Page - 414 - in Biodiversity and Health in the Face of Climate Change

414 18.1.2 Urban Complexity, Sustainability and  Governance The complexity of urban systems poses enormous challenges for sustainability in identifying causal mechanisms because of the many confounding variables that exist. At the same time, scientific findings from empirical studies are difficult to generalize due to variations in socio-economic and biophysical contexts, and the great heterogeneity that characterizes urban regions (Grimm et  al. 2008). Key chal- lenges are scale mismatches, cross-scale interactions and limited transferability across scales (Cumming et  al. 2012). Furthermore, the limited predictability of sys- tem behaviour over the long term requires a new consideration of uncertainty (Polasky et  al. 2011). The research and application of urban sustainability principles have until now rarely been applied beyond city boundaries and are often constrained to either single or narrowly defined issues (e.g. population, climate, energy, water) (Marcotullio and McGranahan 2007; Seitzinger et  al. 2012). Although local governments often aim to optimize resource use in cities, increase efficiency and minimize waste, cities can never become fully self-sufficient. Therefore, individual cities cannot be con- sidered ‘sustainable’ without acknowledging and accounting for their dependence on the natural ecosystems, resources and populations from other regions around the world (Folke et  al. 1997; Seitzinger et  al. 2012). Consequently, there is a need to revisit the concept of sustainability, as its narrow definition and application may not only be insufficient but can also result in unintended consequences, such as the ‘lock-in’ of undesirable urban development trajectories (Ernstson et  al. 2010). Governance failures and their negative outcomes can at least partly be under- stood as the result of a constrained ability and willingness to understand the dynam- ics of urban complexity. Governing dynamic complex urban systems for improving urban health and well-being, therefore, requires a better understanding of urban system complexity and the institutions that inhibit or enable solution-oriented actions (cf. Duit and Galaz 2008). The dynamics and temporality of changes of a system determine adaptive gover- nance styles. Under short-term shocks or longer-term stresses the styles of action can be control-oriented or adaptive (Fig.  18.1). Control-oriented styles of governance Fig. 18.1 Governance styles are determined by control and adaptive styles of action and how the temporality of system changes is perceived. (Modified from Leach et  al. 2010) T. Elmqvist et al.