The international Ecocity Standards call for “Healthy Biodiversity” (www.ecocitystandards.org). This means that the range of plants and animals living in local, bioregional and global ecosystems is sustained, and that natural habitat is restored. Conservation of habitat has been an important strategy to ensure nature’s long-term viability. However, in today’s increasingly urban world, this tried and true approach is proving inadequate. According to the World Wide Fund for Nature, representative populations of thousands of vertebrate species have declined by 52% since 1970 (WWF 2014). Simultaneously, the global human population has doubled with half of humanity now living in cities (UNDP 2009). Although cities can provide resource efficient lifestyles, they are also nodes of consumption. They draw in vast amounts of resources for food, energy and water and extrude equally vast amounts of wastes that ultimately must be absorbed by local and global ecosystems. The three primary causes of species population decline are: i) exploitation of a species through hunting and fishing by humans for food or sport, ii) habitat change or degradation caused, for example, by climate change that affects the ability of certain species to hunt or forage successfully, and iii) habitat loss due to changes in land use (e.g., converting forests to fields for agriculture) or complete degradation such that terrestrial or aquatic ecosystems can no longer support the species in question (WWF 2014). Connections between wild spaces and urban places can be made through ecological footprint analysis. Ecological footprint analysis estimates the amount of land needed to both yield the resources consumed in cities and to sequester the wastes produced by cities. We can compare the total land area used in service of human consumption to what is needed to sustain plants and animals in their natural habitats. Understanding the resources required to support wild spaces and urban places can inform what the World Wide Fund for Nature calls a “one-planet perspective” that is capable of integrating the often competing demands of an urbanizing world and those of the natural world upon which all life depends. Ecocities, cities that are built in balance with nature, represent a very important part of the solution.
WWF (World Wide Fund for Nature), 2014. Living Planet Report. World Wide Fund for Nature, Gland Switzerland. http://wwf.panda.org/about_our_earth/all_publications/living_planet_report/
UNPD (United Nations Department of Economics and Social Affairs, Population Division), 2009. World Urbanization Prospects: the 2009 Revision: File 2: Percentage of Population Residing in Urban Areas by Major Area, Region and Country, 1950e2050. http://esa.un.org/unpd/wup/index.htm.