.|  BES Theory Described

The emerging paradigm of sustainability in urban systems worldwide is signaled by policies enacted by specific cities, counties, regions, and states (e.g., UNEP 2005, Williams 2007). In BES III, the sustainability paradigm is reflected in sustainability plans aimed at adapting to changing environmental, social, and economic conditions in the city, counties, and state we study (i.e., Baltimore City 2009, Baltimore County 2010). Such plans themselves have become part of the changing local and regional context of city-suburban-exurban (CSE) systems, and like climate change, economic globalization, regional and international migration, and other large forcing functions (Grimm et al. 2008, Boone & Modarres 2006), they must be taken into account in understanding the ecology of CSE systems.
 
The paradigm of sustainability must be operationalized by specific adaptive environmental, social, and economic actions. Adaptation is the process, action, or outcome in a system in order for the system to better cope with, manage, and adjust to some changing condition, stress, hazard, risk, or opportunity (Smit & Wandel 2006). Such adaptive processes underlie the ability of a socio-ecological system to experience perturbations, shocks, and novel inputs and still remain in a given domain that is functionally viable (Smit & Wandel 2006, Nelson et al. 2007). These processes allow the system to respond to alterations in a way that retains the overall structure, functional processes, and resilience (Folke 2006, Nelson et al. 2007, Chapin et al. 2009). Adaptation and resilience are both evolutionary concepts, which recognize that fixed stability is unlikely in coupled biological and social systems (Gunderson 2000, Holling & Gunderson 2002, Chapin et al., 2009).
 
To investigate processes of adaptation to urban sustainability policies and to climate change, it is necessary to ask who adapts; to what; and how (Smit et al. 2000)? Adaptive actions are then characterized by scale, timing, form, purpose, and other dimensions (Smit et al. 1999, expanded by Fussel 2007). Significantly, these adaptive processes entail both planned processes, such as policy implementation, and autonomous processes such as locational choices at institutional and individual levels. In urban areas, these responses are shaped by multiple stresses; environmental, economic and social processes; rapidly evolving scientific understanding; dense infrastructure and technological legacies, and new policy pressures. This transition to greater sustainability and reduced climate vulnerability is expected to reveal both thresholds and tipping points in systems that constrain or accelerate adaptation (NSF ACERE 2009).
 
Within the context of evolving sustainability policy, BES identifies 1) locational choice and land change, 2) the degree of connectivity and dynamics of the urban river continuum and its watersheds, and 3) biotic metacommunity dynamics as three major areas of adaptation for empirical and modeling focus. These areas exploit theories new to the project, while connecting with our existing long-term research. We briefly introduce these areas and indicate cross connections between them and with adaptive processes.
 
Note: The citations referenced in the text above can be found here in the BES III proposal: http://beslter.org/products/besIII_proposal/BES_III_proposal_020110.pdf, with the exception of Chapin et al., 2009, which is as follows:
Chapin, F. S., III, S. R. Carpenter, G. P. Kofinas, C. Folke, N. Abel, W. C. Clark, P. Olsson, D. M. S. Smith, B. Walker, O. R. Young, F. Berkes, R. Biggs, J. M. Grove, R. L. Naylor, E. Pinkerton, W. Steffen, and F. J. Swanson. 2009. Ecosystem stewardship: sustainability strategies for a rapidly changing planet. Trends in Ecology and Evolution 25:241-249.