"The urban ecosystem": How should we design cities to make the most of green space?

Lungs of New York: Central Park in 2010. Image: Gryffindor/Wikimedia Commons.

Back in 1839, public health expert J F Murray published his article The Lungs of London, in Blackwood’s Edinburgh Magazine. Even then, city dwellers appreciated the advantages of open, green spaces. Murray described the benefits of the parks of London as “great vehicles of exercise, fresh air, health, and life to the myriads that congregate in the great metropolis”.

Living in cities offers numerous advantages in terms of employment, education, healthcare and social communication, among others. But urban living also comes with its challenges: in particular, urban environments can put a strain on mental and physical health, because they tend to be noisy, polluted, overcrowded and hot.

Ecologists are increasingly turning their attention to urban areas, in an effort to find solutions to these problems. Their work is beginning to show us how cities can be designed to accommodate all the advantages – and minimise the disadvantages – of urban living.


Specifically, urban ecologists are considering how we can enhance “ecosystem services” for those living and working in cities. It is now widely recognised that ecosystems – including urban ecosystems such as parks, protected areas and waterways – provide essential services for people. Temperature regulation, air purification, noise reduction, human well-being, carbon storage (both above and below ground), water infiltration, agricultural production, pollination, and pest control – all of these are examples of the services that urban ecosystems can provide.

Of course, besides services there are also so-called disservices, such as noise pollution and high temperatures, that can be associated with open spaces. For instance, some people find that the dawn chorus of birds in spring affects their sleep patterns; or that they suffer from hayfever when there are high pollen counts.

But now, armed with an understanding of ecosystems and the services they provide, ecologists are able to shine some light on a central question in urban planning: should cities be designed so that intensive and extremely compact urbanisation sits alongside separate, large, continuous green spaces – an approach known as “land-sparing”? Or, is it better to adopt “land-sharing”, where compact green spaces are scattered throughout the urban sprawl?

Sharing or sparing?

A recent study by researchers from the University of Exeter and Hokkaido University, Japan, found that land-sparing is the most effective approach to maintain the majority of ecosystem services. But they also recognise that some degree of land-sharing is important, especially when it comes to the ecosystem services that benefit our well-being.

 

A bit of both. Image: Lawrence OP/Flickr, CC BY-NC-ND.

Being near high-quality green space can provide important health benefits, as well as “cultural ecosystem services”, such as places for recreation, spiritual and religious enrichment, education, cultural heritage, inspiration, social gatherings, and cultural diversity. If a city is to provide these services, it needs to be designed so that people can quickly and easily access green spaces as part of their everyday activities.

The authors of the study concluded that the best way to ensure the optimum distribution of development and green space is to take a top-down, policy-led approach. Changing the design of a city is no easy matter, but we know from experience that it can be done.

As far back as 1809, architect John Nash began work on Regent’s Park in London, where much of his input can still be seen today. In 1858, Frederick Olmsted won the competition to design Central Park in the heart of New York. And in the 1870s, Baron Haussmann – who was charged with redesigning Paris – wanted to join the Bois de Boulonge with the Bois de Vincennes to make a green belt around the city.

These are all perfect examples of land-sparing – but it is worth noting that these green spaces were established when the cities were already in the process of being redesigned.

Berlin's Tempelhof Park in May 2010. Image: Times/Wikimedia Commons, CC BY-NC-SA.

A more recent example of land-sparing is the 300 hectare Tempelhof Airport in Berlin. The site was earmarked for development, but the public voted to retain it as a large, open, green space in May 2014. Ingo Gräning, of the state-run Tempelhof Project stated: “No other city would treat itself to such a crown jewel [of open space]”.

Of course, not all cities have enough available land to “treat” themselves in this way. In densely-built cities like Hong Kong, the opportunity to create large open spaces may never arise. Berlin is an exception – many cities do not have the option of dropping a large park into a built-up area, and in most cases it is not feasible to combine lots of small parks and gardens into a large green area. A lot depends on the history of a city and its geography, and land-sparing is not an option for every location.


Ebenezer Howard – the first modern urban planner theorist – recognised this, when he initiated the Garden City movement in 1898. His aim was to bring the advantages of nature to city dwellers, by introducing compact green areas and small parks into cities. The first examples of Howard’s organised land-sharing can still be seen today, in the UK towns of Letchworth and Welwyn.

