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191.
Mistra's Climate Policy Research Program, Clipore, is one of the largest research programs directed to support international climate policy development, involving research groups in Sweden, Norway, United States and India. It has been running from 2004 to 2011 with a budget of more than 100 MSEK (15?M USD). The paper briefly describes the program and its outcomes in relation to climate policy development. Discussion focuses on how the program has been able to be in the front of and include the development of emissions trading systems in Europe and the United States and how the program has been able to follow and produce inputs to the agenda of the United Nations Framework Convention on Climate Change (UNFCCC). The paper also discusses how the program has managed to present its outcomes and maintain an active dialogue with the various stakeholders. The paper emphasises options and obstacles in the communication between science and policy.  相似文献   
192.
A study of the biodegradability of nonionogenic surfactants of oxyethylenated n-butyl, isobutyl, n-pentyl and isopentyl alcohols was conducted by modified static test according to International Standard Organization method 9888. Degradation was evaluated by changes in concentrations of individual oligomers, ethylene glycols, carboxylic and dicarboxylic acids. Good biological degradability was found, with a "primary" degradability of 75-98% in 10 days. Obtained results, in agreement with our previous work, proved the dominant proportion of degradative scission in the hydrophile part of surfactant molecule. During biological degradation no significant cumulation of mono- to polyethylene glycols appeared neither that of mono- or dicarboxylic acids, and degradation of these components was not a rate-determining degradation factor.  相似文献   
193.
Foliage dust contains heavy metal that may have harmful effects on human health. The elemental contents of tree leaves and foliage dust are especially useful to assess air environmental pollution. We studied the elemental concentrations in foliage dust and leaves of Acer pseudoplatanus along an urbanization gradient in Vienna, Austria. Samples were collected from urban, suburban and rural areas. We analysed 19 elements in both kind of samples: aluminium, barium, calcium, copper, iron, potassium, magnesium, sodium, phosphor, sulphur, strontium and zinc. We found that the elemental concentrations of foliage dust were significantly higher in the urban area than in the rural area for aluminium, barium, iron, lead, phosphor and selenium. Elemental concentrations of leaves were significantly higher in urban than in rural area for manganese and strontium. Urbanization changed significantly the elemental concentrations of foliage dust and leaves and the applied method can be useful for monitoring the environmental load.  相似文献   
194.

The insecticide 14C-chlorpyrifos was found mineralized in a Tunisian soil with repeated exposure to it. From this soil, a bacterial strain was isolated that was able to grow in a minimal salt medium (MSM) supplemented with 25 mg L?1 of chlorpyrifos. It was characterized as Serratia rubidaea strain ABS 10 using morphological and biochemical analyses, as well as 16S rRNA sequencing. In a liquid culture, the S. rubidaea strain ABS 10 was able to dissipate chlorpyrifos almost entirely within 48 h of incubation. Although the S. rubidaea strain ABS 10 was able to grow in an MSM supplemented with chlorpyrifos and dissipate it in a liquid culture, it was not able to mineralize 14C-chlorpyrifos. Therefore, it can be concluded that the dissipation capability of this bacteria might be attributed to its capacity to adsorb CHL. It can also be ascribed to other reasons such as the formation of biogenic non-extractable residues. In both non-sterile and sterile soil inoculated with S. rubidaea strain ABS 10, chlorpyrifos was more rapidly dissipated than in controls with DT50 of 1.38 and 1.05 days, respectively.

