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61.
Within the forest sector, the sustainability concept has evolved from a narrow focus on sustainable wood production to a much broader evaluation of environmental, social, and economic sustainability for whole value chains. A new software tool - ToSIA - has been developed for assessing sustainability impacts of Forest-Wood-Chains (FWCs). In the approach, FWCs are defined as chains of production processes (e.g. harvesting-transport-industrial processing), which are linked with products (e.g. a timber frame house). Sustainability is determined by analysing environmental, economic, and social sustainability indicators for all the production processes along the FWC. The tool calculates sustainability values as products of the relative indicator values (i.e. indicator value expressed per unit of material flow) multiplied with the material flow entering the process. Calculated sustainability values are then aggregated for the segments of the FWC or for the complete chain. The sustainability impact assessment requires carefully specified system boundaries. ToSIA uses a data-oriented approach that is very flexible in the focus of the analysis and the selection of indicators of sustainability. An example of alternative Norway spruce management systems in Southern Germany and their effects on six sustainability indicators is presented. The less intensive management system with natural regeneration and motor-manual harvesting shows higher carbon storage and slightly less energy use. It creates more employment and higher labour costs, but the average rate of accidents is also higher. ToSIA offers a transparent and consistent methodological framework to assess sustainability impacts in the forest-based sector as affected, e.g. by changes in policies, market conditions, or technology. The paper discusses strengths and limitations of the approach and provides an outlook on further development perspectives of the methodology.  相似文献   
62.
Regional Environmental Change -  相似文献   
63.
This study investigates the strategic antecedents of operational agility in humanitarian logistics. It began by identifying the particular actions to be taken at the strategic level of a humanitarian organisation to support field‐level agility. Next, quantitative data (n=59) were collected on four strategic‐level capabilities (being purposeful, action‐focused, collaborative, and learning‐oriented) and on operational agility (field responsiveness and flexibility). Using a quantitative analysis, the study tested the relationship between organisational capacity building and operational agility and found that the four strategic‐level capabilities are fundamental building blocks of agility. Collectively they account for 52 per cent of the ability of humanitarian logisticians to deal with ongoing changes and disruptions in the field. This study emphasises the need for researchers and practitioners to embrace a broader perspective of agility in humanitarian logistics. In addition, it highlights the inherently strategic nature of agility, the development of which involves focusing simultaneously on multiple drivers.  相似文献   
64.
The aim of this work was to determine the concentrations and isotopic compositions of plutonium and uranium in environmental samples for safeguards purposes. An analytical method was developed with a plutonium and uranium separation procedure based on extraction chromatography (using 2 mL TEVA and UTEVA columns) and detection with a quadrupole ICP-MS applying an ultra-sonic nebulizer coupled with a membrane desolvation system. Starting from blank swipes, the background equivalent concentration (BEC) was 8 fg for 239Pu and 1 ng 238U. The method was successfully applied to certified reference materials as well as to round robin samples obtained in the framework of the inter-laboratory exercise program, promoted by the Brazilian–Argentine Agency for Accounting and Control of Nuclear Materials (ABACC), together with the US Department of Energy (USDOE). After the introduction of an additional ion-exchange separation step, the methodology was applied to the IAEA-384 sediment reference sample with precise and accurate total plutonium and uranium, 240Pu/239Pu, 241Pu/239Pu, 234U/238U and 235U/238U atomic ratio results.  相似文献   
65.
The development of Watershed Management Plans (WMPs) in urban areas aids municipalities in allocating resources, engaging the public and stakeholders, addressing water quality regulations, and mitigating issues related to stormwater runoff and flooding. In this study, 124 urban WMPs across the United States were reviewed to characterize historic approaches and identify emerging trends in watershed planning. Planning methods and tools were qualitatively evaluated, followed by statistical analyses of a subset of 63 WMPs to identify relationships between planning factors. Plans developed by a municipality or consultant were associated with more occurrences of hydrologic modeling and site‐specific recommendations, and fewer occurrences of characterizing social watershed factors, than plans authored by agencies, organizations, or universities. WMPs in the past decade exhibited greater frequency in the use of pollutant load models and spatially explicit hydrologic and hydraulic models. Project prioritization was found to increasingly focus on feasibility to implement proposed strategies. More recent plans additionally exhibited greater consideration for water quality, ecological health, and public participation. Innovation in planning methods and consideration of future watershed conditions are primary areas that were found to be deficient in the study WMPs, although analysis methods and tools continue to improve in the wake of advancing technology and data availability.  相似文献   
66.
Increasing amounts of animal and municipal wastes are being composted before land application to improve handling and spreading characteristics, and to reduce odor and disease incidence. Repeated applications of composted biosolids and manure to cropland may increase the risk for P enrichment of agricultural runoff. We conducted field research in 2003 and 2004 on a Fauquier silty clay loam (Ultic Hapludalfs) to compare the effects of annual (since 1999) applications of composted and uncomposted organic residuals on P runoff characteristics. Biosolids compost (BSC), poultry litter-yard waste compost (PLC), and uncomposted poultry litter (PL) were applied based on estimated plant-available N. A commercial fertilizer treatment (CF) and an unamended control treatment (CTL) were also included. Corn (Zea mays L.) and a cereal rye (Secale cereal L.) cover crop were planted each year. We applied simulated rainfall in fall 2004 and analyzed runoff for dissolved reactive P (DRP), total dissolved P (TDP), total P (TP), total organic C (TOC), and total suspended solids (TSS). End of season soil samples were analyzed for Mehlich-3 P (M3P), EPA 3050 P (3050P), water soluble P (WSP), degree of P saturation (DPS), soil C, and bulk density. Compost treatments significantly increased soil C, decreased bulk density, and increased M3P, 3050P, WSP, and DPS. The concentration of DRP, TDP, and TP in runoff was highest in compost treatments, but the mass of DRP and TDP was not different among treatments because infiltration was higher and runoff lower in compost-amended soil. Improved soil physical properties associated with poultry litter-yard waste compost application decreased loss of TP and TSS.  相似文献   
67.
