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911.
Michael J. Truex Christian D. Johnson James R. Spencer T. Prabhakar Clement Brian B. Looney 《补救:环境净化治理成本、技术与工艺杂志》2007,17(4):23-40
A US EPA directive and related technical protocol outline the information needed to determine if monitored natural attenuation (MNA) for chlorinated solvents is a suitable remedy for a site. For some sites, conditions such as complex hydrology or perturbation of the contaminant plume caused by an existing remediation technology (e.g., pump‐and‐treat) make evaluation of MNA using only field data difficult. In these cases, a deterministic approach using reactive transport modeling can provide a technical basis to estimate how the plume will change and whether it can be expected to stabilize in the future and meet remediation goals. This type of approach was applied at the Petro‐Processors Inc. Brooklawn site near Baton Rouge, Louisiana, to evaluate and implement MNA. This site consists of a multicomponent nonaqueous‐phase source area creating a dissolved groundwater contamination plume in alluvial material near the Mississippi River. The hydraulic gradient of the groundwater varies seasonally with changes in the river stage. Due to the transient nature of the hydraulic gradient and the impact of a hydraulic containment system operated at the site for six years, direct field measurements could not be used to estimate natural attenuation processes. Reactive transport of contaminants were modeled using the RT3D code to estimate whether MNA has the potential to meet the site‐specific remediation goals and the requirements of the US EPA Office of Solid Waste and Emergency Response Directive 9200.4‐17P. Modeling results were incorporated into the long‐term monitoring plan as a basis for evaluating the effectiveness of the MNA remedy. As part of the long‐term monitoring plan, monitoring data will be compared to predictive simulation results to evaluate whether the plume is changing over time as predicted and can be expected to stabilize and meet remediation goals. This deterministic approach was used to support acceptance of MNA as a remedy. © 2007 Wiley Periodicals, Inc. 相似文献
912.
913.
A better understanding of corporate strategy under regulatory uncertainty enables policy makers to improve policy making efficiency and enhance regulations’ effectiveness. Based on a review of the literature on policy formulation, we propose that regulatory uncertainty is characterized by a dependence on political negotiation, a discrete scenario structure, and a discontinuous resolution. Data from a worldwide survey show that firms pursue response strategies to regulatory uncertainty that address these characteristics by participating in policy making and increasing strategic flexibility. Surprisingly, the results also show that regulatory uncertainty only partly causes firms to postpone strategic decisions. We find that existing regulation and a need to act quickly despite regulatory uncertainty are opposed to the pursuit of a postponement strategy. We conclude that improving the mechanisms by which firms participate in early stages of the policy making process could enable them to operate in a more target-oriented manner, allow for more efficient policy implementation, and increase a regulation's effectiveness. 相似文献
914.
Johanna Christian Lee M. Frank Rob Olivier Ghislain Stphane Teresa Pinto Nadine Irina 《Environmental Science & Policy》2009,12(5):562-572
The goal oriented framework (GOF) for indicators has been developed as part of a comprehensive research project developing computerised tools for integrated assessment of the effects of new policies or technologies on agricultural systems (SEAMLESS-IF). The ambition has therefore been to create an indicator framework where the environmental, economic and social dimensions of sustainable development can be related to each other in a consistent way. Integrated assessment tools rely on such frameworks to capture and visualise trade-offs (antagonisms or synergies) among indicators between and within the three dimensions of sustainable development. The specific aims of this paper are to (i) present the GOF (ii) present how the GOF can be used to select indicators within the integrated assessment framework SEAMLESS-IF and (iii) discuss the advantages and limitations with the proposed approach. We show that the GOF has several advantages. Its major rewards are its relative simplicity and the possibility to link indicators to policy goals of each dimension of sustainability and thereby facilitate the comparison of the impacts of the new policy on the different dimensions. Another important feature of the GOF is its multi-scale perspective, which will enable the comparison of effects of a new policy between scales. Yet, as typical for all indicator frameworks, the GOF has also biases either instigated by the issues the included models cover or by the stakeholders’ selection of indicators. However, due to the way the GOF and its indicators are technically implemented in SEAMLESS-IF, it can easily be extended and include new indicators to increase and update its policy relevance. 相似文献
915.
Jan Sendzimir Zsuzsana Flachner Claudia Pahl-Wostl Christian Knieper 《Environmental Science & Policy》2010,13(7):604-619
In river basins transformation from traditions of reactive flood defense to more adaptive management regimes is difficult. How regime components reinforce each other to set its development path may induce inertia and path dependency. Transformation may require profound shifts in the institutions, technologies, and personnel as well as the ecological, economic and social processes they influence in setting the basin's trajectory. Regime change has become an issue in Hungary following repeated failures of conventional management policies to handle a series of floods on the Tisza river starting in 1997. Increasing public participation pushed water policy debate toward more experimentation with alternatives, but implementation appears stalled. In this paper we review hypotheses about what factors are bridges or barriers to transformation and then use the Management Transition Framework to examine how the interactions linking action situations, operational outcomes, knowledge and institutions influenced the river management policy debate in Hungary from 1997 to 2009. Specifically we examined which factors characteristic of conventional Control vs. progressive Adaptive management regimes influenced these interactions in ways that contributed to or hindered transformation. We found that governance and social learning issues predominated, with lesser roles played by factors related to integration of sectors and different levels in the science and policy of river management. 相似文献
916.
Factors affecting trace element content in periurban market garden subsoil in Yunnan Province, China 总被引:1,自引:0,他引:1
Field investigations were conducted to measure subsoil trace element content and factors influencing content in an intensive periurban market garden in Chenggong County,Yunnan Province,South-West China.The area was divided into three different geomorphological units:specifically,mountain (M),transition (T) and lacustrine (L).Mean trace element content in subsoil were determined for Pb (58.2 mg/kg),Cd (0.89 mg/kg),Cu (129.2 mg/kg),and Zn (97.0 mg/kg).Strong significant relationships between trace element con... 相似文献
917.