So when asking ourselves which approach is best, there is no straightforward answer. Whether land-sparing or land-sharing is most effective will depend on the context; factors such as the shape of the land and the existing developments in the area will all play a part.

But there is no doubt that cities benefit from the services offered by urban ecosystems, and both land-sparing and land-sharing are important means of providing these advantages.The Conversation

Philip James is professor of ecology, University of Salford

This article was originally published on The Conversation. Read the original article.

 
 
 
 

CityMetric is now City Monitor! Come see us at our new home

City Monitor is now live in beta at citymonitor.ai.

CityMetric is now City Monitor, a name that reflects both a ramping up of our ambitions as well as our membership in a network of like-minded publications from New Statesman Media Group. Our new site is now live in beta, so please visit us there going forward. Here’s what CityMetric readers should know about this exciting transition.  

Regular CityMetric readers may have already noticed a few changes around here since the spring. CityMetric’s beloved founding editor, Jonn Elledge, has moved on to some new adventures, and a new team has formed to take the site into the future. It’s led by yours truly – I’m Sommer Mathis, the editor-in-chief of City Monitor. Hello!

My background includes having served as the founding editor of CityLab, editor-in-chief of Atlas Obscura, and editor-in-chief of DCist, a local news publication in the District of Columbia. I’ve been reporting on and writing about cities in one way or another for the past 15 years. To me, there is no more important story in the world right now than how cities are changing and adapting to an increasingly challenging global landscape. The majority of the world’s population lives in cities, and if we’re ever going to be able to tackle the most pressing issues currently facing our planet – the climate emergency, rising inequality, the Covid-19 pandemic ­­­– cities are going to have to lead the way.

That’s why City Monitor is now a global publication dedicated to the future of cities everywhere – not just in the UK (nor for that matter just in the US, where I live). Our mission is to help our readers, many of whom are in leadership positions around the globe, navigate how cities are changing and discover what’s next in the world of urban policy. We’ll do that through original reporting, expert opinion and most crucially, a data-driven approach that emphasises evidence and rigorous analysis. We want to arm local decision-makers and those they work in concert with – whether that’s elected officials, bureaucratic leaders, policy advocates, neighbourhood activists, academics and researchers, entrepreneurs, or plain-old engaged citizens – with real insights and potential answers to tough problems. Subjects we cover include transportation, infrastructure, housing, urban design, public safety, the environment, the economy, and much more.

The City Monitor team is made up of some of the most experienced urban policy journalists in the world. Our managing editor is Adam Sneed, also a CityLab alum where he served as a senior associate editor. Before that he was a technology reporter at Politico. Allison Arieff is City Monitor’s senior editor. She was previously editorial director of the urban planning and policy think tank SPUR, as well as a contributing columnist for The New York Times. Staff writer Jake Blumgart most recently covered development, housing and politics for WHYY, the local public radio station in Philadelphia. And our data reporter is Alexandra Kanik, whose previous roles include data reporting for Louisville Public Media in Kentucky and PublicSource in Pittsburgh, Pennsylvania.

Our team will continue to grow in the coming weeks, and we’ll also be collaborating closely with our editorial colleagues across New Statesman Media Group. In fact, we’re launching a whole network of new publications, covering topics such as the clean energy transition, foreign direct investment, technology, banks and more. Many of these sectors will frequently overlap with our cities coverage, and a key part of our plan is make the most of the expertise that all of these newsrooms combined will bring to bear on our journalism.

Please visit citymonitor.ai going forward, where you can also sign up for our free email newsletter.


As for CityMetric, some of its archives have already been moved over to the new website, and the rest will follow not long after. If you’re looking for a favourite piece from CityMetric’s past, for a time you’ll still be able to find it here, but before long the whole archive will move over to City Monitor.

On behalf of the City Monitor team, I’m thrilled to invite you to come along for the ride at our new digs. You can follow City Monitor on LinkedIn and on Twitter. If you’re interested in learning more about the potential for a commercial partnership with City Monitor, please get in touch with our director of partnerships, Joe Maughan.

I want to thank and congratulate Jonn Elledge on a brilliant run. Everything we do from here on out will be building on the legacy of his work, and the community that he built here at CityMetric. Cheers, Jonn!

To our readers, on behalf of the City Monitor team, thank you from all of us for being such loyal CityMetric fans. We couldn’t have done any of this without you.

Sommer Mathis is editor-in-chief of City Monitor.