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31.
Environmental Economics and Policy Studies - This paper examines convergence of per capita carbon dioxide (CO2) emission for a panel of 124 countries taking into account the impact of economic...  相似文献   
32.
Laboratory toxicity tests are a key component of the aquatic risk assessments of chemicals. Toxicity tests with Myriophyllum spicatum are conducted based on working procedures that provide detailed instructions on how to set up the experiment, e.g., which experimental design is necessary to get reproducible and thus comparable results. Approved working procedures are established by analyzing numerous toxicity tests to find a compromise between practical reasons (e.g., acceptable ranges of ambient conditions as they cannot be kept completely constant) and the ability for detecting growth alterations. However, the benefit of each step of a working procedure, e.g., the random repositioning of test beakers, cannot be exactly quantified, although this information might be useful to evaluate working procedures. In this paper, a growth model of M. spicatum was developed and used to assess the impact of temperature and light fluctuations within the standardized setup. It was analyzed how important it is to randomly reassign the location of each plant during laboratory tests to keep differences between the relative growth rates of individual plants low. Moreover, two examples are presented on how modeling can give insight into toxicity testing. Results showed that randomly repositioning of individual plants during an experiment can compensate for fluctuations of light and temperature. A method is presented on how models can be used to improve experimental designs and to quantify their benefits by predicting growth responses.  相似文献   
33.
Electrophoretic profiles of 0.1 m Tris-HCl (pH 9.0)-soluble proteins in the leaves and stems of the bilberry (Vaccinium myrtillus L.) were investigated in the latter part of the growing season (July-October), in a highly-polluted industrial area with serious forest damage (main emissions NO(2), SO(2), NH(3), urea and fertilizer dust) in Oulu, northern Finland, and in an unpolluted control forest with the same climatic and edaphic conditions. About ten protein components in the leaves and seven in the stems increased in concentration in SDS-PAGE towards the autumn, while one to four other components decreased in concentration. The pollutants in the industrial area caused a considerable decrease in the concentrations of soluble proteins, particularly in the leaves in August and September. A decrease was obtained in six components in the leaves and three components in the stems, while increases were observed in one component in the leaves (10 kDa) and four components in the stems (10, 43, 50 and 65 kDa). One reason for the lowered cold-resistance in the bilberry caused by air pollutants could thus be the lowered concentrations of certain soluble cytoplasmic proteins that protect the plant against winter conditions.  相似文献   
34.
Vertical snow sampling and moss bag transplants were used to estimate the local inorganic and organic pollutant load deposited from traffic along a major highway in Finland. The pH and concentrations of Cl(-), NO(3)(-), SO(4)(2-), Ca(2+), Na(+) and polyaromatic hydrocarbons (PAHs) were determined from snow samples collected in winter at different sites along the highway. In summer, moss bags containing 20 g of fresh red-stemmed feather moss (Pleurozium schreberi) were transplanted at the same sites. The moss bag transplants remained exposed to roadside traffic for a period of one month following which the samples were collected and the PAH profiles and concentrations were analysed. The deposition of inorganic and organic pollutants from road traffic was observed up to 60 m from the road. The prevailing winds had a significant effect on the dispersion of pollutants. Snow appears to be a good collector of inorganic pollutants from the atmosphere and can be used to monitor local airborne pollution from road traffic. Snow packs can also be used as passive collectors of organic pollutant loads from road traffic on a local scale. To monitor organic PAH deposition from the road traffic, moss bags appeared to be better indicators compared to snow sampling. The efficiency of moss bags in accumulating PAH compounds indicate that vegetation may be an important sink for traffic pollution.  相似文献   
35.
