Rapidly growing cities are a cause and a consequence of enormous socioeconomic and environmental change. As of 2008, over ½ the world’s human population of 7.3 billion people lived in cities, and all population growth in the next 35 years is expected to occur in urban areas. Cities draw from, contribute to, and impact their surrounding landscapes. As cities have grown, their relationships to local and regional landscapes have changed as well. Understanding and managing these interconnections is a key to solving many critical sustainability issues of the 21st century such as supplying adequate food, water and energy while preserving vulnerable populations and ecosystems in the face of population growth and climate change. The Pacific Rim, a fast-growing region with many pressing challenges, has the potential to serve as a leader in formulating solutions through its intellectual assets, innovative capacity, and cultural diversity. The goal of the APRU Sustainable Cities and Landscapes research hub is to advance the sustainability of human societies through analysis and critique that lead to actionable plans for enhancing mutually supportive relationships between cities and their surrounding landscapes.
Our investigations are driven by three core questions: What are the forces that shape the relationships between cities and their surrounding landscapes? In what ways do those relationships affect the long-term sustainability of cities, cultures and Earth ecosystems? How can people manage those relationships to enhance landscape-level sustainability, resilience and adaptive capacity in the face of continued expansion of cities due to demographic shifts and population growth, and the stressors of global change, particularly climate change?
We focus our investigations on four sets of processes: those internal to cities, those occurring within surrounding landscapes, those occurring across urban-rural boundaries, and finally, telecoupling – the transfer of goods and services that connect cities to distant landscapes and economies (Figure 1A). Our primary focus is the spatial geography of processes that connect cities and their local-to-regional landscapes socially, ecologically and economically, creating landscape complexes with substantial cross-scalar interactions and feedbacks that influence, and are influenced by, the topologies of sociocultural and biophysical networks (Figure 1B).
Figure 1. Sustainable Cities and Landscapes Conceptual Model. (A) The interactions between cities and their landscapes are characterized by cross-scalar, functional and spatially situated relationships among processes. (B) These processes include interactions among different issues, for example food, water and energy, each with their own topologies of social, ecological and economic networks.
We posit that dichotomous conceptualizations of “city” and “landscape” must be applied carefully to avoid artificial and inhibitory divisions of what in fact are continuums of landscape processes. We argue that management of the nexus between cities and their surrounding landscapes is central to many of the most pressing sustainability issues faced by societies, including the degree to which cities rely on resources transported from far away, the impacts of cities on regional ecosystems, and the degree to which connections to local and regional landscapes provide health, vitality and a sense of place to urban residents.
Food, water and energy exemplify the cross-scalar and interconnected social, ecological and economic dimensions of sustainability. Traditionally, most food was produced locally or regionally and transported relatively short distances. For many cities and their residents that picture has reversed with the rise of agribusiness and global food distribution. This “telecoupling” of food is a two-edged sword. It has increased certain economic efficiencies by matching the large-scale production of individual crops with the climates and soils to which they are best suited, bringing both staples and luxury items to consumers for less cost, and increasing year-round availability of fresh fruits and vegetables. It has also come at the cost of long-distance transport and associated carbon emissions. It has led to questions about the health of the food produced and the ecological and environmental impacts of agribusiness, spawning a growing organic agriculture movement as well as campaigns to support local agriculture, including food production within cities themselves. The reasons go beyond consuming healthy food and supporting local economies to encompass nuanced motivations such as restoring a sense of place, the sociality of downtown farmers’ markets, and increasing the resiliency of urban food systems as part of disaster preparedness.
The locations and ways in which the food that feeds a city is produced have deep hydrological implications. Producing crops for local, regional and global markets accounts for the vast majority of all fresh water used by people. Simultaneously, people in cities need fresh water for drinking, washing, sewage systems and industry. Water is essential for native ecosystems and their associated biodiversity, especially through dynamic river flow regimes and associated sediment transport. These processes, each a cornerstone of sustainability, can directly compete for available water, and the by-products of one use (e.g. pollution) can affect others (e.g. drinking water and habitat). Importantly, unpredictable disturbances such as floods are central to healthy ecosystems but can pose threats to human settlements and livelihoods. People’s understandable proclivity to create stability in their environments has effects that ripple through entire regional landscapes, affecting not only biodiversity and the provision of important ecosystem services but often creating unintended feedbacks that increase risk (e.g. of floods and wildfire), and reduce the very stability that was sought. Finally, although cities are located along discrete sections of rivers, hydrological processes propagate over long distances of the river continuum, and their management is further complicated by connections between surface water and ground water, and by the myriad ways in which land management across entire watersheds affects water quality and quantity, including river flow regimes.
The ways in which we produce food and supply water for urban populations require enormous amounts of energy, as do other consumptive uses concentrated in and around cities, including transportation, and residential, commercial and industrial activities. Globally, cities use three-quarters of all energy produced, and discharge a similar proportion of carbon emissions. Importantly, the sources of energy used and the ways to generate and distribute it significantly influence city-landscape relationships, and the socioeconomic and ecological impacts of energy use. Each energy source — coal, oil, nuclear, wind, solar, wave and tidal power — comes with its own impacts and shortcomings. Each presents tradeoffs among factors such as greenhouse gas (GHG) emissions, threats to terrestrial and marine ecosystems, risks of disasters, source impacts of extraction and production, health and justice impacts on vulnerable human populations, and complete life cycle costs. In response to these challenges, there is an emerging emphasis on technologies, policies and urban design that combine distributed energy systems, conservation, and biological processing to reduce the demand for centrally distributed energy. Distributed energy systems generate energy on-site using renewable resources (e.g. solar cells on rooftops) and can be aggregated within urban power grids. Walkable, mixed-use neighborhoods combined with mass transit systems can reduce transportation costs and emissions, while improving the quality of urban life. Urban and peri-urban agriculture provide healthy, local food with reduced energy for processing and transportation. “Green” infrastructure such as urban forests, green roofs and biofiltration systems harness ecological mechanisms to conserve energy, and to cleanse and infiltrate urban runoff with greater adaptability and lower costs than traditional piped systems. Each of these solutions carries its own challenges of matching promises with performance, learning from experience, and hidden environmental, social and economic costs that only emerge with implementation.
The management of interconnected and geographically situated processes such as those associated with food, water and energy, is thus a cornerstone of creating cities that are sustainable, fulfilling, and just. Many key issues and attributes of such cities, for example habitat and health, are only partially addressed under a listing of keystones such as those described above, and the three presented are not intended as a comprehensive umbrella for all issues. The challenges are complex and fit the definition of “wicked” problems with no permanent solutions but only temporary resolutions. Yet the potential to build enduring urban systems that better meet the long-term needs of people and ecosystems is clear. The principles, systems and standards we establish in this time of global transformation could resonate for centuries to come.