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51.
In 2012, the four countries hosting the Svalbard population of pink-footed goose Anser brachyrhynchus along its flyway launched an International Species Management Plan for the population. One of the aims was to reduce conflicts between geese and agriculture to an acceptable level. Since 2006, Norway has offered subsidies to farmers that provide refuge areas for geese on their land. We evaluate the mid-Norwegian goose management subsidy scheme, with a view to its adjustment to prevailing ecological and socio-economic parameters. The analysis indicates that the legitimacy of the scheme is highly dependent on transparency of knowledge management and accountability of management scheme to the farming community. Among farmers, as well as front-line officials, outcomes of prioritisation processes within the scheme are judged unfair when there is an evident mismatch between payments and genuine damage. We suggest how the scheme can be made more fair and responsive to ecological changes, within a framework of adaptive management.  相似文献   
52.
Environmental Science and Pollution Research - The utilisation of waste wood from furniture production brings new problems connected with an incomplete thermochemical decomposition of additives...  相似文献   
53.
Environmental Science and Pollution Research - Little is known about biosecurity measures and toxic effects during pesticide application in the province of Jujuy, Argentina, particularly concerning...  相似文献   
54.
Ambient air measurements of N2O, NOx, CO, and HC based on grab sampling were conducted in a major traffic tunnel in Sweden, that carries up to 4,000 vehicles per hour, in order to estimate real-world emissions of N2O for road traffic. Two different methods--relative and mass balance-were used to calculate a N2O emission factor for the mixed vehicle fleet, which gave an average emission factor, at average speeds of 30-70 km/h, of approximately 25 mg N2O/ km, with a range of 7-56 mg/km.  相似文献   
55.

Introduction  

High concentrations of hexabromocyclododecane (HBCD) sometimes recorded in free-range hens' eggs are thought to be due to soil ingestion. Of the three stereoisomers of HBCD (α-, β-, and γ-HBCD), γ-HBCD is the main component in the commercial mixture, as well as in environmental matrices, whereas the isomer profile is α-dominated in biota. In fish and in mammals, this shift is thought to be due to a rapid elimination of γ-HBCD and to its bioisomerization to the more persistent α-HBCD. The aim of the current controlled study was to better understand the fate of ingested HBCD in laying hens. The isomer profile in soil being γ-dominated, excretion kinetics of γ-HBCD into egg yolk, and accumulation in liver and in abdominal fat were investigated.  相似文献   
56.
The classic Microtox® solid phase assay (MSPA) based on the inhibition of light production of the marine bacteria recently renamed Aliivibrio fischeri suffers from various bias and interferences, mainly due to physico-chemical characteristics of the tested solid phase. To precisely assess ecotoxicity of sediments, we have developed an alternative method, named Microtox® leachate phase assay (MLPA), in order to measure the action of dissolved pollutants in the aqueous phase. Two hypotheses were formulated to explain the observed difference between MSPA and MLPA results: a real ecotoxicity of the solid phase or the fixation of bacteria to fine particles and/or organic matter. To estimate the latter, flow cytometry analyses were performed with two fluorochromes (known for their ability to stain bacterial DNA), allowing correction of MSPA measurements and generation of new (corrected) IC50. Comparison of results of MLPA with the new IC50 MSPA allows differentiating real ecotoxic and fixation effect in classic MSPA especially for samples with high amount of fines and/or organic matter.  相似文献   
57.
Three beehive matrices, sampled in six different apiaries from West France, were analyzed for the presence of four polycyclic aromatic hydrocarbons (PAH4: benzo[a]pyrene, benzo[a]anthracene, benzo[b]fluoranthene and chrysene). Samples were collected during four different periods in both 2008 and 2009. Honey samples showed the lowest levels of PAH4 contamination (min = 0.03 μg kg−1; max = 5.80 μg kg−1; mean = 0.82 μg kg−1; Sd = 1.17). Bee samples exhibited higher levels of PAH4 contamination (min = 0.32 μg kg−1; max = 73.83 μg kg−1; mean = 7.03 μg kg−1; Sd = 17.83) with a great dispersion of the concentrations due to four main events of high concentrations. Pollen samples showed only one major episode with the highest PAH4 concentration found (min = 0.33 μg kg−1; max = 129.41 μg kg−1; mean = 7.10 μg kg−1; Sd = 22.28). The PAH4 concentrations found were significantly influenced by the landscape context for all beehive samples.  相似文献   
58.
