Search

Defining sustainable cities is not straightforward. The main issues involved in urban sustainability are buildings, energy, food, green areas and landscape, mobility, urban planning, water and waste; and their improvement is promoted through different strategies. However, a quantitative method, such as life cycle thinking (LCT), is essential to evaluating these strategies. This paper reviews LCT studies related to urban issues to identify the main research gaps in the evaluation of these improvement strategies. The review identifies the main sustainability strategies associated with each urban issue and compiles articles that deal with these strategies through LCT, including environmental life cycle assessment (LCA), life cycle costing (LCC), social LCA (S-LCA) and life cycle sustainability assessment (LCSA), as well as integrated analyses with combined tools. Water, waste and buildings are the urban issues that accounted for a larger amount of studies. In contrast, a limited number of papers assessed urban planning and energy (excluding energy in buildings). Strong interrelations among urban issues were identified, most of them including water. In terms of methods, 79% of the studies exclusively applied life cycle tools (i.e., LCA, LCC, S-LCA or LCSA). Within this group, the environmental dimension was the focus of 84% of the papers. Single environmental indicators (e.g., global warming) were common in 20% of the analyses, highlighting the need to integrate more impact categories to prevent trade-offs. In the field of social and sustainability assessment, there is a need for methodological advances that foster their application in urban areas. Further research should cover the thematic and methodological gaps identified in this paper, such as developing models that assess complex urban issues, generating comprehensive LCT studies and promoting multi-indicators. Life cycle tools might benefit from revising the methodology with stakeholders to optimize the understanding and communication of life cycle results for policy- and decision-making processes. [ABSTRACT FROM AUTHOR]

Abstract: Evidence on the role of information and knowledge for policy making shows that policy actors seldom use information as a direct input to their decisions. Similar patterns of (non)use have been identified in the case of indicators in the environmental and sustainable development policy domains. The objective of the paper is to elucidate the patterns of environmental indicator use and to argue for the introduction of a ‘politics of policy indicators’. With a limited set of characteristics (e.g. legitimacy, credibility and salience) of indicators, which help to apprehend the usability of indicators, we argue that the usability profile of indicators can be analysed as a matter of construction and deliberation by indicator creators and policy actors. The performance of indicators as policy tools – as rendered with their usability profile – is co-dependent of the institutional embeddedness of the indicators. Our conclusion makes the case that if environmental improvements towards more sustainability are partly relying on the quality and uptake of information into policy processes in order to steer decisions, then the ‘usability profile’ of indicators itself should be subject to collective and conscious steering. This call to ‘steer the steering’ is supported by the wider calls to initiate patterns of ‘reflexive governance’ within the sustainability policy domain. [Copyright &y& Elsevier]

Abstract: The development of systemic environmental monitoring and indicators for sustainability requires one to tackle the complexity of human–environmental systems. To this end the ecosystem approach is proposed here as a framework and the ecological network analysis as a tool for investigation while an urban system, represented as a water flow network, is discussed as a case study. Flow distribution is used to calculate total system throughput, development capacity, average mutual information, ascendency and overhead. These indices condense the complexity of the flow structure (representing system''s metabolism) into a few measures that provide information on how systems grow and develop; because of this they are consistent with the sustainability context. Two alternative scenarios are presented to discuss the effects of management actions (policies) on sustainability as they change the flow structure and system level indices. While it is shown that increasing system activity (intensity of processes) augments potential for development but not realized development, actions that improve the organization of flows, thus increasing average mutual information, may reduce total system throughput and drive the system toward more sustainable conditions. System level indices are holistic measures that unveil the relation between internal processes and whole system performance. Understanding this relation is crucial because the former are the target of environmental policies but sustainability, the objective of such policies, is an overall system trait. Because of these features system level indices can be examples of a new quality of indicators for sustainability assessment. [Copyright &y& Elsevier]