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481.
Despite numerous international studies on climate change, there is skepticism in the media and it is prominent in public opinion polls. This article focuses in particular on the framing of climate skepticism in Germany, a country that, in the main, is said to be convinced about climate change. By using a two-step content analysis of 379 news articles (print and online) we demonstrate that climate skepticism is present in German news media reporting on the 17th Conference of the Parties (COP17) to the United Nations Framework Convention on Climate Change in Durban, South Africa. We identify two overarching skepticism frames: skepticism about the phenomenon of climate change and about climate science. Our analysis further shows that climate skepticism is not exclusive to a specific political ideology, even though a newspaper's ideology may influence how skeptical frames are being evaluated.  相似文献   
482.
Olof Lindén  Jonas Pålsson 《Ambio》2013,42(6):685-701
The study shows extensive oil contamination of rivers, creeks, and ground waters in Ogoniland, Nigeria. The levels found in the more contaminated sites are high enough to cause severe impacts on the ecosystem and human health: extractable petroleum hydrocarbons (EPHs) (>10-C40) in surface waters up to 7420 μg L−1, drinking water wells show up to 42 200 μg L−1, and benzene up to 9000 μg L−1, more than 900 times the WHO guidelines. EPH concentrations in sediments were up to 17 900 mg kg−1. Polycyclic aromatic hydrocarbons concentrations reached 8.0 mg kg−1, in the most contaminated sites. The contamination has killed large areas of mangroves. Although the natural conditions for degradation of petroleum hydrocarbons are favorable with high temperatures and relatively high rainfall, the recovery of contaminated areas is prevented due to the chronic character of the contamination. Oil spills of varying magnitude originates from facilities and pipelines; leaks from aging, dilapidated, and abandoned infrastructure; and from spills during transport and artisanal refining of stolen oil under very primitive conditions.

Electronic supplementary material

The online version of this article (doi:10.1007/s13280-013-0412-8) contains supplementary material, which is available to authorized users.  相似文献   
483.
It is frequently assumed that males have an almost unlimited reproductive capacity, while access to receptive females is typically limiting. Consequently, sexual selection is expected to favor vigorous courtship behavior in males. If such behavior is associated with non-trivial costs, ample current mating opportunities should be accompanied by a reduction in future mating vigor. To test this hypothesis, three treatments differing in sex ratio were established using the tropical butterfly Bicyclus anynana: 50 males each were housed either with 0, 25, or 50 females. Mating trials involving the competition among males from each treatment for a single virgin female were carried out on days 3, 9, and 15 after allocation to treatments. While there was no difference on day 3, prior mating opportunity clearly reduced mating success on days 9 and 15, being lowest if identical numbers of males and females were housed together. This finding suggests accumulating costs associated with high courtship and/or mating activity. Further, older males were more active and initiated copulation earlier than the younger ones, consistent with the residual reproductive value hypothesis. We found no evidence for a survival or fertility cost of mating.  相似文献   
484.
Dawn chorusing by guereza black-and-white colobus monkeys is one of the most impressive spectacles of African rainforests. This vocal behaviour is highly contagious, travelling from one neighbouring group to the next, until a wide forest area is covered by calling monkeys. Chorusing usually occurs up to 2 h before dawn, sometimes more than once, unless the preceding night was cold and wet. We conducted a series of playback experiments, which showed that guerezas’ chorusing was difficult to elicit experimentally, suggesting that callers took several variables into account before responding to other monkeys’ predawn calls. Acoustic analyses showed that morning calls were individually distinct, but we found no evidence that callers took individual identity into account in their decision to participate in chorusing. The only way to reliably elicit chorusing in our study area was to broadcast recordings of morning choruses for longer than 30 s and at a time when a chorus simultaneously emerged in a distant part of the forest.  相似文献   
485.
The amount of nitrogen gases (N2O, NO and N2) emitted from forest soils depends on interactions between soil properties, climatic factors and soil management. To increase the understanding of nitrogen processes in soil ecosystems, two dynamic models, CoupModel (coupled heat and mass transfer model for soil–plant–atmosphere systems) and the denitrification–decomposition (DNDC) model were selected. Both are dynamic models with different submodels for soil, vegetation, hydrology and climate system. CoupModel has a higher degree of detail on soil physical and abiotic components, whereas the DNDC model contains details of microbiological processes involved in production of nitrogen gases. To improve the previous simple submodel of nitrogen emission in CoupModel, we included a submodel corresponding to the forest version of DNDC containing photosynthesis/evapotranspiration-nitrogen (PnET-N-DNDC model).  相似文献   
486.
Ambio - The Circumpolar Biodiversity Monitoring Programme (CBMP) provides an opportunity to improve our knowledge of Arctic arthropod diversity, but initial baseline studies are required to...  相似文献   
487.
Objective: The objective of this study was to quantify the population-based effects of a lower shoulder belt load limit on front row occupants in frontal car crashes.

