عنوان مقاله [English]
Resiliency is an emerging concept in urban design which fosters new thinking about designing less vulnerable and more flexible cities. From Chicago and San Francisco which recovered from big fires in the nineteenth century, Berlin and Beirut which survived wars in the twentieth century, and New Orleans which - in the face of its geologic and hydrologic limitations - is re-emerging from the Hurricane Katrina in the twenty-first century, to vibrant pockets of everyday urbanism observed in Istanbul, Mumbai and New York, resilient cities manifest the saga of survival, governance, sustainability, adaptability and flexibility. Rooted in ecology, resiliency incorporates environmental considerations into urban design. Both disciplines find resiliency a potent metaphor for understanding ecosystems and cities. Metaphors such as resiliency, tree, or organism stress the nature of the city as a “living thing”. Ecologists typically study both what causes organisms to survive extreme environmental conditions, and what causes them to fail or perish. Just as ecologists think about the persistence of resilient organisms and ecosystems against environmental threats, urban designers think about the benefits of resilient cities captured by new models including “the Photosynthetic City,” “the Renewable Energy City,” “the Eco-efficient City,” “the Carbon Neutral City,” and “the Place-Based City”. In these models resiliency ranges from increasing efficiency by producing energy from waste, wind, and sun; decreasing reliance on oil, consumption of nonrenewable resources, and carbon emissions; decentralizing water and power grids; and water recycling to localizing economic development initiatives and promoting green jobs. The degree to which urban designers can draw inspirations from ecology depends on the two key elements cities and organisms have in common: recovery from “disaster” or “illness” and “absorbing change”. Recovery from disaster or illness in a city or an organism conjures up two options: reverting back to a previous status or pursuing a preferred option. The former represents an “equilibrium” model associated with capacity building and reaching normalcy. Exposure to natural and human-made disasters has prompted the need to reduce vulnerability by increasing safety and adaptability in the city. Post-disaster recovery reconstruction efforts tend to mitigate risk and reduce vulnerability through capacity building. In a “non-equilibrium” model, however, the goal is to promote “flexibility” rather than reduce “vulnerability.” Accordingly, in the spring of 2008, a group of University of Cincinnati planning students explored resiliency in downtown Cincinnati. This research discerns three areas in downtown Cincinnati for adapting to new conditions. These areas grow, thrive, and develop over time based on their internal logic. Resiliency here transcends its typical post-disaster recovery normalcy observed in an equilibrium model, and represents forms that can adapt to short-range, midrange, or long-range change within a nonequilibrium model. Infrastructure includes the areas subject to long-range change, whereas areas subject to mid-range change include public spaces, while areas subject to short-term change consist of temporary urban spaces. These three areas embody the physical and social aspects of flexibility described above.