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871.
872.
This paper illustrates a step-by-step approach for evaluating chemical monitoring data in air and deposition and for prioritizing chemicals to be included in long-term air monitoring programs. The usability of the method is shown by application to data generated within the Swedish screening program. The suggested prioritization approach uses a novel methodology by combining empirical data on occurrence in air and deposition with publicly available quantitative structure activity relationship estimation tools that predict atmospheric persistence and bioaccumulation. A selection tree is presented, which may be used by regulatory bodies to prioritize chemicals for long-term air monitoring. A final ranking list is presented proposing a prioritization order for inclusion in monitoring programs. Based on the suggested strategy, the chemicals identified as most relevant to include in Swedish long-term monitoring programs were short-chain chlorinated paraffins(C10-C13), perfluorooctane sulfonate, octachlorostyrene, hexabromocyclododecane, hexachlorobenzene, pentachloroanisole, decamethylcyclopentasiloxane, octamethylcyclotetrasiloxane, pentachlorobenzene, 1,2,3,4-tetrachlorobenzene, hexachlorobutadiene, dodecamethylcyclohexasiloxane, perfluorodecane sulfonate, 1,2,4,5-tetrachlorobenzene, and pentabromophenol.  相似文献   
873.
A correct characterization of the status and trend of forest condition is essential to support reporting processes at national and international level. An international forest condition monitoring has been implemented in Europe since 1987 under the auspices of the International Co-operative Programme on Assessment and Monitoring of Air Pollution Effects on Forests (ICP Forests). The monitoring is based on harmonized methodologies, with individual countries being responsible for its implementation. Due to inconsistencies and problems in sampling design, however, the ICP Forests network is not able to produce reliable quantitative estimates of forest condition at European and sometimes at country level. This paper proposes (1) a set of requirements for status and change assessment and (2) a harmonized sampling strategy able to provide unbiased and consistent estimators of forest condition parameters and of their changes at both country and European level. Under the assumption that a common definition of forest holds among European countries, monitoring objectives, parameters of concern and accuracy indexes are stated. On the basis of fixed-area plot sampling performed independently in each country, an unbiased and consistent estimator of forest defoliation indexes is obtained at both country and European level, together with conservative estimators of their sampling variance and power in the detection of changes. The strategy adopts a probabilistic sampling scheme based on fixed-area plots selected by means of systematic or stratified schemes. Operative guidelines for its application are provided.  相似文献   
874.
Amphipod crustaceans belong to the most successful invaders of aquatic environments. The work provides information concerning the spatial and temporal scales of expansion of four alien gammarid amphipods (three of them of Ponto-Caspian and one of North American origin): Pontogammarus robustoides (G.O. Sars, 1894), Obesogammarus crassus (G.O. Sars, 1894), Dikerogammarus haemobaphes (Eichwald, 1841), and Gammarus tigrinus Sexton, 1939 in the Vistula Lagoon (VL) and the Vistula Delta (VD) in 2008–2010. The mean abundance of these gammarids in nearshore zones was 382 ind?m?2 in VL and 89 ind?m?2 in VD. Their mean biomasses were likewise greater in VL (0.91 g?m?2) than in VD (0.49 g?m?2). G. tigrinus was the most dominant species in both nearshore zones of VL and VD and attained the highest frequency in these areas. The study gives evidence of total extinction of native gammarid species.  相似文献   
875.
876.
Mussels have the ability to control biomineral production and chemical composition, producing shells with a range of functions. In addition to biological control, the environment also seems to influence the process of biomineralization; thus, shells can be used as archives of ambient water parameters during the calcium carbonate deposition. Past and present environmental conditions are recorded in the shells in the form of various proxies including Mg/Ca or Sr/Ca ratios. For such proxies to be accurate and robust, the influence of biological effects including the size of studied organism must be examined and eliminated or minimized, so that the environmental signal can be efficiently extracted. This study considers mineralogy and elemental composition of shells representing four size classes of Mytilus trossulus from the Baltic Sea. Obtained results suggest that mineralogy and chemical composition change throughout the shell development due to most likely a combination of environmental and biological factors. The content of aragonite increases with increasing shell size, while the bulk concentrations of Na, Cd, Cu, U, V, Zn and Pb were found to decrease with increasing height of the shells. Therefore, using mussels for environmental monitoring requires analysis of individuals in the same size range.  相似文献   
877.
Grennfelt  Peringe  Engleryd  Anna  Forsius  Martin  Hov  Øystein  Rodhe  Henning  Cowling  Ellis 《Ambio》2020,49(4):849-864

