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This paper describes the relatively new, university entry level examination offered by the International Baccalaureate Organisation in the subject of Environmental Systems. The programme has an integrated, holistic approach, and a strong international focus. The authors are Chief Examiner and Deputy Chief Examiner for this examination.  相似文献   
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This research is concerned with effects and actions at the local level, where it is argued that local governing processes are key to developing sustainable communities. The roles of the citizen and of formal government are changing such that the implementation of sustainability praxis at the local level requires that citizens and governments reconsider both the meaning and techniques of governance. Indeed, how we are governed, participate in governing processes and internalise and accept the need for change will affect how local communities make constant and lasting a dynamic praxis of sustainability. Actors in local governments and communities may be crucial in this task—especially as facilitators, enablers, leaders and partners. In this paper we focus on the Huon Valley Council and some members of one of its communities. We examine how they are experimenting with partnerships as a form of governance to unify, control, mobilise and regulate the conduct of various actors, and how such partnerships may foster sustainability praxis in the Valley's diverse communities of place and interest.  相似文献   
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Regionally specific sustainability processes that account for diverse environments and populations and that integrate social, economic, political and ecological spheres are being developed in Western Australia. A coordinated commitment to sustainability principles and a participatory philosophy by the state and local governments is necessary. This requires a transformation of the public service, from a director of passive programmes and laws to a facilitator of community projects and outcomes, towards an enabling state. An international participatory paradigm provides an array of concepts and methods for local and regional communities in partnership with government and industry to achieve this. Participatory methodologies are utilised successfully around the globe to create an institutional framework that facilitates a process of dialogue, partnership, networking, learning and managing change. This paper examines the potential contribution of a participatory approach to improve the participatory capacity of regional communities and both local and state governments towards the facilitation of regional sustainability processes.  相似文献   
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Headwater streams are critical components of the stream network, yet landowner perceptions, attitudes, and property management behaviors surrounding these intermittent and ephemeral streams are not well understood. Our research uses the concept of watershed disproportionality, where coupled social-biophysical conditions bear a disproportionate responsibility for harmful water quality outcomes, to analyze the potential influence of riparian landowner perceptions and attitudes on water quality in headwater regions. We combine social science survey data, aerial imagery, and an analysis of spatial point processes to assess the relationship between riparian landowner perceptions and attitudes in relation to stream flow regularity. Stream flow regularity directly and positively shapes landowners’ water quality concerns, and also positively influences landowners’ attitudes of stream importance—a key determinant of water quality concern as identified in a path analysis. Similarly, riparian landowners who do not notice or perceive a stream on their property are likely located in headwater regions. Our findings indicate that landowners of headwater streams, which are critical areas for watershed-scale water quality, are less likely to manage for water quality than landowners with perennial streams in an obvious, natural channel. We discuss the relationships between streamflow and how landowners develop understandings of their stream, and relate this to the broader water quality implications of headwater stream mismanagement.  相似文献   
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This paper reports mercury (Hg) concentrations and fluxes in precipitation that was collected from 2006 to 2008 at three sites in Canada: sub-Arctic boreal forest, sub-Arctic coast, and southern Alberta, using cold-adapted precipitation collectors which operated reliably at temperatures below ?30 °C during the study. The southern Alberta site (Crossfield) may be influenced by Calgary urban air, whereas the sub-Arctic coastal (Churchill, Manitoba) and boreal forest (Fort Vermilion, Alberta) sites are in more remote northern areas. Annual mean Hg concentrations in precipitation (5.0–9.2 ng L?1) at the study sites were in the lower half of the range reported for southern Canada and the USA by the Mercury Deposition Network (MDN). But owing to typically low precipitation rates, gross wet Hg fluxes (0.54–2.0 μg m?2 yr?1) were among the lowest reported by MDN, with Crossfield having about twice the flux in 2007 of the other two sites. Flux was significantly correlated with precipitation, and thus was highest in summer (June–August) and lowest during winter, a pattern typical of other temperate continental locations. There was no evidence of higher wet Hg fluxes or concentrations in springtime at Churchill where atmospheric mercury depletion events (AMDEs) occur. Measured gross deposition fluxes at the study locations were ~2–8 times lower than estimated by GEOS-Chem and GRAHM atmospheric models. The largest discrepancy occurred for Churchill, which raises the question of how well Hg deposition from AMDEs is described by current models. Better agreement between measurements and models was obtained from MDN stations in Alberta and Alaska, where wet Hg fluxes were 2–10 times higher than the study sites either because of power plant emissions (Alberta), or because of high precipitation rates (Alaska).  相似文献   
