Environmental indicators for Australian cities: report on the 1997 national State of Environment study on human settlement indicators

State of the Environment Australia 1996 (SOEAC, 1996) represents the most comprehensive attempt, to date, of reporting on the condition of Australia's natural and built environments. Human Settlements (Newman et al., 1996) was selected as the first substantive chapter in this 500 page report in part because human settlements constitute a significant 'environment' in their own right as well as impacting pervasively upon Australia's natural environment (as represented by the atmosphere, land resources, biodiversity, inland waters, estuaries and marine). This dual characteristic of human settlements is reflected in the set of environmental indicators being developed as part of the present phase of the SOE Reporting process (Newton et al., 1998). In the 1996 Report, Australia's urban, rural and remote settlements were each examined separately in the context of their own characteristic 'environmental' pressures, states and responses (P-S-R). In the present phase of SOE reporting, a set of key and core indicators of human settlements are being sought that represent P-S-R at a range of spatial scales in the urban hierarchy. In this paper we explore the underpinning concepts, frameworks and models that are being employed in developing environmental indicators for human settlements in contemporary Australia. An over-arching concern is that indicators reflect a thorough understanding of the systems they are to monitor. In this regard, the extended metabolism model acts as a highly useful conceptual representation of human settlements, in that it is both descriptive-identifying the primary domain areas of urban systems such as energy, transport, housing, etc., which key indicators are developed-and normative-specifying desired directions for future urban development.