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721.
Using adaptive governance to rethink the way science supports Australian drought policy 总被引:4,自引:0,他引:4
In this paper we show how ideas from a longstanding but little recognised literature on adaptive governance can be used to rethink the way science supports Australian drought policy. We compare and contrast alternative ways of using science to support policy in order to critique traditional commentary on Australian drought policy. We find that criticism from narrow disciplinary and institutional perspectives has provided few practical options for policy makers managing these complex and interacting goals. In contrast, ideas from a longstanding but little recognised literature on adaptive governance have potential to create innovative policy options for addressing the multiple interacting goals of Australian drought policy.From an adaptive governance perspective, the deep concern held by Australian society for rural communities affected by drought can be viewed as a common property resource that can be sustainably managed by governments in cooperation with rural communities. Managing drought assistance as a common property resource can be facilitated through nested and polycentric systems of governance similar to those that have already evolved in other arenas of natural resource management in Australia, such as Landcare groups and Catchment Management Authorities. Essential to delivering these options is the creation of flexible, regionally distributed scientific support for drought policy capable of integrating local knowledge and informing the livelihood outcomes of critical importance to governments and rural communities. 相似文献
722.
We describe the first known embryo of a neoceratopsian dinosaur, perhaps the most ubiquitous Laurasian group of Cretaceous dinosaurs, which is preserved completely enclosed within an egg. This specimen was collected from Late Cretaceous beds of southern Mongolia, which commonly preserve fossils of the neoceratopsian, Yamaceratops dorngobiensis. The small egg was scanned using high-resolution X-ray computed tomography and digitally prepared from the matrix. The preserved and imaged elements support a diagnosis of the embryo to Neoceratopsia and allow preliminary observations of ontogenetic transformations within this group. The addition of an embryo also adds another important data point to the already impressive postnatal ontogenetic series that are available for this clade. 相似文献
723.
Lindsay C. Stringer Jen C. Dyer Mark S. Reed Andrew J. Dougill Chasca Twyman David Mkwambisi 《Environmental Science & Policy》2009,12(7):748-765
The impacts of climate change, drought and desertification are closely interlinked, and most acutely experienced by populations whose livelihoods depend principally on natural resources. Given the increases in extreme weather events projected to affect the Southern Africa region, it is essential to assess how household and community-level adaptations have been helped or hindered by institutional structures and national policy instruments. In particular, there is a need to reflect on efforts related to the United Nations’ environmental conventions to ensure that policies support the maintenance of local adaptations and help retain the resilience of socio-economic and environmental systems. This paper examines three interlinked drivers of adaptation: climate change, desertification and drought, assessing the extent to which international and national policy supports local adaptive strategies in three countries in southern Africa. We show that while common ground exists between desertification and climate change adaptations at the policy level, they are insufficiently mainstreamed within broader development approaches. Similarly, there are some overlaps between policy-driven and autonomous local adaptations, but the mutually supportive links between them are poorly developed. Further efforts to integrate local adaptation strategies within policy could increase local resilience to environmental change, while also contributing to wider development goals. 相似文献
724.
Agricultural bio-char production,renewable energy generation and farm carbon sequestration in Western Australia: Certainty,uncertainty and risk 总被引:1,自引:0,他引:1
Mark P. McHenry 《Agriculture, ecosystems & environment》2009,129(1-3):1-7
Reducing the vulnerability of agriculture to climate change while increasing primary productivity requires mitigation and adaptation activities to generate profitable co-benefits to farms. The conversion of woody-wastes by pyrolysis to produce bio-char (biologically derived charcoal) is one potential option that can enhance natural rates of carbon sequestration in soils, reduce farm waste, and substitute renewable energy sources for fossil-derived fuel inputs. Bio-char has the potential to increase conventional agricultural productivity and enhance the ability of farmers to participate in carbon markets beyond traditional approach by directly applying carbon into soil. This paper provides an overview of the pyrolysis process and products and quantifies the amount of renewable energy generation and net carbon sequestration possible when using farm bio-waste to produce bio-char as a primary product. While this research provides approximate bio-char and energy production yields, costs, uses and risks, there is a need for additional research on the value of bio-char in conventional crop yields and adaptation and mitigation options. 相似文献
725.
Many organisms show differences between males and females in growth rate and crucial life history parameters, such as longevity.
Considering this, we may expect levels of toxic metabolic by-products of the respiratory chain, such as reactive oxygen species
(ROS), to vary with age and sex. Here, we analyse ROS levels in female Australian painted dragon lizards (Ctenophorus pictus) and their offspring using fluorescent probes and flow cytometry. Basal level of four ROS species (singlet oxygen, peroxynitrite,
superoxide and H2O2) measured with a combined marker, and superoxide measured specifically, varied significantly among families but not between
the sexes. When blood cells from offspring were chemically encouraged to accelerate the electron transport chain by mitochondrial
uncoupling, net superoxide levels were three times higher in daughters than sons (resulting in levels outside of the normal
ROS range) and varied among mothers depending on offspring sex (significant interaction between maternal identity and offspring
sex). In offspring, there were depressive effects on ROS of size-controlled relative clutch size, which relies directly on
circulating levels of vitellogenin, a confirmed antioxidant in some species. Thus, levels of reactive oxygen species varies
among females, offspring and in relation to reproductive investment in a manner that makes its regulatory processes likely
targets of selection. 相似文献
726.
