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161.
Incentivized debt conversion is a financing mechanism that can assist countries with a heavy debt burden to bolster their long-term domestic investment in nature conservation. The Nature Conservancy, an international conservation-based nongovernmental organization, is adapting debt conversions to support marine conservation efforts by small island developing states and coastal countries. Prioritizing debt conversion opportunities according to their potential return on investment can increase the impact and effectiveness of this finance mechanism. We developed guidance on how to do so with a decision-support approach that relies on a novel threat-based adaptation of cost-effectiveness analysis. We constructed scenarios by varying parameters of the approach, including enabling conditions, expected benefits, and threat classifications. Incorporating both abatable and unabatable threats affected priorities across planning scenarios. Similarly, differences in scenario construction resulted in unique solution sets for top priorities. We show how environmental organizations, private entities, and investment banks can adopt structured prioritization frameworks for making decisions about conservation finance investments, such as debt conversions. Our guidance can accommodate a suite of social, ecological, and economic considerations, making the approach broadly applicable to other conservation finance mechanisms or investment strategies that seek to establish a transparent process for return-on-investment decision-making.  相似文献   
162.
Sediment samples from 25 sites in 17 rivers of the Pantanal (Brazil) were analyzed with the objective of evaluating pesticide contamination in sediments. Samples were extracted with an acetone, ethylacetate, and water mixture 2:2:1 (v/v/v). The extract was purified by flash chromatography with aluminum oxide and florisil. A multiresidue gas chromatography-mass spectrometry method was applied to monitor 23 pesticides of different chemical classes (organochlorine, organophosphorus, triazines, anilides and pyrethroids) with some of their degradation products. Compounds identified in sediment samples included λ -cyhalothrin (1.0 to 5.0 μ g kg? 1), p,p′-DDT (3.6 μ g kg? 1), deltamethrin (20.0 μ g kg? 1) and permethrin (1.0 to 7.0 μ g kg? 1).  相似文献   
163.
This article presents a methodology to calculate the social cost of sustainability metrics with environmental footprint evaluation tools. Measuring the impacts of a remediation project on society is challenging because the methods by which these impacts can be measured have not been established. To perform a complete sustainability assessment of a project's life cycle, costs borne by society in terms of environmental, economic, and community impacts must be evaluated. Two knowledge gaps have been identified among the sustainability assessments currently being performed during a remediation project's life cycle: (1) lack of methodologies available to evaluate impacts on the socioeconomic aspects of remediation and (2) lack of sustainability assessments conducted during the site characterization stage. Sustainability assessments were conducted on two case studies using the methodology proposed in this article: one during the site characterization stage and the other during remedial action. The results of this study demonstrated that costs borne by society from a remediation project are significant and metric specific. This study also highlighted the benefits of conducting a sustainability assessment at the site characterization stage using environmental footprint analysis tools, cost benefit analysis, and an evaluation of costs borne by society. © 2013 Wiley Periodicals, Inc.  相似文献   
164.
The effects of soil amendments on the phytoextraction of ∑DDT (DDT + DDD + DDE) from soil ([∑DDT] ∼ 1500 ng/g) by a pumpkin variety of Cucurbita pepo ssp pepo were tested and the patterns of ∑DDT storage throughout the plant shoot were examined. The soil amendments did not increase the total amount of ∑DDT extracted into plant shoots, but new information about ∑DDT distribution in the plants was obtained. As observed previously, the ∑DDT concentration in plant leaves (mean 290 ng/g) was significantly lower than in plant stems (mean 2600 ng/g). Further analysis revealed that ∑DDT composition was consistent throughout the plant shoot and that ∑DDT concentration in leaves and stems decreased exponentially as distance from the root increased, which was previously unknown. This new information about the patterns of ∑DDT uptake and translocation within pumpkin plants highlights the need for appropriate plant sampling strategies in future POPs phytoextraction research.  相似文献   
165.
Direct mercury (Hg) speciation was assessed for soil samples with a Hg concentration ranging from 7 up to 240 mg kg−1. Hg chemical forms were identified and quantified by sequential extractions and bulk- and micro-analytical techniques exploiting synchrotron generated X-rays. In particular, microspectroscopic techniques such as μ-XRF, μ-XRD and μ-XANES were necessary to solve bulk Hg speciation, in both soil fractions <2 mm and <2 μm. The main Hg-species found in the soil samples were metacinnabar (β-HgS), cinnabar (α-HgS), corderoite (Hg3S2Cl2), and an amorphous phase containing Hg bound to chlorine and sulfur. The amount of metacinnabar and amorphous phases increased in the fraction <2 μm. No interaction among Hg-species and soil components was observed. All the observed Hg-species originated from the slow weathering of an inert Hg-containing waste material (K106, U.S. EPA) dumped in the area several years ago, which is changing into a relatively more dangerous source of pollution.  相似文献   
166.
