A recent exchange with a colleague about the health of Lake Erie ended in something of a stalemate. We both shared concerns about water quality and environmental degradation and how the lake, our drinking water supply, will be affected by harmful algae blooms, climate change-induced weather, and the creation of artificial reefs off the coast of Cleveland from the soil that runs off farms and suburban development upriver.
Where we parted ways was whether a deep ecology or urban ecology approach to change will prevail. Deep ecology would likely put a halt to practices that slowly are degrading the environment. Urban ecology is an approach that starts from the premise that human-influenced landscapes are where we dwell, but innovation and sustainability will deliver benefits both economic and to a thriving ecological system.
In their 2012 book, Applied Urban Ecology , Matthias Richter and Ulrike Weiland explain the origins of urban ecology in Europe and America. Ecologist Howard Odum in 1953 proposed the study of urban-rural gradients. His focus was not on organismal systems but on substances and material flows like energy. His theories led to urban metabolism studies of Brussels in 1974 and Hong Kong in 1981 where the sum total fluxes of energy, water, food and building material were measured.
Cities share the same fundamental condition—they don’t operate sustainably like natural systems where organisms reuse another’s waste.
“Since recycling processes barely exist,” Richter and Weiland write, “warmth, waste water, garbage and waste air are deposited, pass through the urban environment and are the cause of environmental problems.”
In the 1990s, a group of enterprising scientists decided on a path for long-term ecological research that recognized how “urban systems are flow through systems.” The National Science Foundation has funded now-decades Long-Term Ecological Research in two urban sites, Baltimore and Phoenix, to analyze socio-ecological drivers of land management and ecosystem responses. Nitrogen fluxes, social vulnerability, environmental inequity have been researched. Significant theories have emerged in urban ecology—foremost that cities are sources of pollution but also innovation.
In Europe, the “City of Short Distances” emerged as the dominant sustainability paradigm. In America, “New Urbanity” emerged as an alternative to the decline of heavy industry, river and ports, suburbs and reconstruction.
Which brings us back to the conversation about Lake Erie and its future. Let’s apply the Urban Ecology definition of city as ecosystem, which “emphasizes not only the diversity and interactions of the elements of the city, but also the spatial pattern and ecological consequences on a number of scales.”
The first scale to consider is time. Over a short period of time the Cuyahoga River watershed was changed from biodiverse landscape to extremely damaged to its current “novel” state where industry, recreation, residential and environmental elements are vying for the same space. The other scale to consider is the size of the site where a hybrid socio-ecological balance can co-exist.
If there is unanimity that the ecological footprint of a city is the key indicator of its sustainability, how we measure Cleveland’s sustainability is in the land area necessary for sustaining the current levels of resource consumption and waste discharge by our population. Cleveland is certainly not the only city to require possibly hundreds of times the land than our actual physical size to sustain. (We don’t know Cleveland’s metabolism, but, as an aside, required reading for all incoming U.S. presidents is the history of the Roman Empire, which collapsed when it outgrew its land capacity to sustain).
By this definition, the dredging of the Cuyahoga River fails if it doesn’t recognize the geographic and time scale of the problem. The spatial pattern—regional land-use taking up more land to sustain a lifestyle that is on balance resource consumptive upstream needs a true accounting of the ecological consequences throughout the system when deciding the future of the river, the lake and the resources it requires to move soil upstream through the river, only to dredge it, and deposit it as a confined disposal facility on the lakefront. Albeit, urban ecologists would argue that, designed for fish and bird habitat, the future CDFs and artificial reefs in Cleveland could have socio-ecological benefit. But, on balance we’re not supporting a city as an ecosystem with unsustainable levels of land, energy, water and waste moving through and out.