We examine bottom-line mentality (BLM) at the group level and examine the effect of group BLM on group psychological safety and subsequent group creativity. We draw on goal shielding theory to suggest that groups high in BLM narrowly focus on bottom-line outcomes, which encourages them to eliminate distracting considerations from their work processes. Because the group's high BLM encapsulates goal shielding, these groups are deficient in fostering psychological safety as an important interpersonal process that facilitates group creativity. We also couple goal shielding theory with arguments related to situational strength to examine group BLM agreement (i.e., the standard deviation of the mean of group BLM) as a first stage moderator. We contend that high-BLM agreement (vs. low agreement) strengthens the goal shielding effect of group BLM, which is reflected by a stronger detrimental effect on group psychological safety that then reduces group creativity. We found support for our theoretical model using multisource, multiwave field data from a diverse sample of workgroups and their supervisors. We discuss the theoretical implications of our research and provide practical suggestions for limiting the deleterious consequences of group BLMs in the workplace.  相似文献   
68.
Abstract

A saponification extraction method with gas chromatography pseudo-MRM (pMRM) mass spectrometry detection was developed for the determination of 50 total polycyclic aromatic hydrocarbons (TPAH50, a combination of parent and alkylated homologues) in biota. The method was aimed at monitoring and identification of potential TPAH contaminants in bitumen impacted environments. Alkylated PAHs were determined by multi-level, quantitative calibration using parent PAHs. The developed and thoroughly validated method required only one injection for TPAH50 analysis which represents significant saving of time and expensive authentic alkylated standards. The current method was tested with certified reference mussel tissue NIST 1974c and performed well. In a comparison study, the method reached a limit of quantitation (LOQ) for the TPAH50 between 0.1 and 0.2?ng g?1, while the QuEChERs enhanced matrix removal – lipid (EMR) kit produced by Agilent showed an LOQ of 5–10?ng g?1. The current method relied on response factors (RF) for the quantitation of alkylated PAHs determined against parent PAHs. These RFs were shown to be stable and consistent over the course of 1 year, during which over 200 routine environmental biota monitoring samples were analyzed. The environmental biota monitoring samples analyzed include muscle, carcass and liver, with an average total PAH50 concentration of 13, 90 and 135?ng g?1, respectively. Results show significant differences in the distributions of 1 ringed, 2 ringed, 3 ringed, 4 ringed, and 5+ ringed TPAHs between the types of biota samples.  相似文献   
69.
The variability of mercury (Hg) levels in Swedish freshwater fish during almost 50 years was assessed based on a compilation of 44 927 observations from 2881 waters. To obtain comparable values, individual Hg concentrations of fish from any species and of any size were normalized to correspond to a standard 1-kg pike [median: 0.69 mg kg?1 wet weight (ww), mean ± SD: 0.84 ± 0.67 mg kg?1 ww]. The EU Environmental Quality Standard of 0.02 mg kg?1 was exceeded in all waters, while the guideline set by FAO/WHO for Hg levels in fish used for human consumption (0.5–1.0 mg kg?1) was exceeded in 52.5 % of Swedish waters after 2000. Different trend analysis approaches indicated an overall long-term decline of at least 20 % during 1965–2012 but trends did not follow any consistent regional pattern. During the latest decade (2003–2012), however, a spatial gradient has emerged with decreasing trends predominating in southwestern Sweden.  相似文献   
70.
Thyroid hormones, which influence body metabolism and development, could be affected by persistent organic pollutants. We sought to examine the relationship between polybrominated biphenyls (PBBs) and polychlorinated biphenyls (PCBs) and thyroid disease. We employed incidence density sampling to perform a nested case control analysis of the Michigan Long-Term PBB Cohort. Cohort members (n = 3333) were exposed to PBBs through contaminated cattle feed in 1973-1974 and to PCBs through daily life. Those with detectable serum PBB and PCB concentrations at enrollment were categorized into tertiles of PBB and PCB exposure. Case-patients were cohort members answering “Yes” to “Has a healthcare provider ever told you that you had a thyroid problem?” during follow-up interviews; control-patients were cohort members answering “No”. We used odds ratios (OR) with 95% confidence intervals (CI) to compare odds of thyroid disease by PBB and PCB exposure and by various risk factors. Total cumulative thyroid disease incidence after 33 years was 13.9% among women and 2.6% among men. After adjusting for body mass index, we found no statistically significant differences in odds of any type of thyroid disease among women or men with elevated PBB or PCB exposure. Compared to control-patients, women with thyroid disease had increased odds of being overweight/obese (OR = 2.82, 95% CI: 1.94-4.11) and developing infertility (OR = 1.71, 95% CI: 1.08-2.69), diabetes (OR = 1.61, 95% CI: 1.04-2.51), or arthritis (OR = 1.71, 95% CI: 1.18-2.50) during follow-up. Additional research should explore potential associations between PBBs/PCBs and thyroid disease among children exposed in utero.  相似文献   
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