Mann RE Adlaf E Zhao J Stoduto G Ialomiteanu A Smart RG Asbridge M 《Journal of Safety Research》2007,38(6):669-674
PROBLEM: This study examines the relationships between collision involvement and several measures of cannabis use, including driving after using cannabis, among drivers, based on a population survey of Ontario adults in 2002 and 2003. METHOD: Logistic regression analyses examined self-reported collision involvement in the last 12 months by lifetime use of cannabis, past year use of cannabis, and past year driving after using cannabis, while controlling for demographic characteristics. RESULTS: We found that the odds of reporting collision involvement was significantly higher among cannabis users, and among those who reported driving after cannabis use. Some evidence for a dose-response relationship was seen as well. DISCUSSION: Cannabis users and people who report driving after cannabis use are also more likely to report being involved in a collision in the past year. These observations suggest that collision prevention efforts could be aimed at these groups. Additional work to determine the causal pathways involved in the relationships observed here is needed. IMPACT ON INDUSTRY: None. 相似文献
727.
长期污水灌溉后林地土壤中磷的含量与移动 总被引:3,自引:1,他引:2
为尽可能地削减污水携带的N、P进入湖泊,处理后的城市生活污水被直接喷灌到新西兰罗托鲁阿市的Whakarewarewa森林,并建立了污水灌溉林地处理系统的长期定位试验地以评价生态系统对污水携带营养物质的同化能力.为查清长期污水灌溉土壤中P的数量、迁移淋失及其环境危机,对11a污水灌溉后火山灰土壤中磷的积累、再分布进行剖面分层采样测定.结果表明,土壤pH、TP、Olsen P、M3P、M3Ca和M3Mg在所有灌溉处理区的表层土壤(0~10 cm)均有显著(p0.05)增加,部分增加的显著性达到20~40 cm土层或更深层次土壤.大多数随灌溉而进入土壤的P被保存在上层土壤(0~40 cm)中.土壤Olsen P和M3P的浓度在中、高水平处理区的20 cm以上土层中超过了环境临界值(Olsen P为60 mg.kg-1;M3P为150mg.kg-1),磷饱和率(M3PSR)数值同时显示表层土壤对P的吸持已近饱和,预示土壤磷素有随下渗水向下移动的潜在可能.常规土壤采样以60 mg.kg-1 Olsen P测定值为环境临界值,可解决土壤剖面中磷的下移监测难题.以M3P与M3Al、M3Fe的摩尔比计算的磷饱和率(M3PSR)作为长期污水灌溉林地处理系统中土壤磷向下移动的环境危机临界值参数指标已不是很理想,对新的磷饱和参数的研究是今后的主要工作之一. 相似文献
728.
Australian owlet-nightjars (Aegotheles cristatus; ~50?g) are one of only a few avian species that roost in cavities year-round and regularly enter torpor. Cavity roosts act as thermal buffers, and roost type likely affects energy expenditure of small birds. We used radiotelemetry to locate diurnal winter roost sites of owlet-nightjars in central Australia and to measure body (T (b)) and skin (T (skin)) temperature. We also recorded ambient temperature inside (T (IN)) and outside roosts. Individual owlet-nightjars used one to seven different roosts (tracking time 3-10?weeks), selecting either rock crevices (four birds) or tree hollows (four birds), or switching between the two roost types (seven birds). Rock crevices (T (IN) +9°C to +33°C) were warmer and thermally more stable than tree hollows (T (IN) -4.0°C to +37°C). Torpor, often expressed by a reduction of T (skin)/T (b) by >10°C for 3-4?h at dawn, was influenced by roost selection; torpor use in tree hollows was almost twice that in rock crevices. Despite the potential energy savings accrued from roosting in well-insulated cavities, owlet-nightjars roosted in tree hollows more often (65% bird days, n?=?398) than in rock crevices (35% bird days, n?=?211). Lower costs of arousal from torpor via passive rewarming and basking and decreased risk of predation are two possible explanations for the preference to roost in tree hollows. We provide the first evidence for the influence of cavity roost selection on torpor use in a free-ranging bird and show that roost selection and thermal biology are strongly interrelated in determining energy expenditure. 相似文献
729.
With the increasing demand for fossil based energy and implementation of progressively strict environmental pollution control
standards, treatment of a large amount of co-produced waters (CPWs) from fossil based energy production has become increasingly
important. Removal of bicarbonate with H2SO4 has been recently studied as a simple and cost-e ective method to decrease the alkalinity
of CPWs. The present work investigates the kinetics of the reaction between H2SO4 and NaHCO3, which could provide the base for
scaling-up the CPW treatment technology. Based on the measured quantity change of the CO2 gas generated from the reaction between
H2SO4 and NaHCO3 with time under specified initial reaction conditions, the reaction orders with respect to H2SO4 and NaHCO3 were
determined. Experiments were also conducted within the temperature of 15–30°C to find various global rate coe cients of the reaction
to calculate the activation energy and the pre-exponential factor of the empirical Arrhenius form of the bicarbonate removal reaction,
which are 197.7 kJ/mol and 3.13 1034 (mol??3:7 L3:7 sec??1), respectively. 相似文献
730.
Slobodan Djordjevi? David Butler Philippe Gourbesville Ole Mark Erik PascheAuthor vitae 《Environmental Science & Policy》2011,14(7):864-873
In the context of urban flood management, resilience is equal to resisting, recovering, reflecting and responding. The variety of causes of flooding and their consequences underpin the need for increased and internationally coordinated efforts to enhance technologies and policies for dealing with floods. This paper addresses this issue and presents some novel research ideas related to resilience to flooding in urban areas, which are under development within the EU FP7 project ‘Collaborative research on flood resilience in urban areas’ (CORFU). The approach adopted in this project aims to quantify the cost-effectiveness of resilience measures and integrative and adaptable flood management plans for different scenarios of relevant drivers: urban development, socio-economic trends and climate changes. It is believed that the way in which the different models are being put together, combined with the variability of conditions in case study areas in Asia and in Europe, will ultimately enable more scientifically sound policies for the management of the consequences of urban flooding. 相似文献