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Following the remediation of animal manure spills that reach surface waters, contaminated streambed sediments are often left in place and become a source for internal phosphorus (P) loading within the stream in subsequent flow. The objective of this study was to develop treatment rates and combinations of alum and CaCO(3) to mitigate P from contaminated sediments of different particle size distributions following a manure spill. Sediment specific alum and CaCO(3) treatment rates were developed based upon the resultant alum treatment ranges established for each sediment type. Clay loam sediments required 54% more alum to mitigate P desorption relative to sediments that contain at least 60% sand. Amending sediments with the highest rates of alum/alum + CaCO(3), resulted in a 98-100% reduction in P desorption and a similar water column pH for all sediments types. Observations from this study demonstrated the effectiveness of alum/alum + CaCO(3) to increase P retention in sediments following a manure spill.  相似文献   
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Mega-sites have a notable impact on surrounding ecological systems. At such sites there are substantial risks associated with complex socio-ecological interactions that are hard to characterize, let alone model and predict. While the urge to control and clean-up mega-sites (control and correct) is understandable, rather than setting a goal of cleaning up such sites, we suggest a more realistic response strategy is to address these massive and persistent sources of contamination by acknowledging their position as new features of the socio-ecological landscapes within which they are located. As it seems nearly impossible to clean up such sites, we argue for consideration of a 'coping with change' rather than a 'control and correct' approach. This strategy recognizes that the current management option for a mega-site, in light of its physical complexities and due to changing societal preferences, geochemical transformations, hydrogeology knowledge and remedial technology options may not remain optimal in future, and therefore needs to be continuously adapted, as community, ecology, technology and understanding change over time. This approach creates an opportunity to consider the relationship between a mega-site and its human and ecological environments in a different and more dynamic way. Our proposed approach relies on iterative adaptive management to incorporate mega-site management into the overall socio-ecological systems of the site's context. This approach effectively embeds mega-site management planning in a triple bottom line and environmental sustainability structure, rather than simply using single measures of success, such as contaminant-based guidelines. Recognizing that there is probably no best solution for managing a mega-site, we present a starting point for engaging constructively with this seemingly intractable issue. Therefore, we aim to initiate discussion about a new approach to mega-site management, in which the complexity of the problems posed by mega-sites is reflected upon in its entirety. These complexities are associated with uncertainties and unknowns that have to be addressed, as they have an impact on the strategies being developed and applied. We contend that the best that can be hoped for in mega-site management is an acceptable solution for the current state of affairs, with good flexibility to modify strategies as new site conditions, remediation possibilities, community preferences and management objectives develop over time.  相似文献   
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Armstrong, William H., Mathias J. Collins, and Noah P. Snyder, 2012. Increased Frequency of Low‐Magnitude Floods in New England. Journal of the American Water Resources Association (JAWRA) 48(2): 306‐320. DOI: 10.1111/j.1752‐1688.2011.00613.x Abstract: Recent studies document increasing precipitation and streamflow in the northeastern United States throughout the 20th and early 21st Centuries. Annual peak discharges have increased over this period on many New England rivers with dominantly natural streamflow – especially for smaller, more frequent floods. To better investigate high‐frequency floods (<5‐year recurrence interval), we analyze the partial duration flood series for 23 New England rivers selected for minimal human impact. The study rivers have continuous records through 2006 and an average period of record of 71 years. Twenty‐two of the 23 rivers show increasing trends in peaks over threshold per water year (POT/WY) – a direct measure of flood frequency – using the Mann‐Kendall trend test. Ten of these trends had p < 0.1. Seventeen rivers show positive trends in flood magnitude, six of which had p < 0.1. We also investigate a potential hydroclimatic shift in the region around 1970. Twenty‐two of the 23 rivers show increased POT/WY in the post‐1970 period when comparing pre‐ and post‐1970 records using the Wilcoxon rank‐sum test. More than half of these increases have p < 0.1, indicating a shift in flow regime toward more frequent flooding. Region wide, we found a median increase of one flood per year for the post‐1970 period. Because frequent floods are important channel‐forming flows, these results have implications for channel and floodplain morphology, aquatic habitat, and restoration.  相似文献   
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