CO(2) enrichment is expected to alter leaf demand for nitrogen and phosphorus in plant species with C(3) carbon dioxide fixation pathway, thus possibly causing nutrient imbalances in the tissues and disturbance of distribution and redistribution patterns within the plants. To test the influence of CO(2) enrichment and elevated tropospheric ozone in combination with different nitrogen supply, spring wheat (Tritium aestivum L. cv. Minaret) was exposed to three levels of CO(2) (361, 523, and 639 microl litre(-1), 24 h mean from sowing to final harvest), two levels of ozone (28.4 and 51.3 nl litre(-1)) and two levels of nitrogen supply (150 and 270 kg ha(-1)) in a full-factorial design in open-top field chambers. Additional fertilization experiments (120, 210, and 330 kg N ha(-1)) were carried out at low and high CO(2) levels. Macronutrients (N, P, K, S, Ca, Mg) and three micronutrients (Mn, Fe, Zn) were analysed in samples obtained at three different developmental stages: beginning of shoot elongation, anthesis, and ripening. At each harvest, plant samples were separated into different organs (green and senescent leaves, stem sections, ears, grains). According to analyses of tissue concentrations at the beginning of shoot elongation, the plants were sufficiently equipped with nutrients. Elevated ozone levels neither affected tissue concentrations nor shoot uptake of the nutrients. CO(2) and nitrogen treatments affected nutrient uptake, distribution and redistribution in a complex manner. CO(2) enrichment increased nitrogen-use efficiency and caused a lower demand for nitrogen in green tissues which was reflected in a decrease of critical nitrogen concentrations, lower leaf nitrogen concentrations and lower nitrogen pools in the leaves. Since grain nitrogen uptake during grain filling depended completely on redistribution from vegetative pools in green tissues, grain nitrogen concentrations fell considerably with severe implications for grain quality. Ca, S, Mg and Zn in green tissues were influenced by CO(2) enrichment in a similar manner to nitrogen. Phosphorus concentrations in green tissues, on the other hand, were not, or only slightly, affected by elevated CO(2). In stems, 'dilution' of all nutrients except manganese was observed, caused by the huge accumulation of water soluble carbohydrates, mainly fructans, in these tissues under CO(2) enrichment. Whole shoot uptake was either remarkably increased (K, Mn, P, Mg), nearly unaffected (N, S, Fe, Zn) or decreased (Ca) under CO(2) enrichment. Thus, nutrient cycling in plant-soil systems is expected to be altered under CO(2) enrichment.  相似文献   
36.
Aliphatic hydrocarbons and non-polar aromatic compounds have been analyzed after a spill of grude oil at Baltic Sea 1979 from drifting weathered oil glumps, sediment and sediment trap samples and bivalves at five areas of the Finnish Archipelago Sea. Mytilus and flounder muscles and flounder livers were analyzed 1980 and 1981 from three of the previous five areas. The glumps were shown to be weathered grude oil. Sediment trap samples on the visibly contaminated area contained higher amounts of oil residues and in different ratios than the bottom sediments at the same areas. Extra local aliphatic hydrocarbon pollution was detected from the sediment traps at the reference area. Bivalves contained high amount of oil residues at visibly polluted but in some visibly non-polluted areas also 1979. Any significant decontamination was not detected at summer 1979 but next year the Mytilus samples contained only traces if any and 1981 no detectable levels of aromatic oil residues. Aliphatic hydrocarbon residues in flounders showed no regional differences and no significant change of levels between 1980 and 1981. In contrary, the aromatic oil residues decreased to the non-detectable level in flounder muscles and to a significantly lower level in flouder livers 1981 related to 1980. Linear correlations of the analysis results are discussed.  相似文献   
37.
In order to evaluate blood levels of some perfluorinated chemicals (PFCs) and compare them to current levels of classical persistent organic pollutants (POPs) whole blood samples from Sweden were analyzed with respect to 12 PFCs, 37 polychlorinated biphenyls (PCBs), p,p'-dichlorodiphenyl-dichloroethylene (DDE), hexachlorobenzene (HCB), six chlordanes and three polybrominated diphenyl ethers (PBDEs). The median concentration, on whole blood basis, of the sum of PFCs was 20-50 times higher compared to the sum of PCBs and p,p'-DDE, 300-450 times higher than HCB, sum of chlordanes and sum of PBDEs. Estimations of the total body amount of PFCs and lipophilic POPs point at similar body burdens. While levels of for example PCBs and PBDEs are normalized to the lipid content of blood, there is no such general procedure for PFCs in blood. The distributions of a number of perfluorinated compounds between whole blood and plasma were therefore studied. Plasma concentrations were higher than whole blood concentrations for four perfluoroalkylated acids with plasma/whole blood ratios between 1.1 and 1.4, whereas the ratio for perflurooctanesulfonamide (PFOSA) was considerably lower (0.2). This suggests that the comparison of levels of PFCs determined in plasma with levels determined in whole blood should be made with caution. We also conclude that Swedish residents are exposed to a large number of PFCs to the same extent as in USA, Japan, Colombia and the few other countries from which data is available today.  相似文献   
38.
