginning to note how children are encouraging their parents to be greener through pushing them to recycle, cycle or scoot short distances, and compost.

Multinational companies including Procter and Gamble and H&M already acknowledge children as key drivers of sustainability by making them the focus of campaigns highlighting their environmental credentials.

A mother and child play with Lego on the floor
Kids can socialise their caregivers to become more eco-conscious. Shutterstock

Prompted by letters from their main customers – childrenThe Lego Group is aiming to make all packaging recyclable by 2025 and exploring ways to build its famous bricks without plastic.

Teaching sustainability

One of the most important places children pick up ideas about the environment is at school. The UK Department for Education’s recent policy paper, on making education more focused on sustainability, is evidence of the government’s growing concerns around how schools can help children become greener citizens.

But these policies can only do so much. We don’t know whether teachers will have enough time to engage with extra environmental teaching, given the demands of the existing curriculum. Also, lessons on sustainability aren’t featured across the curriculum, and kids beyond 14 can opt out from subjects like geography and natural history.

Four children play in nature
Government strategies aim to get kids involved with the natural world. Shutterstock

Alternatively, climate learning can be encouraged on screen through virtual reality – providing the opportunity to experience simulated environmental changes due to extreme weather or visualise oceans filled with plastic – or the use of gardening-focused games such as Gro Garden, Gro Recycling and Eco Warriors. And as proposed by the Department for Education, a virtual National Education Nature Park, allowing kids to upload their progress in learning about biodiversity onto digital maps, can help reinforce connections with nature.

It’s clear that getting children involved in sustainability wherever they live will encourage environmental practices that will feed back to their families, helping to create green traditions that can hopefully last a lifetime.


Neighbourhood green space is in rapid decline, deepening both the climate and mental health crises

Matthew Adams– Principal Lecturer in Psychology, University of Brighton

Tom Falcon Harding / shutterstock

The past 20 or so years of housing development in England and Wales has decimated community access to green space. That’s according to a new report from think tank the New Economics Foundation (NEF), which has brought together data on the age of housing developments, public green space provision and public perceptions of green space in their local area.

As an academic researching and writing the role of access to nature in health and wellbeing I was shocked by the detail of the report.

“Green space” in this sense means any public area in a town or city that includes plant life or water features (sometimes referred to as blue space), set aside for recreation. This can be a whole park or woodland, street trees or simply a small patch of grass.

The new report points to some stark differences in the accessibility and quality of green space provision depending on when most of the houses in the area were built – and, as the report’s authors point out, the planning laws at the time that governed their design.

It turns out that in general, the newer the housing that dominates an area, the less the total amount of green space within a 1km radius. The most recent generation of housing, built between 2009 and 2021, has up to 40% less local green space than areas where the homes are mainly late 19th- and early 20th-century.

Unsurprisingly then, people living in post-2000 developments are significantly less likely to visit green spaces, a loss the NEF calculates as nine million fewer trips each year. They are also less likely to report having access to a private garden, or “feeling part of nature”. Basically, we’re creating a new generation of neighbourhoods with very little green space, adding to a well-documented decline in pre-existing public green space.

Access to nature is an equality issue

Why does this matter? There is now substantial evidence that points to the importance of green space for human health and wellbeing. Psychological studies suggest that if we spend time in nature regularly, we are more likely to report positive mood and cognition, lower anxiety, higher creativity, mindfulness and social connectedness. These benefits are greater if we have a strong sense of our connection to nature and take the time to notice our surroundings.

Person stands on grassy hill and looks over town
Nature is a mood-enhancer. Malgosia Janicka/Shutterstock

It follows that a widespread reduction in everyday nature contact, on the kind of scale reported by the NEF, means the reverse, with the potential to threaten the physical and mental health of thousands, perhaps millions of us.

This is why routine access to nature has become an equality and justice issue, with research highlighting existing inequalities in green space access, and campaign groups calling for local nature access to be established as a legal right.

Surprising? Possibly not. During recent lockdowns, with the usual distractions suddenly out of reach, many of us developed a new or renewed sense of the benefits of time spent in nature.

Good for humans, good for the environment

But there’s another reason, perhaps more surprising, to expose and reverse this decline in access to green space. Psychological research suggests that it also threatens our chances for averting environmental catastrophe, now and in the future.

Generally speaking, the higher the degree of our sense of connection to nature, the stronger our moral concern and care for the environment. This is reflected across a wide range of private and public practices, for example in higher reports of recycling or environmental volunteering. Contact with and connectedness to nature are not quite the same thing, but they tend to be mutually reinforcing – the more time we spend in nature, the more we feel connected to it and vice versa.