Temporal variations in concentrations of perfluorinated carboxylic acids (PFCAs) and sulfonic acids (PFSAs), including perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) structural isomers, were examined in livers of pilot whale (Globicephala melas), ringed seal (Phoca hisida), minke whale (Balaenoptera acutorostrata), harbor porpoise (Phocoena phocoena), hooded seal (Cystophora cristata), Atlantic white-sided dolphin (Lagenorhynchus acutus) and in muscle tissue of fin whales (Balaenoptera physalus). The sampling spanned over 20 years (1984-2009) and covered a large geographical area of the North Atlantic and West Greenland. Liver and muscle samples were homogenized, extracted with acetonitrile, cleaned up using hexane and solid phase extraction (SPE), and analyzed by liquid chromatography with negative electrospray tandem mass spectrometry (LC-MS/MS). In general, the levels of the long-chained PFCAs (C9-C12) increased whereas the levels of PFOS remained steady over the studied period. The PFOS isomer pattern in pilot whale liver was relatively constant over the sampling years. However, in ringed seals there seemed to be a decrease in linear PFOS (L-PFOS) with time, going from 91% in 1984 to 83% in 2006.  相似文献   
59.
We surveyed four different river systems in the Greater Montreal region, upstream and downstream of entry points of contamination, from April 2007 to January 2009. The studied compounds belong to three different groups: PPCPs (caffeine, carbamazepine, naproxen, gemfibrozil, and trimethoprim), hormones (progesterone, estrone, and estradiol), and triazine herbicides and their metabolites (atrazine, deethylatrazine, deisopropylatrazine, simazine, and cyanazine). In the system A, B, and C having low flow rate and high TOC, we observed the highest detection frequencies and mass flows of PPCPs compared to the other compounds, reflecting discharge of urban contaminations through WWTPs and CSOs. However, in River D, having high flow rate and low TOC, comparable frequency of detection of triazine and their by-products and PPCPs, reflecting cumulative loads of these compounds from the Great Lakes as well as persistency against natural attenuation processes. Considering large differences in the removal efficiencies of caffeine and carbamazepine, a high ratio of caffeine/carbamazepine might be an indicative of a greater proportion of raw sewage versus treated wastewater in surface waters. In addition, caffeine appeared to be a promising indicator of recent urban fecal contaminations, as shown by the significant correlation with FC (R2 = 0.45), while carbamazepine is a good indicator of cumulative persistence compounds.  相似文献   
60.
The emission of volatile pollutants from the volcanic eruption of the Puyehue-Cordón Caulle complex (North Patagonia Andean Range) that started in June 4th, 2011, was investigated by bioindication means with the epyphytic fruticose lichen Usnea sp. The elemental composition of pooled samples made up with 10 lichen thalli were analysed by Instrumental Neutron Activation Analysis. Eleven sampling sites were selected within the impacted region at different distance from the volcanic source. Five sites were selected as they were already sampled in a previous study prior to the eruption. Two other new sampling sites were selected from outside the impacted zone to provide non-impacted baseline sites.The elements associated with the lichen incorporation of particulate matter (PM) of geological origin were identified by linear correlation with a geochemical tracer (Sm concentrations). The elements associated with PM uptake were Ce, Eu, Fe, Hf, La, Lu, Na, Nd, Sb, Sc, Se, Ta, Tb, Th, U, and Yb. Arsenic and Cs concentrations showed contributions exceeding the PM fraction in sites near the volcanic centre, also higher than the baseline concentrations, which could be associated with permanent emissions from the geothermal system of the Puyehue-Cordón Caulle complex. The lichen concentrations of Ba, Ca, Co, Hg, K, Rb, Sr, and Zn were not associated with the PM, not showing higher concentrations in the sites nearby the volcanic source or respect to the baseline values either. Therefore, there is no indication of the emission of volatile forms of these elements in the lichen records. The lichen records only identified Br volatile emissions associated with the Puyehue-Cordón Caulle complex eruption in 2011.  相似文献   
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