Atmospheric aerosol particles were collected in a Finnish Scots pine forest as part of a European Union project. Sampling was done in March-April 2003 with a high-volume sampler. Dynamic ultrasonic-assisted solvent extraction and gas chromatography-mass spectrometry (GC-MS) were applied to the analysis of aerosol samples for analytes such as n-alkanes, polycyclic aromatic hydrocarbons (PAH), oxidized polycyclic aromatic hydrocarbons (oxy-PAHs), sesquiterpenes (SQT) and oxidized sesquiterpenes (oxy-SQT). The highest concentrations were found for the n-alkanes, which were present in a wide range (C11-C32) indicating both biogenic and anthropogenic sources. PAH compounds were found in every sample while oxy-PAH compounds were present in low concentrations in a few samples. A few oxidized monoterpenes, most notably (-)-verbenone and pinonaldehyde, were found in several samples in concentrations clearly exceeding the PAH concentrations. The effect of temperature could be seen in most samples, where the concentrations of n-alkanes declined with decreasing temperatures. Particle formation events were accompanied by higher concentrations of heavy n-alkanes, verbenone and pinonaldehyde.  相似文献   
39.
Lakes play an important role in the cycling of organic matter in the boreal landscape, due to the frequently high extent of bacterial respiration and the efficient burial of organic carbon in sediments. Based on a mass balance approach, we calculated a carbon budget for a small humic Swedish lake in the vicinity of a potential final repository for radioactive waste in Sweden, in order to assess its potential impact on the environmental fate of radionuclides associated with organic matter. We found that the lake is a net heterotrophic ecosystem, subsidized by organic carbon inputs from the catchment and from emergent macrophyte production. The largest sink of organic carbon is respiration by aquatic bacteria and subsequent emission of carbon.dioxide to the atmosphere. Although the annual burial of organic carbon in the sediment is a comparatively small sink, it results in the build-up of the largest carbon pool in the lake. Hence, lakes may simultaneously disperse and accumulate organic-associated radionuclides leaking from a final repository.  相似文献   
40.
A five-stage sequential leaching procedure was used to fractionate 13 heavy metals (Cd, Cu, Pb, Cr, Zn, Fe, Mn, Al, Ni, Co, As, V, Ba) and sulphur (S) in lime waste from the lime kiln at the causticizing plant of Stora Enso Oyj Veitsiluoto Pulp Mills at Kemi, Northern Finland, into the following fractions: (1) water-soluble fraction (H2O), (2) exchangeable fraction (CH3COOH), (3) easily reduced fraction (HONH3Cl), (4) oxidizable fraction (H2O2 + CH3COONH4), and (5) residual fraction (HF + HNO3 + HCl). Although metals were leachable in all fractions, the highest concentrations for most of the metals were observed in the residual fraction (stage 5). It was also notable that the total heavy metal concentrations in lime waste did not exceed the maximal allowable heavy metal concentrations for soil conditioner agents set by the ministry of the Agricultural and Forestry in Finland. The heavy metals concentrations in lime waste were also lower than the maximal allowable heavy metals concentrations of the European Union Directive 86/278/EEC on the protection of environment, and in particular of the soil, when sewage sludge is used in agriculture. The Ca concentration (420 g kg−1; d.w.) was about 262 times higher than the typical value of 1.6 g kg−1 (d.w.) in arable land in Central Finland. However, the concentration Mg (0.2 g kg−1; d.w.) in lime waste was equal to the Mg concentration in arable land in the Central Finland. The lime waste has strongly alkaline pH (12.8) and a neutralizing value (i.e. liming effect) of 47.9% expressed as Ca equivalents (d.w.). This indicates lime waste to be a potential soil conditioner and improvement as well as a pH buffer.  相似文献   
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