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61.
Australian state and territory fire authorities advise residents to make a decision to prepare, stay and defend their properties from bushfires or leave well before the fire arrives in their area. The ‘Stay and defend or leave early’ policy is underpinned by strong evidence that well-prepared houses can be successfully defended and that late evacuation is a dangerous strategy. This paper presents the results of a study of the policy's implementation during the 2003 bushfires in North East Victoria and East Gippsland. Results suggest that despite high levels of awareness and support for the policy, there is some confusion over what it means to ‘stay and defend’ and ‘leave early’.  相似文献   
62.
ABSTRACT

It is the promise of smart grids – their anticipated role in meeting economic, social, environmental policy objectives – that is driving action on smart grids worldwide, while the reality is rather more messy. This paper is about the implementation of smart grids in Australia, and examines the degree to which environmental and social promises have materialised (or not) within two large energy smart grid initiatives undertaken in the period 2009–2014: the federal government-sponsored Smart Grid Smart City Program and the State of Victoria’s Advanced Metering Infrastructure Program. The analysis draws on a governmentality approach to examine how the promise of smart grids has not for the most part been delivered, concentrating in particular on how new digital technologies have not “behaved” in the way originally planned. Within a governmentality framework, it is generally assumed that technologies work to support government programmes, to accomplish governance. But growing evidence points to smart grid technologies undermining the promise of smart grids. Such a finding stands at odds with the assumption in governmentality about technologies doing work in consort with rationalities of government.  相似文献   
63.
The purpose of this study is to shed light on the connection between income, dwelling type, tenure type and city living, in terms of both a household’s energy saving behaviours and direct residential energy consumption. This study employs data from the Household Energy Consumption Survey, Australia. Using a seemingly unrelated regression (SUR) system of equations the results reveal some key mechanisms which may allow householders to realise lower levels of energy consumption and hence lower carbon emissions. The results indicate that there are characteristics unique to living in a city that are linked to higher levels of direct residential energy consumption. On a number of measures (e.g. household income, tenure type and dwelling type), the results point to a lower likelihood of engaging in energy saving behaviours in cities. Also, depending on the number of energy saving behaviours, these actions have the potential to more than offset higher direct residential energy consumption of householders residing in separate houses. Coupled with these findings renters, a more vulnerable social group, are found to be significantly disadvantaged, suffering from a much lower adaptive capacity. Specifically, householders who rent their home are 77% less likely to have solar electricity. A result which may reflect differences in access to opportunity. Further, householders who rent are less likely to engage in energy saving actions. A finding which may reflect difference in ontological security and the greater psychological burden associated with undertaking energy saving behaviours (a barrier) borne by renters not shared with home owners.  相似文献   
64.
Climate change mitigation and air quality management are mostly addressed separately in South African legal acts and policies. This approach is not always coherent, especially in the context of other serious issues South Africa is facing, such as poverty alleviation. Policies implemented to mitigate climate change might increase negative health affects due to unanticipated outcomes (e.g. increased local air pollution), and these indirect consequences must therefore be taken into account when devising mitigation strategies. However, greenhouse gas mitigation policies can also have co-benefits and positive impacts on local air pollution. An evidence-based approach that takes into account greenhouse gas emissions, ambient air pollutants, economic factors (affordability, cost optimisation), social factors (poverty alleviations, public health benefits), and political acceptability is needed tackle these challenges. A proposal is made that use of an integrated climate/air pollution techno-economic optimising model, such as the Greenhouse Gas and Air Pollution Synergies (GAINS) model, may provide a rational decision support tool to guide policy makers into effective strategies for combined Climate Change and Air Quality mitigation measures.  相似文献   
65.
Eucalyptus forest; and in the composition of understorey herbs, sedges, and grasslands. Pollen concentration and charcoal and organic content also exhibit post-European changes. Thus, pollen analysis provides a technique for determining changes in sediment budgets and identifying major vegetation changes in floodplains.  相似文献   
66.
Abstract: Habitat fragmentation is a severe threat to tropical biotas, but its long‐term effects are poorly understood. We evaluated longer‐term changes in the abundance of larger (>1 kg) mammals in fragmented and intact rainforest and in riparian “corridors” in tropical Queensland, with data from 190 spotlighting surveys conducted in 1986–1987 and 2006–2007. In 1986–1987 when most fragments were already 20–50 years old, mammal assemblages differed markedly between fragmented and intact forest. Most vulnerable were lemuroid ringtail possums (Hemibelideus lemuroides), followed by Lumholtz's tree‐kangaroos (Dendrolagus lumholtzi) and Herbert River ringtail possums (Pseudocheirus herbertensis). Further changes were evident 20 years later. Mammal species richness fell significantly in fragments, and the abundances of 4 species, coppery brushtail possums (Trichosurus vulpecula johnstoni), green ringtail possums (Pseudochirops archeri), red‐legged pademelons (Thylogale stigmatica), and tree‐kangaroos, declined significantly. The most surprising finding was that the lemuroid ringtail, a strict rainforest specialist, apparently recolonized one fragment, despite a 99.98% decrease in abundance in fragments and corridors. A combination of factors, including long‐term fragmentation effects, shifts in the surrounding matrix vegetation, and recurring cyclone disturbances, appear to underlie these dynamic changes in mammal assemblages.  相似文献   
67.
