Managing urban ecosystems for goods and services.
Concomitant with the rise in the proportion of the global human population that resides in urban areas has been growth in awareness of the importance of the provision of ecosystem goods and services to those people. Urban areas are themselves of significance in this regard because of their areal extent, and hence the quantity of services falling within their bounds, and because of the need for local provision of services to urban residents. Here, we review key challenges to the effective management of ecosystem goods and services within urban areas. These challenges include the structure of green space, its temporal dynamics, spatial constraint on ecosystem service flows, occurrence of novel forms of flows, large numbers of land managers, conflicting management goals, possible differences between perceptions of urban dwellers and the reality of the distribution and flow of ecosystem services, and the 'wicked' nature of the problem of ecosystem service management. Synthesis and applications. Urban areas present very particular combinations of challenges and opportunities for the management of ecosystem goods and services. The spatial and temporal heterogeneity of green spaces greatly complicates the maintenance and improvement in service provision as well as dramatically inflating costs. Spatial constraints on ecosystem service flows mean that these can be highly dependent on the maintenance of particular areas of connectivity, but also that provision of additional key points of connectivity may be disproportionately beneficial to those flows. The existence of novel forms of flows of ecosystem services in urban areas offers means of overcoming spatial constraints on more natural flows, but will require the development of new kinds of ecosystem process models to inform their design and management. The large numbers of land managers, conflicts between the best approaches for managing for different goods and services, and frequent differences between the perceptions of urban dwellers and the reality of urban landscapes create a complex management context. The management of ecosystem goods and services is closely allied to the challenges of conventional urban planning. However, applied ecology has a broad range of tools available to assist in determining solutions, including the use of high-resolution remote sensing techniques, landscape ecology principles and theory (e.g. patch and matrix frameworks, meta-population models), and systematic conservation planning approaches.