Because of its serious large-scale effects on ecosystems and its transboundary nature, acid rain received for a few decades at the end of the last century wide scientific and public interest, leading to coordinated policy actions in Europe and North America. Through these actions, in particular those under the UNECE Convention on Long-range Transboundary Air Pollution, air emissions were substantially reduced, and ecosystem impacts decreased. Widespread scientific research, long-term monitoring, and integrated assessment modelling formed the basis for the policy agreements. In this paper, which is based on an international symposium organised to commemorate 50 years of successful integration of air pollution research and policy, we briefly describe the scientific findings that provided the foundation for the policy development. We also discuss important characteristics of the science–policy interactions, such as the critical loads concept and the large-scale ecosystem field studies. Finally, acid rain and air pollution are set in the context of future societal developments and needs, e.g. the UN’s Sustainable Development Goals. We also highlight the need to maintain and develop supporting scientific infrastructures.

  相似文献   
878.
Carroll, Rosemary W.H., Greg Pohll, David McGraw, Chris Garner, Anna Knust, Doug Boyle, Tim Minor, Scott Bassett, and Karl Pohlmann, 2010. Mason Valley Groundwater Model: Linking Surface Water and Groundwater in the Walker River Basin, Nevada. Journal of the American Water Resources Association (JAWRA) 46(3):554-573. DOI: 10.1111/j.1752-1688.2010.00434.x Abstract: An integrated surface water and groundwater model of Mason Valley, Nevada is constructed to replicate the movement of water throughout the different components of the demand side of water resources in the Walker River system. The Mason Valley groundwater surface water model (MVGSM) couples the river/drain network with agricultural demand areas and the groundwater system using MODFLOW, MODFLOW’s streamflow routing package, as well as a surface water linking algorithm developed for the project. The MVGSM is capable of simulating complex feedback mechanisms between the groundwater and surface water system that is not dependent on linearity among the related variables. The spatial scale captures important hydrologic components while the monthly stress periods allow for seasonal evaluation. A simulation spanning an 11-year record shows the methodology is robust under diverse climatic conditions. The basin-wide modeling approach predicts a river system generally gaining during the summer irrigation period but losing during winter months and extended periods of drought. River losses to the groundwater system approach 25% of the river’s annual budget. Reducing diversions to hydrologic response units will increase river flows exiting the model domain, but also has the potential to increase losses from the river to groundwater storage.  相似文献   
879.
The authors conducted a survey based on conjoint choice experiments in Milan, Italy, about mortality risk reductions delivered by hypothetical private behaviors and public programs, and used it to estimate the value of a prevented fatality (VPF) when the cause of death is cancer. Their estimate of the VPF is 4.2 million Euros. The VPF is about C1 million larger when the risk reduction is delivered by a public program, but further analyses reveal that it is so only when the respondent believes that public programs are effective at reducing this particular type of mortality risk This estimate of the VPF is higher than generic European Union-wide figures recommended by the European Commission Directorate-General for Environment (DG Environment) for environmental policy analyses, and is comparable to other VPFs that are appropriate for Italy, hazardous waste regulations, and enforcement-based cleanup programs. The authors use their VPF to compute the benefits of addressing leaking landfills, illegal disposal of hazardous wastes, and poor hazardous waste management practices in the provinces of Naples and Caserta in southern Italy. The authors also examine the importance of the discount rates, since the mortality benefits of remediation begin in 20 yr and are assumed to continue over 30 yr.  相似文献   
880.

Introduction  

Naturally occurring hydroxylated polybrominated diphenyl ethers (OH-PBDEs), their methoxylated counterparts (MeO-PBDEs), and polybrominated dibenzo-p-dioxins (PBDDs), together with their potential precursors polybrominated phenols (PBPs) and polybrominated anisoles (PBAs), were analyzed in blue mussels (Mytilus edulis) gathered along the east coast (bordering the Baltic Sea) and west coast of Sweden (bordering the North Sea). Brown algae (Dictyosiphon foenicolaceus) and cyanobacteria (Nodularia spumigena) from the Baltic Sea, considered to be among the primary producers of these compounds, were also analyzed for comparison.  相似文献   
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