  相似文献   
195.
Environmental Science and Pollution Research - Rivers are dynamic systems in complex interactions with their surrounding environments. Reliable and fast interpretation of water quality is therefore...  相似文献   
196.
Environmental Science and Pollution Research - The rapidly increasing population causes an increase in consumption amounts day by day. This leads to negative effects such as the reduction of...  相似文献   
197.
Riparian forests (RF) growing along streams, rivers and lakes comprise more than 2% of the forest area in the Nordic countries (considering a 10 m wide zone from the water body). They have special ecological functions in the landscape. They receive water and nutrients from the upslope areas, are important habitats for biodiversity, have large soil carbon stores, but may emit more greenhouse gases (GHG) than the uplands. In this article, we present a review of the environmental services related to water protection, terrestrial biodiversity, carbon storage and greenhouse gas dynamics provided by RF in the Nordic countries. We discuss the benefits and trade-offs when leaving the RF as a buffer against the impacts from upland forest management, in particular the impacts of clear cutting. Forest buffers are effective in protecting water quality and aquatic life, and have positive effects on terrestrial biodiversity, particularly when broader than 40 m, whereas the effect on the greenhouse gas exchange is unclear.  相似文献   
198.
This investigation was undertaken to elucidate whether the active metabolite of malathion, malaoxon, has any role in exerting cyto- and genotoxic effects for human choriocarcinoma (JAR) cell line which is an acceptable model for human placental cells. Gas chromatography-mass spectrometry (GC-MS) analysis were separately performed on the cell compartment and supernatant cell culture medium after subjecting the cell line to different malathion concentrations (10–400 μg/mL) and for various incubation periods (0.5 to 24 hours). GC-MS analysis showed that the sonication performed for the disruption of the cells did not cause the chemical change of malathion. The uptake of malathion by the cells was relatively fast. However, the presence of malaoxon, even in trace amounts, could not be confirmed either in samples originating from disrupted cells or in the cell culture medium. Although the hydrolysis of malaoxon occurred in the culture medium, this degradation process could not be counted as a reason for the absence of malaoxon. Since both malathion and malaoxon standard compounds could be accurately detected and distinguished by the applied liquid-liquid extraction and GC-MS methods, one can conclude that, in the case of JAR cells, the parent compound, (i.e. malathion itself) is responsible for the observed in vitro cyto- and genotoxic effects. Our results indicate that the direct toxicity of malathion contributes to the complications of pregnancy observed for environmental malathion exposure.  相似文献   
199.
An epidemiological survey was conducted in the Seine estuary and in two smaller and relatively preserved estuaries on the French Atlantic coast in order to estimate the occurrence of liver lesions in European flounder, Platichthys flesus, and also to seek putative risk factors for the recorded pathologies. Four hundred and seventy-eight fish of both sexes and of different size ranges were sampled in the three studied areas, 338 of which in the Seine estuary. All fish were examined for histopathological liver lesions, while DNA adducts and otoliths were analyzed on a subsample. Five categories of hepatic lesions were recorded with the following prevalence for the Seine estuary: 36.7 % inflammations, 8 % parasites (mainly encysted nematodes), 6.5 % foci of cellular alteration (FCA), 5.3 % foci of necrosis or regeneration (FNR), and 1.5 % tumors. Inflammation occurrence increased according to age, contrary to parasitic infestations and FCA which were more prevalent in young fish, notably those of <1 year old (group 0). Tumors were only observed in females of more than two winters. Females exhibited a higher prevalence of tumors (3.0 %) and FCA (6.5 %) than males (0 and 2.6 %, respectively). Parasitic and infectious lesions and FNR were equally distributed in males and females. The prevalence of FNR was also shown to vary according to sampling season, with significantly more occurrences of liver necrosis in the fish collected in summer than in spring. Spatial differences were observed with a higher occurrence of encysted parasites in flounders from the upper Seine estuary, while inflammations predominated in flounders living downstream. Temporal trends were also noted, with an increased prevalence of parasitic infestations, inflammations, and FCA in the 2002–2003 period in comparison to the 1996–1997 one. The three flounder populations from the Seine estuary (Normandy), Ster estuary (Brittany), and Bay of Veys (Normandy) showed different spectra of hepatic lesions. Flounders from the Bay of Veys had relatively few liver lesions as compared to flounders from the two other estuaries. Flounders from the Ster estuary exhibited the highest prevalence of parasites (37.2 %) and inflammations (51.1 %). Finally, FCA and liver tumors occurred at very similar levels in both flounder populations from the Seine and the Ster estuaries. Group 0 flounders inhabiting the upper Seine estuary were more prone to parasitic and pre-neoplastic hepatic lesions and had higher levels of liver DNA adducts than the older ones living downstream. It was postulated that group 0 European flounders may serve as valuable bioindicators for assessing the quality of estuarine waters and the health status of euryhaline fish populations.  相似文献   
200.
    

Background

This study investigated the acute effect of benzo[a]anthracene, a significant compound among polycyclic aromatic hydrocarbons, on the biodegradation of a synthetic organic substrate??a peptone/meat extract mixture??under aerobic conditions.

Methods

A laboratory-scale sequencing batch reactor was sustained at steady state at a sludge age of 10?days with substrate feeding. Inhibition tests involved running a series of batch reactors initially seeded with the biomass obtained from the parent reactor. After the biomass seeding, the reactors were started with the peptone mixture and a range of initial benzo[a]anthracene concentrations between 0.5 and 88?mg/L. Experimental profiles of oxygen uptake rates and polyhydroxyalkanoates were evaluated by calibration of a selected model.

Results

Lower doses of benzo[a]anthracene had no effect on process kinetics. The noticeable acute impact was only observed with the addition of 88?mg/L of benzo[a]anthracene, but it was limited with the storage mechanism: the amount of organic substrate diverted to polyhydroxyalkanoates was significantly reduced with a corresponding decrease in the maximum storage rate, k STO, from 2.7 down to 0.6?day?1. Similarly, the maximum growth rate from internally stored polyhydroxyalkanoates was lowered from 2.3 to 1.0?day?1.

Conclusion

Among the mechanisms for direct substrate utilization, only the hydrolysis rate was slightly reduced, but otherwise, the overall COD removal efficiency was not affected.  相似文献   
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