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281.
α-Hexachlorocyclohexane (HCH), β-HCH, and γ-HCH (lindane) were recently included as new persistent organic pollutants (POPs) in the Stockholm Convention. Therefore, the chemicals need to be globally addressed, including the disposal of historic wastes. At most sites, the approximately 85 % of HCH waste isomers were dumped. At a former lindane factory in Hamburg and some other factories the HCH, waste was recycled producing residues with high polychlorinated dibenzo-p-dioxin and dibenzofuran (PCDD/PCDF) levels. The soil and ground water under the former pesticide factory was/is highly contaminated with HCH (260 tons), chlorobenzenes (550 tons), and PCDD/PCDF (6 kg toxic equivalents (TEQ)). This contamination did not result from disposal operations but from spillages and leakages during the 30 years of the factory's production history. A containment wall has been constructed around the production area to prevent the dispersal of the pollutants. The ground water is managed by a pump and treat system. Over the last 15 years, approximately 10–30 tons of this pollution reservoir has been pumped and incinerated. For the contaminated production buildings, specific assessment and demolition technologies have been applied. In addition to their HCH waste isomer deposition, former lindane/HCH productions need to be assessed for possible recycling practice of HCH and related PCDD/PCDF contamination of the production area and buildings. Since such recycling activities have taken place at several factories in different countries, the experience of assessment and management of the described production area and contaminated buildings could be valuable. Such assessment could be addressed within the frame of the Stockholm Convention.  相似文献   
282.
Perfluorooctane sulfonate (PFOS) and PFOS-related substances have been listed as persistent organic pollutants in the Stockholm Convention. From August 2012, Parties to the Convention needed to address the use, storage, and disposal of PFOS—including production sites and sites where PFOS wastes have been deposited—in their national implementation plans. The paper describes the pollution in Minnesota (USA) caused by the 3M Company at one of the largest per/polyfluorinated chemical (PFC) production facilities. From early 1950s until the end of 2002, when 3M terminated PFOS and perfluorooctanoic acid (PFOA) production, PFOS, PFOA, and other PFC production wastes were disposed around the plant and in local disposal sites. Discharges from the site and releases from deposits caused widespread contamination of ground and surface waters including local drinking water wells. Fish in the river downstream were contaminated with PFOS to levels that led to fish consumption advisories. Human exposures resulted from ingesting contaminated drinking water, requiring installation of water treatment facilities and alternate water supplies. The critical evaluation of the assessments done revealed a range of gaps in particular of human exposure where relevant exposure pathways including the entire exposure via food have not been taken into consideration. Currently, the exposure assessment of vulnerable groups such as children or Hmong minorities is inadequate and needs to be improved/validated by epidemiological studies. The assessment methodology described for this site may serve—with highlighted improvements—as a model for assessment of other PFOS/PFC production sites in the Stockholm Convention implementation.  相似文献   
283.
Pape R  Löffler J 《Ambio》2012,41(5):421-434
Reindeer grazing has been entitled as ecological keystone in arctic-alpine landscapes. In addition, reindeer husbandry is tightly connected to the identity of the indigenous Sámi people in northern Europe. Nowadays, reindeer husbandry is challenged in several ways, of which pasture degradation, climate change, conflicting land uses and predation are the most important. Research on reindeer-related topics has been conducted for more than half a century and this review illuminates whether or not research is capable to match these challenges. Despite its high quality, traditional reindeer-related research is functionally isolated within the various disciplines. The meshwork of ecology, socio-economy, culture and politics, however, in which reindeer husbandry is embedded by various interactions, will remain unclear and difficult to manage, if actors and relationships are kept separate. We propose some targets for new integrative research approaches that incorporate traditional knowledge and focus on the entire human-ecological system 'reindeer husbandry' to develop solutions for its challenges.  相似文献   
284.
Focusing on a 2.2 million hectare area surrounding the Lolo National Forest in western Montana, USA, we illustrate a GIS method for predicting patterns of human use on public lands and highlighting potential for impacts on fish and wildlife species. Data inputs include human population count (derived from the 1990 Census), roads and trails, and the predicted distributions of bull trout (Salvelinus confluentus) and 41 terrestrial vertebrates of special concern. Because results highlight areas where conflicts between humans and resources may occur, they are of potential use to land managers. This approach can be applied wherever data are available, and inputs can be varied according to the topics of interest.  相似文献   
285.
A computer aided tool was created for the calculation of emission values in Saxony. It is based on the Geographic Information System ArcInfo and enables the emission values for past, present and future periods to be assessed. At present, the anthropogenic air pollutants SO2, NOx, CO, NH3, NMVOC, TSP, CO2, CH4 and N2O can be calculated by means of emission factors and statistical values. The tool is open to future expansions. The moduls represent the following emission groups: Power stations, large agricultural farms and large industrial plants as point sources, as well as transport, households, small consumer and the total emission of agriculture as area sources. The local resolution of emission values, the relationship of emission values to geographic or political territories, the inclusion of a high resolved digital street network, and the use of actual data concerning land use, density of population and density of build up areas are realized by GIS ArcInfo. The dynamic emission inventory can be used, alone or in conjunction with an atmospheric dispersion model, to assess trends in air quality.  相似文献   
286.