A widespread reduction in local green space reduces how often people access nature-rich spaces, which erodes their sense of a connection to nature, and combined these losses affect how much we are committed to care for and protect nature – even how much we notice its decline in the first place.

Potentially we then come full circle – with fewer of us feeling a strong moral environmentalist concern, we become bystanders as the climate and biodiversity crisis deepens, and options for human-nature relationships decline further, apart, perhaps, for the most privileged.

Being charitable to the UK government, we might say this is a case of the right hand not knowing what the left is doing – after all the UK is currently investing over £4 million in pilot “green social prescribing” projects, explicitly promoting the benefits of nature-based health interventions.

However, moves like this are meaningless if we take for granted the access to and quality of nature and natural environments in the first place, while willingly (or otherwise) overseeing its rapid decline. Healthy nature contact requires joined-up public planning and strong investment in infrastructure.

It is time for the government to oblige planners, developers and public bodies to make sure everyone can access and develop a connection with the natural environment. Neighbourhood green and blue space is an essential component of a sustainable transition for the UK, with the potential to help address a crisis in health and wellbeing as well as the wider environment.


Children’s physical activity dropped during COVID lockdowns but didn’t bounce back – new UK research

Ruth Salway– Senior Research Associate in Statistics/Epidemiology, University of Bristol


During the COVID pandemic, lockdowns and school closures brought about significant changes to children’s opportunities to be active. While the precise rules varied around the world, most countries experienced some level of restrictions for a time.

Unsurprisingly, when everything is closed and the guidance is to stay at home where possible, activity levels go down. For children, when schools are closed, there’s no walking or cycling to school, no physical education lessons, no playing in the playground and no clubs after school. Where their access to parks and play areas is restricted, and when sports clubs and facilities are closed, kids lose further opportunities to be active.

So it’s not surprising that evidence from around the world shows children were doing less exercise at the height of the pandemic. But what about when restrictions began to lift, and schools reopened? Our new research suggests physical activity among children in the UK didn’t bounce back to pre-pandemic levels.

What we did

In our study, we measured the physical activity levels of 393 children aged 10-11 and their parents, recruited from 23 primary schools in the Bristol area between May and December 2021. At this time, schools and many other venues had re-opened, and during that summer most legal limits on social contact were removed.

We then compared participants’ activity levels with data from 1,296 children (also aged 10-11) and their parents from the same schools gathered three years earlier. By using information from this earlier research, we were able to see if there were differences in child and parent physical activity when we conducted our study, compared with before the pandemic.

To measure activity at both time points, each child wore an accelerometer, a small device worn at the hip that is like a very accurate pedometer. For each child, we calculated the average time spent doing moderate-to-vigorous physical activity each day.

This is activity that gets children slightly hot, slightly sweaty and out of breath. The UK chief medical officers recommend that all children and young people should do an hour of this type of activity every day.

We also calculated the children’s average sedentary time – time spent sitting down or not moving very much – and collected information about travel to school, after-school clubs and screen viewing from both children and parents via questionnaires.

Read more: Children exercised less during lockdown – here’s how to get them moving again

We found that even though most COVID restrictions had been lifted by the time we collected our data, the children were less active compared to kids of a similar age before the pandemic.

On average, children did around eight minutes less moderate-to-vigorous physical activity per day in 2021, compared with before the pandemic – a drop of 13%.

We also saw a rise in sedentary time of nearly half an hour per day during the week, and of 15 minutes at weekends. However, unlike some studies undertaken during COVID lockdowns, we didn’t see differences by gender or socio-economic background – physical activity fell and sedentary time was higher in all groups by about the same amounts.

We also found no difference in the physical activity of the parents in our study, when compared with our pre-COVID group. So unlike their children, any drop in physical activity parents might have experienced during lockdown reverted to normal levels.

A girl watches a smartphone screen.
COVID lockdowns have seen children doing less physical activity. beto_junior/Shutterstock

Some challenges

It’s tricky doing data collection and research during a pandemic. Some of our data collection was done remotely and some in person, while COVID outbreaks in schools meant we sometimes had to reschedule data collections at short notice. And it’s always possible that something other than the COVID pandemic is responsible for the trends we observed – although it’s difficult to imagine what, especially given the evidence from other studies and countries.

It’s important now to see if this pattern continues or changes over time. If the lower levels of physical activity do persist, we need to understand what’s causing this – and what we can do to encourage children to be more active again. We plan to explore these issues further in the next phase of our study, but we also need wider research in other parts of the UK, and other countries, to fully understand the scale of the problem.

