Managing urban riverscapes: An assessment framework to integrate social-ecological values and physical processes.

The services that rivers provide and how they affect the landscape plays a dominate role in urban planning and development. Urban riverscapes, which consist of stream channels, their floodplains, biotic communities, and manmade features, are complex social-ecological and hydrogeomorphic systems. Yet, despite recognition of their place and value, rivers are often degraded in urban settings. Successfully managing urban riverscapes requires improved methods to assess them and to more effectively link stressors to values, and to incorporate these considerations in planning. Assessment of urban riverscapes' physical condition and function-a hydrogeomorphic assessment-is necessary to make these links, and inform more appropriate management strategies for sustainable and valued riverscape systems. The framework and methods used for such an assessment should be appropriate to the urban context, insofar as they are applicable to a range of streams from lightly degraded to highly utilized or constructed. Above all, the framework must prioritize the connection of human communities to riverscapes. In this article, we outline a framework for urban riverscape assessment which considers four facets of urban riverscapes: human values, hydrology, geomorphology, and ecology. The four facets, assessed across multiple nested scales, provide a flexible basis for context-driven hydrogeomorphic assessment, which is vital to informing better planning and management of urban riverscapes. The framework can be integrated with other facets (e.g. geochemical, aquatic ecology) depending on the scope of the assessment. By linking intrinsic, relational, and use-based values to physical conditions, watershed managers can select relevant and measurable indicators that directly inform interventions in the riverscape, catchment, or urban zones to improve riverscape function and urban vitality through planning mechanisms. This assessment framework facilitates dialogue between managers, practitioners, scientists, and the community; enabling technical and non-technical inputs to the development of assessment criteria, and a shared vision to inform targets and goals.

Environmental arsenic, cadmium and lead dust emissions from metal mine operations: Implications for environmental management, monitoring and human health.

Although blood lead values in children are predominantly falling globally, there are locations where lead exposure remains a persistent problem. One such location is Broken Hill, Australia, where the percentage of blood lead values >10 µg/dL in children aged 1-4 years has risen from 12.6% (2010), to 13% (2011) to 21% (2012). The purpose of this study was to determine the extent of metal contamination in places accessible to children. This study examines contemporary exposure risks from arsenic, cadmium, lead, silver and zinc in surface soil and dust, and in pre- and post-play hand wipes at six playgrounds across Broken Hill over a 5-day period in September 2013. Soil lead (mean 2,450 mg/kg) and zinc (mean 3,710 mg/kg) were the most elevated metals in playgrounds. Surface dust lead concentrations were consistently elevated (mean 27,500 µg/m(2)) with the highest lead in surface dust (59,900 µg/m(2)) and post-play hand wipes (60,900 µg/m(2)) recorded close to existing mining operations. Surface and post-play hand wipe dust values exceeded national guidelines for lead and international benchmarks for arsenic, cadmium and lead. Lead isotopic compositions ((206)Pb/(207)Pb, (208)Pb/(207)Pb) of surface dust wipes from the playgrounds revealed the source of lead contamination to be indistinct from the local Broken Hill ore body. The data suggest frequent, cumulative and ongoing mine-derived dust metal contamination poses a serious risk of harm to children.

Things we can do now that we could not do before: Developing and using a cross-scalar, state-wide database to support geomorphologically-informed river management.

A fundamental premise of river management is that practitioners understand the resource they are working with. In river management this requires that baseline information is available on the structure, function, health and trajectory of rivers. Such information provides the basis to contextualise, to plan, to be proactive, to prioritise, to set visions, to set goals and to undertake objective, pragmatic, transparent and evidence-based decision making. In this paper we present the State-wide NSW River Styles database, the largest and most comprehensive dataset of geomorphic river type, condition and recovery potential available in Australia. The database is an Open Access product covering over 216,600 km of stream length in an area of 802,000 km2. The availability of the database presents unprecedented opportunities to systematically consider river management issues at local, catchment, regional and state-wide scales, and appropriately contextualise applications in relation to programs at other scales (e.g. internationally)-something that cannot be achieved independent from, or without, such a database. We present summary findings from the database and demonstrate through use of examples how the database has been used in geomorphologically-informed river management. We also provide a cautionary note on the limitations of the database and expert advice on lessons learnt during its development to aid others who are undertaking similar analyses.