A study was undertaken on drained and undrained 1 ha grassland lysimeters to assess the effectiveness of multiple novel tracing techniques in understanding how agricultural slurry waste moves from land to water. Artificial fluorescent particles designed to mimic the size and density of organic slurry particles were found to move off the grassland via inter-flow (surface + lateral through-flow) and drain-flow. Where both pathways were present the drains carried the greater number of particles. The results of the natural fluorescence and δ13C of water samples were inconclusive. Natural fluorescence was higher from slurry-amended lysimeters than from zero-slurry lysimeters, however, a fluorescence decay experiment suggested that no slurry signal should be present given the time between slurry application and the onset of drainage. The δ13C values of >0.7 microm and <0.7 microm material in drainage were varied and unrelated to discharge. The mean value of >0.7 microm δ13C in water from the drain-flow pathways was higher from the lysimeter which had received naturally enriched maize slurry compared to the lysimeter which received grass slurry indicating a contribution of slurry-derived material. Values of <0.7 microm δ13C from the same pathway, however, produced counter intuitive trends and may indicate that different fractions of the slurry have different δ13C values.  相似文献   
287.
A pilot study is presented evaluating selected chlorinated pesticides as chemical tracers for water masses in a sub-Arctic fjord system (Godth?bsfjord, western Greenland). Polyoxymethylene (POM) based passive water samplers were deployed during summer-autumn 2010. The levels of the analysed chlorinated pesticides in the fjord surface waters were found to be low compared to earlier studies. α-Hexachlorocyclohexane (α-HCH) and hexachlorobenzene (HCB) were the predominant contaminants. However, these two compounds have higher levels in oceanic water compared to freshwater influenced fjord waters. These chemicals can thus be considered as indicators for direct atmospheric long-range transport, while the organochlorine pesticides like trans-, cis-chlordane, trans-nonachlor and oxychlordane that are detected in the inner parts of the fjord are indicators for potential freshwater sources such as rivers and glacial meltwater runoff (secondary sources). The average values were 50 pg L(-1) for HCB and 11 pg L(-1) for α-HCH. These concentrations are comparable to levels in fjords in Svalbard (Norwegian Arctic), but lower than in open and/or ice covered oceans in the Canadian Arctic. Two air samplers were deployed for the identification of direct atmospheric contributions. Local contamination sources do not contribute significantly. The study demonstrated the value of passive water sampling devices for comprehensive hydrological characterization of Arctic coastal waters.  相似文献   
288.
Ambio - Ecosystem service assessments rarely consider flows between distant regions. Hence, telecoupling effects such as conservation burdens in distant ecosystems are ignored. We identified...  相似文献   
289.
During injection of carbon dioxide (CO2) into deep saline aquifers, the available pore volume of the aquifer may be used inefficiently, thereby decreasing the effective capacity of the repository for CO2 storage. Storage efficiency is the fraction of the available pore space that is utilized for CO2 storage, or, in other words, it is the ratio between the volume of stored CO2 and the maximum available pore volume. In this note, we derive and present simple analytical expressions for estimating CO2 storage efficiency under the scenario of a constant-rate injection of CO2 into a confined, homogeneous, isotropic, saline aquifer. The expressions for storage efficiency are derived from models developed previously by other researchers describing the shape of the CO2-brine interface. The storage efficiency of CO2 is found to depend on three dimensionless groups, namely: (1) the residual saturation of brine after displacement by CO2; (2) the ratio of CO2 mobility to brine mobility; (3) a dimensionless group (which we call a “gravity factor”) that quantifies the importance of CO2 buoyancy relative to CO2 injection rate. In the particular case of negligible residual brine saturation and negligible buoyancy effects, the storage efficiency is approximately equal to the ratio of the CO2 viscosity to the brine viscosity. Storage efficiency decreases as the gravity factor increases, because the buoyancy of the CO2 causes it to occupy a thin layer at the top of the confined formation, while leaving the lower part of the aquifer under-utilized. Estimates of storage efficiency from our simple analytical expressions are in reasonable agreement with values calculated from simulations performed with more complicated multi-phase-flow simulation software. Therefore, we suggest that the analytical expressions presented herein could be used as a simple and rapid tool to screen the technical or economic feasibility of a proposed CO2 injection scenario.  相似文献   
290.
Alkyl nitrates (C1–C5) were measured at two sites (near urban and rural) in southeast England during the Tropospheric Organic Chemistry Experiment (TORCH). Methyl nitrate was the dominant species during both campaigns accounting for on average about one third of the total measured alkyl nitrates. High mixing ratios (>50 pptv) and variability of methyl nitrate were observed at the near urban site (TORCH1) that were not seen at the rural site (TORCH2) and which could not be explained by local photochemical production or direct emissions. The diurnal variation of methyl nitrate during TORCH1 showed a morning maximum that would be consistent with nighttime chemistry followed by transport to the surface by boundary layer dynamics. Similarly, elevated morning mixing ratios were also observed during TORCH2 although the magnitudes were much smaller. As a result, methyl nitrate could represent a tracer for nighttime chemistry seen at the ground the following day. At both campaigns, the dominant source of short chain alkyl nitrates and carbonyl precursor radicals (≤C4) were from decomposition of larger compounds. The magnitude of the source increased with decreasing carbon number consistent with increasing total precursor abundance. Non-photochemical emissions of acetaldehyde and acetone could not be accounted for by automobile exhaust emissions alone and indicated that other direct sources are likely important in this environment.  相似文献   
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