Environmental dredging is a primary remedial option for removal of the contaminated material from aquatic environment. Of primary concern in environmental dredging is the effectiveness of the intended sediment removal. A 5-year field monitoring study was conducted to assess the effectiveness of the environmental dredging in South Lake, China. The concentrations of total nitrogen (TN), total phosphors, and heavy metals (Zn, Pb, Cd, Cu, Cr, Ni, Hg, and As) before and after dredging in sediment were determined and compared. Multiple ecological risk indices were employed to assess the contamination of heavy metals before and after dredging. Our results showed that the total phosphorus levels reduced 42% after dredging. Similar changes for Hg, Zn, As Pb, Cd, Cu, Cr, and Ni were observed, with reduction percentages of 97.0, 93.1, 82.6, 63.9, 52.7, 50.1, 32.0, and 23.6, respectively, and the quality of sediment improved based on the criterion of Sediment Quality Guidelines by USEPA and contamination degree values (Cd) decreased significantly (paired t-test, p < 0.05). Unexpectedly, the TN increased 49% after dredging compared to before dredging. Findings from the study demonstrated that the environmental dredging was an effective mechanism for removal of total phosphorus and heavy metals from South Lake. Nevertheless, the dredging was ineffective to remove total nitrogen from sediment. We conclude that the reason for the observed increase in TN after dredging was likely ammonia release from the sediment impairing the dredging effectiveness.  相似文献   
68.
针对快速城镇化区域产业快速发展、人口高度密集与排水设施建设滞后间的突出矛盾,以苏州官渎里区域的典型重污染河道——官渎花园内河为研究对象,在分析区域排污特征的基础上,系统总结点污染源、面污染源和内污染源在该类区域的具体表现形式和影响因素,对各类污染物入河量进行调查测算.根据测算结果,官渎花园内河的CODcr、NH3-N、TN和TP年入河量分别为222.54、11.16、16.63和2.56t·a-1.对各污染源贡献率的分析结果表明,工业污染和生活污染为主要污染源,其次为降雨径流污染.在上述测算分析的基础上,结合苏南快速城镇化区域发展特点,提出了若干河道污染控制的对策与建议.  相似文献   
69.
Abstract: The cane toad (Bufo marinus), a large, toxic, American anuran, was introduced to Australia in 1935. Populations of many of Australia's reptiles (snakes, varanid lizards, crocodiles) and carnivorous mammals (dasyurid marsupials) have declined because these predators are killed by the toad's powerful toxins. In contrast to these well‐studied species, little is known about the cane toads impacts on Australian birds. We reviewed published and unpublished data on behavioral interactions between Australian avian predators and cane toads and collated distributional and dietary information to identify avian taxa potentially at risk from cane toad invasion. Cane toads are sympatric with 172 frog‐eating bird species in Australia, and an additional 8 bird species overlap with the predicted future range of the toad. Although many bird species thus are potentially at risk, behavioral observations suggest the risk level is generally low. Despite occasional reports of Australian birds being killed when they ingest cane toads, most birds either ignore toads or survive the predation event. The apparently higher tolerance of Australian birds to toad toxins, compared with Australian reptiles and marsupials, may reflect genetic exchange between Australian birds and Asian populations that encounter other bufonid species regularly and hence have evolved the capacity to recognize or tolerate this toxic prey.  相似文献   
70.
为了解不同植被类型土壤水资源的变化规律,选择南水北调中线水源区宁陕县寨沟区域典型植被针阔混交林、针叶林、板栗林、灌木林、荒坡草地和坡耕地为研究对象,通过样地调查与实验分析的方法对其土壤水分物理特征及有机质含量进行测定研究。结果表明,各种有林地的土壤容重、孔隙度和有机质等理化特征均优于荒坡和坡耕地;针阔混交林土壤含水量最高,蓄水能力明显好于其它植被类型;在垂直剖面上,各种植被类型坡地土壤含水量和饱和蓄水量随土壤深度的增加基本呈递减趋势,但有林地下降幅度较大,表层含水量明显高于荒坡与坡耕地表层。由此可见,在涵养水源方面,针阔混交林最好,针叶林、板栗林与灌木林次之,荒坡与坡耕地较差。  相似文献   
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