Sunday, February 13, 2011
Were ancient cities sustainable ?
As an archaeologist, I have a very different view of sustainability than most scholars who study the contemporary world. For sustainability today, one of the standard definitions is that of Gro Harlem Bruntland: “Sustainable development is development that meets the needs of the present without compromising the ability of future generations to meet their own needs.” There is much debate and discussion about this definition and its usefulness, but the dual components of current practices and potential future outcomes are fundamental for most writers.
Archaeology deals with human society over long time spans—centuries and even millennia. For me, a sustainable society is one that lasts for a long time. In central Mexico, Teotihuacan society flourished for five centuries or more, while many of the societies that came later were only around for a couple of centuries before collapsing. Teotihuacan was far more sustainable. People sometimes wonder why Classic Maya civilization collapsed, assuming that their society and practices must have been defective. But the Maya cities lasted even longer than Teotihuacan. My own society in the USA has lasted less than half as long as the Classic Maya, so perhaps the Maya had a more sustainable society than we have today.
As for urban sustainability, consider these three definitions:
• “a sustainable city is one in which the community has agreed on a set of sustainability principles and has further agreed to pursue their development” (Munier 2007:17).
• “For cities, I have defined sustainability as reducing Ecological Footprint (energy, water, land materials, waste) while simultaneously improving quality of life (health, housing, employment, community) within the capacity constraints of the city” (Newman 2006).
• “when we talk about urban sustainability, we should consider several issues: survival of the settlement through time, environmental impacts on landscapes, and quality of life for inhabitants” (Grant 2004:24).
The first definition cannot be applied to ancient cities. Even if people in ancient Babylon, say, had agreed on sustainability principles (a laughable idea), we would not have any evidence of this today. The second definition at least makes sense to an archaeologist. But only the third definition (by Jill Grant) is really applicable to ancient cities.
The study of modern urban sustainability does not ask whether cities will fail or not, but whether a given quality of urban life can continue into the future. One reason for this neglect of what seems an obvious question to an archaeologist is the fact that, in the words of Thomas Campanella (2006:142), “the modern city is virtually indestructible.” Research on the effects of natural disasters on contemporary and recent cities shows that modern cities (from Beirut to New Orleans) nearly always survive just about anything that nature or people can throw at them.
The reasons for the resiliency of modern cities in the face of physical disaster are listed by Campanella (2006:142):
1. modern nation states have a vested interest in the well-being of their cities.
2. private property laws ensure the continuing organization of urban space, even after physical destruction.
3. the modern insurance industry lessens economic impacts of disasters.
4. urban infrastructure is complex and multilayered, and is rarely destroyed totally.
These conditions do not hold for most preindustrial cities, making it difficult to compare ancient urban sustainability (how long did cities survive?) with modern sustainability (can present lifestyles continue into the future?). Campanella (2006:141) goes on to suggest that the situation was only slightly different in the past. He asserts that after A.D. 1100 very few cities were destroyed or abandoned. Now any archaeologist who has undertaken a landscape survey knows this is not the case; landscapes all over the world are littered with destroyed and abandoned urban sites. Many ancient cities failed, but should we consider them sustainable or not? This is a topic that needs much more research by archaeologists. The current infatuation with societal collapse (e.g., Diamond 2004) takes our perspective away from sustainability and gives a biased picture of ancient societies. Instead of claiming that the Classic Maya were deficient because their cities collapsed, perhaps we should call them wildly successful for forging a vibrant civilization in a harsh environment that lasted for many hundreds of years.
I find it remarkable that even in the absence of the kind of modern urban safety net described by Campanella, many ancient cities managed to survive for many centuries, and some lasted for millennia (think of Rome or Babylon or Jerusalem). This sure sounds like sustainability to me.
This post is based on some of the themes in Smith (2010).
Campanella, Thomas J.
2006 Urban Resilience and the Recovery of New Orleans. Journal of the American Planning Association 72:141-146.
2004 Collapse: How Societies Choose to Fail or Succeed. Viking, New York.
2004 Sustainable Urbanism in Historical Perspective. In Towards Sustainable Cities: East Asian, North American and European Perspectives on Managing Urban Regions, edited by André Sorensen, Peter J. Marcutullio, and Jill Grant, pp. 24-37. Ashgate, Burlington, VT.
2007 Introduction. In Handbook on Urban Sustainability, edited by Nolberto Munier, pp. 17-88. Springer, Dordrecht.
2006 The Environmental Impact of Cities. Environment and Urbanization 18:275-295.
Smith, Michael E.
2010 Sprawl, Squatters, and Sustainable Cities: Can Archaeological Data Shed Light on Modern Urban Issues? Cambridge Archaeological Journal 20:229-253.
Smith, M. (2010). Sprawl, Squatters and Sustainable Cities: Can Archaeological Data Shed Light on Modern Urban Issues? Cambridge Archaeological Journal, 20 (02), 229-253 DOI: 10.1017/S0959774310000259