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211.
Environmental Science and Pollution Research - In 2008, the Mulberry River, a National Wild and Scenic River, was listed as impaired due to low pH (below pH 6.0). Over the last...  相似文献   
212.
The Murray–Darling Basin is Australia’s national food bowl, home to almost half of the national income from food production, as well as internationally significant wetlands, iconic red gum forests, endangered flora and fauna, and approximately 40 autonomous indigenous nations. Persistent severe drought and extreme flooding episodes have presented new challenges in the region. Chief among these challenges is the establishment of a legitimate framework to sustainably manage water resources that finds common ground between environmental, indigenous and commercial interests. A powerful approach to examine these processes is through the theory of diffusion and adaptation of policy innovations. Here, we describe an approach to place this theory on empirical ground using Q methodology. We elucidate patterns of subjectivity, to explore the perceptions of expert advice, subsidiarity and local knowledge to better understand the interests in play. We find that respect is held for local practitioners (water managers and farmers) and indigenous knowledge, but while policy innovations are being generated, the diffusion of policy is contested. We identify the potential, though limited, for common ground through substantive and respectful consultation.  相似文献   
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In this paper we describe the thermodynamic and kinetic basis for mineral storage of carbon dioxide in basaltic rock, and how this storage can be optimized. Mineral storage is facilitated by the dissolution of CO2 into the aqueous phase. The amount of water required for this dissolution decreases with decreased temperature, decreased salinity, and increased pressure. Experimental and field evidence suggest that the factor limiting the rate of mineral fixation of carbon in silicate rocks is the release rate of divalent cations from silicate minerals and glasses. Ultramafic rocks and basalts, in glassy state, are the most promising rock types for the mineral sequestration of CO2 because of their relatively fast dissolution rate, high concentration of divalent cations, and abundance at the Earth's surface. Admixture of flue gases, such as SO2 and HF, will enhance the dissolution rates of silicate minerals and glasses. Elevated temperature increases dissolution rates but porosity of reactive rock formations decreases rapidly with increasing temperature. Reduced conditions enhance mineral carbonation as reduced iron can precipitate in carbonate minerals. Elevated CO2 partial pressure increases the relative amount of carbonate minerals over other secondary minerals formed. The feasibility to fix CO2 by carbonation in basaltic rocks will be tested in the CarbFix project by: (1) injection of CO2 charged waters into basaltic rocks in SW Iceland, (2) laboratory experiments, (3) studies of natural analogues, and (4) geochemical modelling.  相似文献   
214.

Introduction

The effect of oceanic CO2 sequestration was examined exposing a deep-sea bacterium identified as Vibrio alginolyticus (9NA) to elevated levels of carbon dioxide and monitoring its growth at 2,750 psi (1,846 m depth).

Findings

The wild-type strain of 9NA could not grow in acidified marine broth below a pH of 5. The pH of marine broth did not drop below this level until at least 20.8 mM of CO2 was injected into the medium. 9NA did not grow at this CO2 concentration or higher concentrations (31.2 and 41.6 mM) for at least 72 h. Carbon dioxide at 10.4 mM also inhibited growth, but the bacterium was able to recover and grow. Exposure to CO2 caused the cell to undergo a morphological change and form a dimple-like structure. The membrane was also damaged but with no protein leakage.  相似文献   
215.
Approaches to biodiversity and catchment planning increasingly recognize the importance of the 'wider countryside' rather than the more site-specific focus of traditional environmental management programmes. Biodiversity depends on the viability of ecosystems across the whole countryside, and not only in designated reserves; equally, the quantity and quality of inland waters reflect overall conditions within river catchments, as well as the hydrological conditions of specific river channels. However, planning of these wider areas involves partnerships and agreements between a range of actors, which generally must be negotiated on a consensual basis and are vulnerable to subsequent dissent. This paper examines the actor-networks which have arisen in some innovative examples of 'wider countryside' planning and assesses their durability and contribution to the attainment of environmental objectives.  相似文献   
216.
This study advances the limited research on work alignment and work engagement by investigating how perceived alignment of job tasks and organizational strategic priorities (strategic alignment) influences work engagement. Measures of job control and work social support were also included to enable comparisons between strategic alignment and other well‐established job resources. A total of 1011 employees of an Australian state police service responded to three electronic, self‐report surveys. A reciprocal model was assessed over three waves of data, with varying time lags: 18 (Time 1 to Time 2), 12 (Time 2 to Time 3), and 30 months (Time 1 to Time 3). Longitudinal, reciprocal relationships were observed for work engagement and job control, strategic alignment, and colleague support. Work engagement also predicted supervisor support over time (reverse effect). This study demonstrated that, in addition to job resources, perceived alignment of job tasks and organizational priorities plays an important role in maintaining high levels of work engagement over time. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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Growing urbanisation causes pressures on many environmental assets such as groundwater systems, waterways, atmosphere, ecosystems and others. To manage and mitigate the negative effects of these pressures, environmental programs are typically launched, which comprise of eligible projects in different affected locations. The implementation of individual projects has a cost. However, due to budget constraints, most frequently not all suggested projects can be implemented which makes necessary to choose a subset. In this paper, we use a cost utility approach and a subsequent combinatorial optimisation based on metaheuristics to determine a project portfolio which returns a maximum aggregated utility while keeping the budget constraint. To ensure that the mutual exclusiveness of projects at one particular site is guaranteed, we further developed the employed metaheuristics. We apply this approach within a waterway health program in a river catchment in Brisbane, Australia, and compare its results to a commonly used selection process that does not involve combinatorial optimisation. We find that the use of combinatorial optimisation leads to a considerable improvement of the selection process and can help to more effectively allocate environmental expenditure.  相似文献   
220.
Environmental Chemistry Letters - Gene delivery is the process of introducing foreign genetic material, such as DNA or RNA, into host cells. Gene...  相似文献   
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