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Fiona Miller Annie Bolitho Natalie Jamieson Charlotte Catmur Anna Hurlimann Kathryn Bowen 《The Australian geographer》2014,45(1):19-35
Drawing upon theory from the field of urban political ecology, we analyse a major strategic water plan for Melbourne, Australia—the Sustainable water strategy for the Central Region, published in 2006. We assess the extent to which the strategy identified and addressed ecological sustainability in terms of: cultural frames; ecological context; social equity; and engagement processes. We identify that the strategy's framing of water was largely separate from its social and ecological context. This framing resulted in the importance of issues such as environmental flows, social equity and cultural values being diminished, thus avoiding the inevitable confrontation with environmental limits needed to ensure long-term ecological sustainability. Our analysis shows that the discursive dominance of economics limited the response to persuasive scientific arguments for greater ecological consideration in the strategy. Our findings suggest that broadening engagement with the diverse ways in which water is valued is likely to contribute to more equitable and ecologically sustainable water futures. 相似文献
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Temperature response to future urbanization and climate change 总被引:2,自引:0,他引:2
Daniel Argüeso Jason P. Evans Lluís Fita Kathryn J. Bormann 《Climate Dynamics》2014,42(7-8):2183-2199
This study examines the impact of future urban expansion on local near-surface temperature for Sydney (Australia) using a future climate scenario (A2). The Weather Research and Forecasting model was used to simulate the present (1990–2009) and future (2040–2059) climates of the region at 2-km spatial resolution. The standard land use of the model was replaced with a more accurate dataset that covers the Sydney area. The future simulation incorporates the projected changes in the urban area of Sydney to account for the expected urban expansion. A comparison between areas with projected land use changes and their surroundings was conducted to evaluate how urbanization and global warming will act together and to ascertain their combined effect on the local climate. The analysis of the temperature changes revealed that future urbanization will strongly affect minimum temperature, whereas little impact was detected for maximum temperature. The minimum temperature changes will be noticeable throughout the year. However, during winter and spring these differences will be particularly large and the increases could be double the increase due to global warming alone at 2050. Results indicated that the changes were mostly due to increased heat capacity of urban structures and reduced evaporation in the city environment. 相似文献
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Organic carbon in estuarine sediments can have many different sources. Terrestrial, riverine, estuarine and marine C pools may all contribute to and influence the organic C (Corg) inventory of the estuarine sediments and the differing stable isotope signatures of the sources are reflected in the sediment's overall 13C content. Ecological interpretations of sedimentary isotope data may, however, be limited by the fact the total Corg inventory of a sediment may not be an accurate representation of the fraction that is labile and being actively turned over by the sedimentary community. To gain a better understanding of sedimentary Corg dynamics in estuaries and the relationship between the sedimentary C pool and the Corg undergoing mineralisation, we studied three components of an estuarine system: (1) the sedimentary Corg inventory on a transect from the mouth to the upper end of the estuary, (2) temporal changes of sedimentary Corg at one station throughout a year, and (3) the δ13C of respired CO2 compared to the δ13C of available source material and sedimentary Corg in a novel application of methods developed for soil science. Our experiments demonstrated that material of marine origin dominated the studied estuary. At the time-series station, material of marine origin dominated the sedimentary Corg throughout the 1-yr study period. δ13C values of CO2 released from the sediment differed significantly from the sedimentary Corg inventory at all study sites, but also clearly reflected differences between the main sections of the estuary. These results suggest that δ13C measurements of respired CO2 are promising as a tool to advance our understanding of C cycling in estuaries, and highlight that the sedimentary Corg pool alone may not be a satisfactory indicator of OM utilisation in estuarine sediments. 相似文献
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Institutional capacity is an important element for climate change adaptation (CCA) and the development of such capacity is a great challenge in a Least Developed Country like Cambodia where resources are limited. An important first step to increasing capacity is via an understanding of the level of existing capacity; future priorities can then be subsequently identified. This study aimed to assess the capacity of organizations to implement climate change activities in Cambodia in order to provide such a basis for building capacity. Four elements of capacity were investigated in this research: (1) financial resources, (2) cooperation and coordination of stakeholders, (3) availability and quality of information on vulnerability and adaptation to climate change, and (4) the level of understanding of climate change vulnerability and adaptation. The data were collected through semistructured interviews with a wide range of government and non-government informants across a number of sectors. Results of the study showed that informants perceived capacity for CCA to be very constrained, especially in terms of financial resources and cooperation, and addressing these factors was ranked as the highest climate change capacity priority. Institutional capacity constraints were considered to relate more generally to weak governance of CCA. In light of our research findings, the absence of local higher education institutions in CCA activities should be addressed. The support of such institutions would provide an important mechanism to progress both capacity development as well as partnerships and coordination between different types of organizations and relevant sectors.Policy relevanceCapacity for CCA within Cambodian health and water sectors was perceived to be very constrained across a range of interdependent factors. Increasing funding was ranked as the highest priority for building capacity for CCA; however, governance factors such as ‘improved cooperation’ were also ranked highly. Improving stakeholders' awareness of the availability of adaptation funds and resources, and their responsiveness to funding criteria, is an important implication of our research, as is improving the mobilization of local resources and the private sector. To address the issue of weak cooperation among stakeholders, improving the coordination function of the National Climate Change Committee (NCCC) regarding stakeholder engagement and capacity building is crucial. Ensuring that CCA activities are based on sound information and knowledge from across different disciplines and, importantly, include the perspectives of vulnerable people themselves, ultimately underpins and supports the realization of the above priorities. 相似文献
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Summary results from a pilot study conducted around an oil production platform on the Northwest Shelf of Australia 总被引:3,自引:0,他引:3
King SC Johnson JE Haasch ML Ryan DA Ahokas JT Burns KA 《Marine pollution bulletin》2005,50(11):1163-1172
The Australian Institute of Marine Science (AIMS) conducted a pilot study around the Harriet A oil production platform on the Northwest Shelf of Australia. We evaluated hepatic ethoxyresorufin-O-deethylase (EROD) activity, fluorescent aromatic compounds (FACs) in bile and immunodetection of CYP1A-like proteins in two Australian tropical fish species, Gold-Spotted Trevally (Carangoides fulvoguttatus) and Bar-Cheeked Coral Trout (Plectropomus maculatus) to assess exposure to petroleum hydrocarbons associated with produced formation water (PFW). Additionally, the incidence of hydrocarbon-degrading bacteria isolated from the liver and bile of all fish captured was examined. Low EROD activity was found in both species, with EROD activity in C. fulvoguttatus showing significant site differences. FACs and CYP1A protein levels in C. fulvoguttatus showed a clear trend in hydrocarbon exposure consistent with hydrocarbon chemistry data: Harriet A>Harriet C>reference site. P. maculatus showed elevated levels of FACs at Harriet A as compared to the reference site and demonstrated detectable levels of CYP1A-like proteins at these two sites. Hydrocarbon-degrading bacteria were found in the liver and bile of both species, yet there was no correlation by sites. Our results demonstrate that C. fulvoguttatus and P. maculatus have potential as indicator species for assessing the effects from exposure to petroleum hydrocarbons. Both FACs and CYP1A are providing warning signs that there is potential for biological effects on fish populations exposed to PFW around the Harriet A production platform. 相似文献