Christian Kuhlicke Annett Steinführer Chloe Begg Chiara Bianchizza Michael Bründl Matthias Buchecker Bruna De Marchi Marina Di Masso Tarditti Corina Höppner Bla? Komac Louis Lemkow Jochen Luther Simon McCarthy Luigi Pellizzoni Ortwin Renn Anna Scolobig Meera Supramaniam Sue Tapsell Gisela Wachinger Gordon Walker Rebecca Whittle Matija Zorn Hazel Faulkner 《Environmental Science & Policy》2011,14(7):804-814
Social capacity building for natural hazards is a topic increasingly gaining relevance not only for so-called developing countries but also for European welfare states which are continuously challenged by the social, economic and ecological impacts of natural hazards. Following an outline of recent governance changes with regard to natural hazards, we develop a heuristic model of social capacity building by taking into account a wide range of existing expertise from different fields of research. Particular attention is paid to social vulnerability and its assessment, as well as to risk communication and risk education as specific strategies of social capacity building. We propose to distinguish between interventionist and participatory approaches, thus enabling for a better understanding of existing practices of social capacity building as well as their particular strengths and weaknesses. By way of conclusion, we encourage more research on social capacity building for natural hazards in the European context which at present is highly diverse and, at least in parts, only poorly investigated. 相似文献
918.
Franziska Rohr Christian Ulrichs Monika Schreiner Chau Nhi Nguyen Inga Mewis 《Chemoecology》2011,21(3):171-180
Glucosinolates (GSs) are part of a two-component defence system, characteristic for the Brassicales, including the model species
Arabidopsis thaliana (L.) Heynh. The defence activity of GSs is associated with different side chain structures. The AOP genes are central in side-chain modification. AOP2 mediates formation of alkenyl GS from a methylsulfinyl precursor, whereas
AOP3 catalyzes production of hydroxy-alkyl GSs from the same precursor. Although several studies have assessed the role of
GSs in plant defence, the function of specific aliphatic GSs in plant defence is still not clarified. Structural different
GSs may influence insect herbivores differentially. We created a set of plant lines derived of a cross between two A. thaliana accessions, Gie-0 × Sap-0, which dominantly accumulate either 3-methylsulfinylpropyl GS or 3-hydroxypropyl GS. The generalist
Spodoptera exigua (Hübner) (Lepidoptera: Noctuidae) and the crucifer-specialist Pieris brassicae (L.) (Lepidoptera: Pieridae) were used as model insects, to study effects of individual aliphatic GSs on lepidopteran herbivores
with a different feeding specialization. However, the experiments revealed that weight gain of S. exigua and P. brassicae third and fourth-larval instars was similar on both chemotypes. But leaf consumption of the generalist was higher on 3-methylsulfinylpropyl-producing
lines with low GS levels (23.2 μmol g−1) than on 3-hydroxypropyl-producing lines that contained a more than twofold higher amount of GSs (60 μmol g−1). In contrast, no differential effects of non-hydroxylated and hydroxylated GSs were found on the specialist P. brassicae. Our study indicates that there is no simple relationship between GS content and insect responses. 相似文献
919.
Routti H Letcher RJ Born EW Branigan M Dietz R Evans TJ Fisk AT Peacock E Sonne C 《Journal of environmental monitoring : JEM》2011,13(8):2260-2267
Spatial trends and comparative changes in time of selected trace elements were studied in liver tissue from polar bears from ten different subpopulation locations in Alaska, Canadian Arctic and East Greenland. For nine of the trace elements (As, Cd, Cu, Hg, Mn, Pb, Rb, Se and Zn) spatial trends were investigated in 136 specimens sampled during 2005-2008 from bears from these ten subpopulations. Concentrations of Hg, Se and As were highest in the (northern and southern) Beaufort Sea area and lowest in (western and southern) Hudson Bay area and Chukchi/Bering Sea. In contrast, concentrations of Cd showed an increasing trend from east to west. Minor or no spatial trends were observed for Cu, Mn, Rb and Zn. Spatial trends were in agreement with previous studies, possibly explained by natural phenomena. To assess temporal changes of Cd, Hg, Se and Zn concentrations during the last decades, we compared our results to previously published data. These time comparisons suggested recent Hg increase in East Greenland polar bears. This may be related to Hg emissions and/or climate-induced changes in Hg cycles or changes in the polar bear food web related to global warming. Also, Hg:Se molar ratio has increased in East Greenland polar bears, which suggests there may be an increased risk for Hg(2+)-mediated toxicity. Since the underlying reasons for spatial trends or changes in time of trace elements in the Arctic are still largely unknown, future studies should focus on the role of changing climate and trace metal emissions on geographical and temporal trends of trace elements. 相似文献
920.
Nature-based solutions (NBS), understood as actions that use ecosystem processes to address societal needs, can play important roles to future-proof river landscape development for people and nature. However, knowledge gaps exist how NBS can be planned and implemented at landscape scales. This Special Issue brings together insights and experiences from studies of assessing, planning, and implementing NBS in river landscapes in Europe and beyond. It addresses three research fields: (i) NBS effects, looking at the effectiveness of NBS to achieve ecological, social, and/or economic outcomes, (ii) NBS planning, focusing on approaches for planning and designing NBS, and (iii) NBS governance, relating to governance and business models for implementation. The twelve contributions deliver evidence on how NBS outperform conventional, rather technical solutions, provide guidance and tools to operationalize the NBS concept into practice, and showcase successful governance models of NBS in different contexts. The editorial ends with an outlook on further research needs. 相似文献