Changes in summertime organic aerosol (OA) concentrations in the Eastern U.S. are investigated for different temperature change scenarios using the chemical transport model PMCAMx-2008. OA is simulated using the volatility basis set approach, assuming that the primary emissions are semi-volatile and that the intermediate volatile and semi-volatile organic compounds are oxidized in the gas phase, resulting in products with lower volatility. For the basic temperature change scenario where biogenic emissions are kept constant, ground-level OA decreases by −0.3% K−1 on average. Increases in the north (+0.1% K−1) and decreases in the south (−0.5% K−1) are predicted. The effect of the uncertain temperature dependence of the aging rate constant is modest, changing the OA by only 0.1% K−1 over the temperature-independent case. For the more realistic scenario in which biogenic OA precursor emissions are allowed to increase with temperature (up to 10% K−1), however, average OA increases by 4.1% K−1, with even higher increases in southern regions. These results suggest that as temperature increases, complicated changes in production, partitioning and chemical aging will take place. Nevertheless, the change in biogenic emissions and subsequent production of biogenic OA is more than an order of magnitude more important than the changes in the rates of chemical and physical atmospheric processes.  相似文献   
167.
The U.S. Environmental Protection Agency (US EPA) is placing increased emphasis on the selection and implementation of remedies that accommodate the reasonably anticipated future use of contaminated land. These remedies result in the long‐term protection of human health and the environment. Postconstruction reuse of the land can significantly benefit communities in other ways as well. The launching of the Superfund Redevelopment Initiative in 1999 and the Return to Use Initiative in 2004 reflects an evolution in the US EPA's understanding of what actions can be taken to support the reuse of Superfund sites from discovery through long‐term stewardship. Through these initiatives, the US EPA has increased its understanding of site reuse and continues to explore and implement reuse assessment, reuse planning, and other tools effective in integrating reuse considerations with response activities throughout the remedial process. © 2005 Wiley Periodicals, Inc.  相似文献   
168.
Gender, although gaining attention, remains under-researched in disaster risk reduction protocols and response and recovery efforts. This study examines women's experiences of two disasters in small towns in the United States, utilising qualitative interviews with residents of Granbury and West, Texas, during the first year of disaster recovery. Granbury was struck by an EF-4 tornado on 15 May 2013, whereas an explosion occurred at a local fertiliser facility in West on 17 April 2013. The paper explores how women's experiences of inter-gender power dynamics in decision-making, the prioritisation of childcare, and women's participation in the community affect their post-disaster recovery. Previous research highlights different forms of human response and recovery vis-à-vis ‘natural’ and technological disasters, with less attention paid to gender differences. The results point to the persistent, and similar, effect of gender stratification on women's experiences across different types of disasters in the US and the continued importance of gender-sensitive disaster policies and programmes.  相似文献   
169.
Implementing a statistically valid and practical monitoring design for large-scale stream condition monitoring and assessment programs can be difficult due to factors including the likely existence of a diversity of ecosystem types such as ephemeral streams over the sampling domain; limited resources to undertake detailed monitoring surveys and address knowledge gaps; and operational constraints on effective sampling at monitoring sites. In statistical speak, these issues translate to defining appropriate target populations and sampling units; designing appropriate spatial and temporal sample site selection methods; selection and use of appropriate indicators; and setting effect sizes with limited ecological and statistical information about the indicators of interest. We identify the statistical and operational challenges in designing large-scale stream condition surveys and discuss general approaches for addressing them. The ultimate aim in drawing attention to these challenges is to ensure operational practicality in carrying out future monitoring programs and that the resulting inferences about stream condition are statistically valid and relevant.  相似文献   
170.
Riparian condition is commonly measured as part of stream health monitoring programs as riparian vegetation provides an intricate linkage between the terrestrial and aquatic ecosystems. Field surveys of a riparian zone provide comprehensive riparian attribute data but can be considerably intensive and onerous on resources and workers. Our objective was to assess the impact of reducing the sampling effort on the variation in key riparian health indicators. Subsequently, we developed a non-parametric approach to calculate an information retained (IR) statistic for comparing several constrained systematic sampling schemes to the original survey. The IR statistic is used to select a scheme that reduces the time taken to undertake riparian surveys (and thus potentially the costs) whilst maximising the IR from the original survey. Approximate bootstrap confidence intervals were calculated to improve the inferential capability of the IR statistic. The approach is demonstrated using riparian vegetation indicators collected as part of an aquatic ecosystem health monitoring program in Queensland, Australia. Of the nine alternative sampling designs considered, the sampling design that reduced the sampling intensity per site by sixfold without significantly comprising the quality of the IR, results in halving the time taken to complete a riparian survey at a site. This approach could also be applied to reducing sampling effort involved in monitoring other ecosystem health indicators, where an intensive systematic sampling scheme was initially employed.  相似文献   
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