Method: Crashes of modern vehicles from the GIDAS (German In-Depth Accident Study) are corrected for bias and projected to the national level. Injury risk functions are computed for the injury severity levels Maximum Abbreviated Injury Scale (MAIS) 2+, MAIS 3+, and fatal, stratified by 2 age cohorts (16–44 years of age and 45 years or older). To assess the field effectivity of a “softer belt,” the projected crash frequency data are modified separately for the 2 age cohorts such that its risk structure represents the risk of a softer belt. Given those 2 samples, the field effectivity of a softer belt is derived for several shares of the younger age cohort according to the injury severity levels MAIS 2+, MAIS 3+, and fatal.

Results: The injury risk distribution of the projected crash frequency data, represented here by the injury risk functions obtained, fits well into the injury risk distribution of other data sets (Sweden, United States, and Japan) given in the literature. The relative effects of a lower belt force are stable over the different ratios of the younger and old age cohorts. At the MAIS 2+ level, a lower belt force can significantly reduce the number of injuries (about 10%). A lower belt force does not significantly affect the number of MAIS 3+ injuries. A lower belt force can, however, more than double the number of fatal injuries.

Conclusions: Because the number of fatal injuries rises dramatically due to lower belt force, the reduction in the number of MAIS 2+ injuries comes at a very high cost. Therefore, whether reducing the belt force limit is the right approach is questionable.  相似文献   

488.
Haiss A  Kümmerer K 《Chemosphere》2006,62(2):294-302
Pharmaceuticals and contrast media have been detected in hospital effluents, sewage treatment plants, surface water, and ground water. Only little is known about their elimination during sewage treatment and effects of possible biotransformation products against bacteria. The modified Zahn-Wellens test (ZWT, OECD 302 B) and a test simulating biological sewage treatment (modified OECD 303 A test) were used to assess the biodegradability of the widely used ionic iodinated contrast agent diatrizoic acid (diatrizoate). Effects against sewage sludge bacteria were studied in the two test systems by monitoring the biomarkers quinones, polyamines, phospholipids and adenosine triphosphate. Diatrizoate was biotransformed into 2,4,6-triiodo-3,5-diamino-benzoic acid in the ZWT. 2,4,6-Triiodo-3,5-diamino-benzoic acid was stable under the test conditions of the ZWT. Diatrizoate was not eliminated in the OECD 303 A simulation test. It was not adsorbed by the sewage sludge. No effects of the test compound or its aerobic transformation products against the bacteria present in the sewage sludge were detected using phospholipids, quinones, polyamines, and adenosine triphosphate as biomarkers.  相似文献   
489.
志愿协议(VAs)正在作为环境政策的一种新手段出现,因为它们有超过传统政策措施的优势.具体地说,它们是经济上效率更高的.德国工业界涉及众多工业协会、大概是世界上最昂贵的1996年志愿气候保护协议,是以到2005年显著削减CO2为目标的.这项志愿协议的实施是由一个独立机构按年度监测的.从全球来说,志愿协议应当与联合实施和排放交易相互联系,从而使国际气候保护政策更加灵活和成本有效.  相似文献   
490.
The synthesis of eleven environmentally relevant mono-, di- and trichlorodibenzothiophenes (2) by photochemical ring-closure of polychlorodiphenylsulfides (1) is described. All monochlorodibenzothiophenes were additionally synthesized starting with a chlorothiophenol in a three-step reaction adapted from the synthesis of methyldibenzothiophenes.  相似文献   
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