Read more: Rewild your kids: why playing outside should be a post-pandemic priority

Physical activity is very important for children’s health and wellbeing. It’s a concern if what we perceived would be short-term reductions in activity during the pandemic may, in fact, be longer-lasting. Families, schools and communities need to work together to make sure the opportunities are there for all children to be physically active as we emerge from the COVID pandemic.


How filling the UK’s unused land with fruit and veg could help make us and our environment healthier – and help fight inequality

Jess Davies– Chair Professor in Sustainability, Lancaster University Charlotte Hardman– Senior Lecturer in Psychology of Appetite and Obesity, University of Liverpool Sofia Kourmpetli– Lecturer in Plant Sciences, Cranfield University

Campaigners are calling for the right to grow fruit and veg in the UK’s unused public spaces.

Communities should have a right to improve the unloved public spaces around them by growing fruit and vegetables, according to a new campaign that’s calling for a “right to grow” law in the UK.

This law, akin to the Countryside & Rights of Way Act that first gave the public the right to roam across parts of Britain’s countryside in 2000, aims to get local councils and landowners – such as the NHS and water companies – to open up parts of land in towns and cities for cultivation by local citizens.

Initiatives like Incredible Edible, who are leading the campaign, have been successfully taking over public spaces with food growing projects for over a decade now. We set out to understand how opening up these spaces to anyone who wants to grow food could contribute to improving environmental, physical and mental health across the country.

The security of our national food supplies in the UK is a question of growing importance. The pandemic and Brexit have given us a taste of what food shortages can be like: and with the invasion of Ukraine, and the cost of fuel and fertilisers rising, more turbulent times seem inevitable. Since 84% of fruit and 46% of vegetables eaten in the UK are imported, these vital food groups are particularly vulnerable to supply crises.

Plants in a planter, with a sign reading 'The revolution will be fertilised!'
Incredible Edible launched in 2007. Dunk/Flickr, CC BY-SA

Our research suggests that if all the green space across England, Scotland and Wales was used to grow food, it could provide around 40% of the fruit and veg currently produced in and imported into the UK. Publicly owned land makes up just under half of total green space, so even if just a small fraction of public spaces was used, it could make a huge difference to the availability of healthy food.

While this kind of urban agriculture is unlikely to ever replace conventional farming, it could play a big role in boosting food supply resilience and perhaps help ease some of the UK’s growing food insecurity.

Harvesting health

People get more than just fresh fruit and vegetables when going outside to grow: there’s now heaps of evidence for the health and wellbeing benefits of spending time in nature. Our research suggests that engaging in food growing might not only bring some of these benefits, but also lead to making healthier and more sustainable food choices.

A person smiles against a background of vertical plants
Urban growing can change how cities are structured. RawPixel

Urban growers in our surveys were more likely to have a higher quality diet when compared to non-growers. Our work suggested that this might be because growers care more about the food they eat, where it comes from and where it was grown.

Enhancing ecosystems

Nowadays, our food tends to come with an environmental cost. The agriculture and food sector plays a huge role in climate change, accounting for around a third of greenhouse gas emissions. Agriculture also has many other detrimental environmental effects, including being the primary contributor to biodiversity loss and a major driver of water quality problems.

The jury is still out when it comes to whether urban growing has a lighter environmental footprint than conventional growing, with a recent study suggesting we need better data to decide. But as well as producing healthier, more local food, urban growing also changes the environment of the city itself.

Our recent review of the evidence to date suggests that urban food growing spaces like farms and allotments can deliver as diverse a range of ecosystem benefits as other urban green spaces such as parks and school grounds. They can help clean the air, regulate local climates, store more carbon, cut the risk of flooding and encourage biodiversity to flourish.

A person stands outside a farm food shop
Food grown in cities, like here at Spitalfields City Farm, can help support community initiatives. Lucy Miller/East London Advertiser

Growing food in towns and cities could be a great way to make the most of our land, and at the same time address the pressing challenges we face when it comes to food, health, social and environmental inequalities. As acknowledged by the appointment of the House of Lords Land Use in England Committee earlier this year, deciding how to best use our land is a growing national priority.

We need land that supports better diets and helps lift people out of food poverty. We need land that fights climate change by reinforcing carbon sequestration and encouraging biodiversity, while still providing affordable homes and thriving places to live and work.

All this means we cannot afford to overlook those little fragments of land in towns and cities that are currently lying forgotten and unused. A “right to grow” law could be one way to bring these to life, while empowering people who love where they live to help improve it.