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Danish rivers carry >50% of the phosphorus (P) transport as particulate P (PP). In five of six rivers sampled in November 1998 iron-bound P made up > 59% of PP and loosely adsorbed P ranged between 2% and 13%. This fraction could potentially be released in 14‰ seawater. The behaviour of dissolved and particulate P fractions was studied during seven month in a 2 km long estuary with low freshwater retention time and low tidal range. The river carried ∼10% of PP as loosely adsorbed P but increased concentrations of dissolved inorganic P (DIP) relative to the estuarine mixing line was only observed in the summer month with low freshwater flow and was more likely due to DIP release from the bottom sediment. Instead estuarine particles were always enriched with oxidized iron (ox.Fe) and iron-bound P as well as loosely adsorbed P and during May–September this coincided with increasing concentration of PP in estuary. We suggest that flocculation of ox.Fe and adsorption of DIP onto the particles with subsequent transport seawards is a major loss process for P during the summer month. During winter month where 85% of the run-off occurs the dominant process in the estuary is sedimentation of larger particles, however, a comparison of river particles with surface sediment clearly reveals that most PP is mobilized again from the bottom sediments.  相似文献   
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This paper draws on climate justice principles developed in the context of international negotiations between national governments to assess the distribution of carbon reduction roles between different actors involved in residential energy use within the UK. In so doing, it aims to provide a new understanding of equity aspects of current residential policy and to highlight opportunities for more effective and equitable policy. The paper uses three criteria: rights and corresponding duties; mitigation responsibilities and capabilities. It applies them systematically to assess the roles of five key actors involved in residential energy use in the UK. The assessment finds a suboptimal distribution of actors’ duties, responsibilities and capabilities and roles and discusses whether and how a more effective and fair allocation of outcomes, in terms of carbon reduction and fuel poverty, could be achieved. In particular, it raises questions about whether the right actors are being legally obliged or incentivised to deliver energy efficiency improvements, and suggests that particular actors – local authorities and community groups – are under-used and require greater government support with capability. The paper represents the first use of international climate justice frameworks to investigate residential energy policy within a country.  相似文献   
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Aryl methyl sulphones of polychlorinated biphenyls (PCBs) and 3-p,p'-DDE (MeSO(2)-PCBs and 3-MeSO(2)-p,p'-DDE), PCBs and Sigma DDTs were analysed in five different tissues (blubber, nuchal fat, liver, muscle, brain) of adult male harbour porpoises from the west coast of Sweden. Two different methods for MeSO(2)-PCBs and 3-MeSO(2)-p,p'-DDE determination were used, gas chromatography-mass spectrometry and gas chromatography-atomic emission detection. Highest concentrations of Sigma MeSO(2)-PCBs were found in liver (0.15-0.49 microg/g lipid wt.), which corresponded to 2.0-2.8% of the Sigma PCBs concentrations. Blubber and nuchal fat showed Sigma MeSO(2)-PCB concentrations that were three to five times lower than those in liver. Concentrations of 3-MeSO(2)-p,p'-DDE in liver, muscle and brain corresponded to 0.26-4.6% of the p,p'-DDE concentrations, while in blubber and nuchal fat, 3-MeSO(2)-p,p'-DDE constituted 0.033-0.21% of p,p'-DDE. The different tissues analysed showed similar levels (lipid wt.) of Sigma PCBs and Sigma DDTs, except for brain that had almost 10 times lower levels compared to the other tissues. Using the Sigma PCBs/Sigma MeSO(2)-PCBs ratio to estimate MeSO(2)-PCB formation and secondary metabolism capacity, the harbour porpoise showed a relatively low capacity of MeSO(2)-PCB formation compared to other small toothed whales and seals. Blubber sampled from five different anatomical locations showed that concentrations of contaminants may be unevenly distributed in blubber in certain animals. This should be taken into account when choosing sampling sites on the porpoise.  相似文献   
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The embryotoxicity of an artificial mixture of 18 polycyclic aromatic hydrocarbons (PAHs) was tested by injection into the yolk sacs of eggs of four avian species: chicken Gallus domesticus, turkey Meleagris gallopavo, domestic duck Anas platyrhynchos and common eider Somateria mollissima. A dose of 2.0 mg kg egg(-1) of the PAH mixture increased the mortality among the embryos of all four species. In the domestic duck, but not in the three other species, there was a significantly increased embryonic mortality at a dose of 0.2 mg kg(-1) of this mixture. All 18 individual compounds in the mixture were tested for embryotoxicity in the chicken. The compound most toxic to chick embryos was benzo[k]fluoranthene. This substance also proved to be highly embryotoxic in the three other species. Previous studies have shown coplanar polychlorinated biphenyls (PCBs) to be much more embryotoxic in the chicken than in other avian species studied. In accordance with this, eider duck embryos proved to be considerably less sensitive to 3,3',4,4'-tetrachlorobiphenyl and 3,3',4,4',5-pentachlorobiphenyl than was previously found for chick embryos. For PAHs, however, chick embryos did not have a higher sensitivity than the other species tested.  相似文献   
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瑞典约有55%的土地面积被森林所覆盖.目前,瑞典的森林覆盖没有统一的和地理学上明晰的描述.现存的独立性数据源是Landsat TM和SPOT HRV卫星数据、地图蒙片(map mask)和森林清查样地.它们在一起,使森林变量(如材枳和林分年龄)的计算机估计成为可能.这些估计的精确度在像素水平上是低的,但在林分水平上较高.在规划木材资源应如何加以利用或出于监测目的时,这类基于栅格的森林数据对政府来说是有帮助的.本文描述了以有效成本建立森林变量估计全国数据库的生成流程.我们在林分水平上评价了瑞典西南部某地森林变量估计的精确度.结果表明,总材积估计的整体均方根误差为33%,年龄估计的整体均方根误差为23%.  相似文献   
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Contents of Cd and Zn in the blue mussel, Mytilus edulis, collected on the coast of the southern Bothnian Sea and the northern Baltic proper, were determined using flame AAS. The observed concentrations ranged from 4.7 to 10.8 mg kg(-1) dw for Cd and from 121 to 215 mg kg(-1) dw for Zn. The Zn/Cd ratio was around 20 at a majority of the investigated locations. Cd exhibited an approximate two-fold gradual increase from south to north in the study area. It is likely that this increase was due largely to enhanced bioavailability for Cd at lower salinity. However, it is not possible to eliminate the influence from a generally elevated overall concentration of cadmium in the southern Bothnian Sea caused by natural and anthropogenic input. Compared to mussels from marine waters on the west coast of Sweden, Cd concentrations were 5-10 times higher, similarity indicating an influence of low salinity. Zn did not show these salinity correlated differences. The high Zn content found south of the outlet of the river Dal?lven and gradually decreasing southwards was possibly caused by the high riverine input.  相似文献   
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A flux estimate of PCDDs and PCDFs through a waste water treatment plant has been made on an annual basis. The samples were collected from different steps in the treatment procedure within the plant i.e. inlet and outlet water, different sludge types and air samples. From the surroundings of the plant were collected samples of urban air, storm sewer water (urban runoff), plant discharge water and settling particulates from a sediment trap downstream the plant discharge. Differences in congener profiles were found between the samples taken within the plant compared to those collected outside. The flux of PCDD and PCDF equivalents through the plant was found to be approximately 0.4 – 0.5 g/year and the major part was taken away as digested sludge.  相似文献   
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