What makes a city resilient? This is an important question for the urban planners and policymakers who are designing the cities of the future. They are cities that must serve the needs of an ever-growing population while remaining cohesive, be able to recover from shocks and disturbances and, importantly, be vibrant and pleasant places to live. Resilience as a concept is as old as time itself. It is a naturally occurring quality in natural and human systems, including urban systems. So it stands to reason that to understand more about what makes a city resilient, we must learn from the settlement’s that have survived upheaval.
This is the idea behind the work of researchers from the Stockholm Resilience Centre, Stephan Barthel and Sverker Sörlin, who have studied the ancient civilisation of Constantinople in a new book on urbanism and environmental dynamics. Today, of course, Constantinople is known as Istanbul, one of the top 20 most populous cities on earth, home to more than 13 million people. It is a city that is still inhabited, still functioning and still relevant after 3000 years of history. It has survived a plague, war and economic regression and stands today as one of the most geographically important cities on earth linking, as it does, the two great continents of Europe and Asia. But what was it that made Constantinople and later, Istanbul, so successful in developing despite regular disturbances and shocks? And what lessons do ancient civilisations hold for today’s modern metropolises?
Barthel and Sörlin’s central message for modern cities is this; keep plenty of green, open spaces for food production and social interaction. One of the principal factors that have contributed to Constantinople’s resilience is its ability to produce large quantities of food from within the city itself, reducing the people’s reliance on imported supplies.
This self-sufficiency was crucial to the city’s survival in times of stress. When the city was under siege its citizens benefited from their rulers’ foresight in investing not only in military infrastructure, but in large food stores, and food production systems. Barthel and Sörlin explain that even “when sieges were efficient and supplies ran dry, there were still possibilities to cultivate food within the city walls and catch fish in the Golden Horn. Hence Constantinople had a variety of options to sustain the city with food.”
It is true that it is hard (but not impossible) to imagine cities such as London or Manchester under siege by an invading army, but it is easier to envisage the chaos that might ensue if the supermarket shelves were left bare thanks to supply-chain failure, or after a failure to adapt our food systems to a world without limitless supplies of oil. Last year’s riots certainly gave a glimpse of how close social unrest is to bubbling over the surface.
And it is this social cohesion that Barthel and Sörlin’s research points to as a second, essential component of resilient urban areas. In particular, their work suggests that Constantinople was able to survive shock thanks to its stocks of ‘social memory’. ‘Social memory’ is a product of a cohesive society that has experienced difficulties in the past. A social structure that is able to learn from past crises and crucially, share this knowledge within the community. It is not enough for a city to have simply experienced shocks in the past if it does not have the capacity to learn from these mistakes. Barthel emphasises this point saying that “another aspect of sustaining resilience is the ability to store, and possibly transform, insights over time and use them under new circumstances”.
So how do city planners and policymakers ensure that metropolitan areas are able to retain stocks of social memory? Research suggests that one way of doing so is through establishing and retaining green spaces with allotment gardens being particularly beneficial. In a study that makes the Communities Secretary, Eric Pickles’ plan to allow councils to sell off the UK’s 300,000 allotments look spectacularly short sited, allotments were found to be crucial to maintain resilience.
The study, which is to be published in an upcoming edition of the journal Global Environmental Change, shows how allotments have been a source of resilience during periods of crisis. Researchers conducted surveys and interviews with hundreds of gardeners in Stockholm over a four-year period. They found that these green spaces supported many valuable ecosystem services that were beneficial far beyond the garden fence. They also saw how they served to increase the skills of the local community and reduce “ecological illiteracy”.
Less than 100 years ago, during the First World War, the British were told to ‘Dig for Victory’. The number of allotment’s surged to reach over 1.5 million. Famously, even Buckingham Palace turned over its lawns to grow vegetables, a move that has been echoed by today’s occupants of the White House. The latest research suggests that, in order to maintain resilient cities, policy-makers should actively encourage citizens to maintain or engage with urban green spaces.
The urban population is expected to increase substantially over the coming decades, and as such, our cities are crucial arenas for sustaining sustainable communities, businesses and economies. Perhaps the first and most important step in ensuring we create the resilient cities that are needed is to acknowledge and accept cities, not as an ecological problem, a necessary evil, but to see them as having the potential to support healthy ecosystems and foster resilience.
Watch a video of Ann Kinzing, associate professor of Arizona State University, on the challenges and opportunities in turning urban systems more sustainable:
Barthel S., et al., (2011) Innovative Memory and Resilient Cities: Echoes from Ancient Constantinople. In Paul Sinclair, Frands Herschend, Christian Isendahl and Gullög Nordquist. (Eds). The Urban Mind, cultural and environmental dynamics, Studies in Global Archaeology 15. Sweden, Uppsala University Press.
Barthel S, Folke C, and Colding J. (In press) Social-ecological memory in urban gardens — Retaining the capacity for management of ecosystem services. Global Environmental Change.
Will Bugler is Editor at Get Resilient, he has worked within the ‘Adapting to Climate Change’ department at Defra, Friends of the Earth, and for the UK government’s advisory body on climate change issues; The Energy and Climate Change Committee.