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91.
Unilateral climate policy can be detrimental to global climate protection. Our objective is to provide insight into such a policy, to quantify the risk of carbon leakage, and to investigate the effects related to potential anti-leakage measures. We analyze existing definitions of carbon leakage and propose an alternative, rigorous one, which is different in three respects. The definition is then tested using computable general equilibrium analysis of the global economy and decomposition analysis. We identify a list of parameters that affect not only the magnitude but also the sign of the carbon leakage rate. Manipulating elasticities of substitution suggests that carbon leakage can be either positive or negative. Computable general equilibrium models, which are widely applied, including by the European Commission in this area, should be transparent, and their assumptions call for careful validation. We find that emission limits are properly distributed between sectors covered by the European Union Emissions Trading System and other sectors for the first commitment period (ended in 2012) but not for the second one (ending in 2020), where the target for the non-trading sectors should be reduced relative to the target for the trading sectors in order to equlize marginal abatement costs.  相似文献   
92.
ABSTRACT: Timber harvest best management practices (BMPs) in Washington State were evaluated to determine their effectiveness at achieving water quality standards pertaining to sediment related effects. A weight‐of‐evidence approach was used to determine BMP effectiveness based on assessment of erosion with sediment delivery to streams, physical disturbance of stream channels, and aquatic habitat conditions during the first two years following harvest. Stream buffers were effective at preventing chronic sediment delivery to streams and physical disturbance of stream channels. Practices for ground‐based harvest and cable yarding in the vicinity of small streams without buffers were ineffective or only partially effective at preventing water quality impacts. The primary operational factors influencing BMP effectiveness were: the proximity of ground disturbing activities to streams; presence or absence of designated stream buffers; the use of special timber falling and yarding practices intended to minimize physical disturbance of stream channels; and timing of harvest to occur during snow cover or frozen ground conditions. Important site factors included the density of small streams at harvest sites and the steepness of inner stream valley slopes. Recommendations are given for practices that provide a high confidence of achieving water quality standards by preventing chronic sediment delivery and avoiding direct stream channel disturbance.  相似文献   
93.
94.
The doubly uniparental inheritance system allows for the use of two independent mitochondrial genomes for population history investigations. Under this system, two lineages of mitochondrial DNA (mtDNA) exist and males are typically heteroplasmic, having the additional, usually divergent, mitochondrial genome inherited from their male parent. This additional mtDNA typically evolves faster, potentially allowing for insight into more recent events in population history. Few studies did explore this possibility in marine mussels Mytilus showing its usefulness. Recent observations of the Mytilus trossulus mussels who have retained their native mtDNA in European waters posed the question of their origin. Are they part of a population present, but previously undetected, or is this a potentially human mediated, ongoing spread of an invasive species? To tackle this question, we amplified with species-specific primers and sequenced an approximately 1,200-bp-long fragment spanning COIII and ND2 genes from both mitochondrial genomes of mussels sampled at five locations worldwide, covering the whole M. trossulus range. The overall pattern of polymorphisms is compatible with the entirely postglacial history of the whole species, indicating a very deep bottleneck at last glacial maximum, with possible retention of the whole species in a single refugium, and the effective population size of no more than a few thousands. Both analyses of molecular variance and isolation with migration (IM) models point at the West Atlantic as the source of the European M. trossulus mussels, at least the ones who retained their native mtDNA. The hypothesis that this is an ongoing, human-mediated process was considered. To this end, comparison with the well-known case: the introduction of congeneric mussel, Mytilus galloprovincialis, from Mediterranean Sea to Asia was used. This introduction occurred within the last 100 years. The results inferred by the IM model suggest that the timing and structure of transatlantic migration of M. trossulus differs significantly from the M. galloprovincialis case: it is more than 1,000 years old and involves a much larger fraction of the ancestral population. Therefore, most likely, this invasion is not a human-mediated process.  相似文献   
95.
With about half of its territory being farmed, agriculture is the main land use in the European Union (EU). As over 10% of the total EU manufacturing output comes from the agri-food sector, it also is an economic factor of great importance. Moreover, EU policy in this sector has far-reaching consequences ranging from the EU's status as a global trade partner to landscape preservation and development. The LUMOCAP Policy Support System is targeted towards policy makers in the European Commission (EC) and its Member States (MS) and aims to provide support in the field of sustainable agricultural and rural development. To this end it incorporates an integrated model with socio-economic and bio-physical processes, operating at different spatial scales. For supporting integrated assessment, a large number of policy levers is included as inputs for these models and outputs are transformed into policy-relevant social, economic and environmental indicators. The whole system is framed in a flexible, modular and easy to use software package that is useable for process experts and policy-analysts alike.This paper describes the integrated model, the individual models and a first calibration of the system. It demonstrates the system's behaviour for typical scenario runs and concludes with a reflection on the current status of the system and some recommendations for further development.  相似文献   
96.
Electromagnetic field (EMF) measurements, for labor safety and environment protection purposes, are performed in the near-field. Inaccuracy of the far-field EMF measurements oscillates around ±1 dB or bit worse; in the near-field measurements, errors at the level of ±6 dB must be sometimes accepted. In the case of non-stationary EMF measurements, their sense may be changed from quantitative to qualitative ones. In order to make it possible an estimation of the non-stationary EMF measurement accuracy, it is proposed new method of the meters calibration. The method is based upon a standard excitation with identical signal as the measured one. A set for the purpose includes a pulse generator (of frequency and pulse rating identical with the radiation source) and computer-controlled amplitude modulator that reflects the radiation pattern of an antenna (e.g. radar one) and its rotations. Contrary to calibration using monochromatic continuous wave (CW) excitation, proposed method should be repeated for any radiation source. The disadvantage is compensated by a possibility to estimate (additional) error of the method. Calculations show it at the level of 10%.  相似文献   
97.
A steam injection pilot-scale experiment was performed on the unsaturated zone of a strongly heterogeneous fractured soil contaminated by jet fuel. Before the treatment, the soil was stimulated by creating sub-horizontal sand-filled hydraulic fractures at three depths. The steam was injected through one hydraulic fracture and gas/water/non-aqueous phase liquid (NAPL) was extracted from the remaining fractures by applying a vacuum to extraction wells. The injection strategy was designed to maximize the heat delivery over the entire cell (10 m × 10 m × 5 m). The soil temperature profile, the recovered NAPL, the extracted water, and the concentrations of volatile organic compounds (VOCs) in the gas phase were monitored during the field test. GC-MS chemical analyses of pre- and post-treatment soil samples allowed for the quantitative assessment of the remediation efficiency. The growth of the heat front followed the configuration of hydraulic fractures. The average concentration of total hydrocarbons (g/kg of soil) was reduced by ~ 43% in the upper target zone (depth = 1.5-3.9 m) and by ~ 72% over the entire zone (depth = 1.5-5.5 m). The total NAPL mass removal based on gas and liquid stream measurements and the free-NAPL product were almost 30% and 2%, respectively, of those estimated from chemical analyses of pre- and post-treatment soil samples. The dominant mechanisms of soil remediation was the vaporization of jet fuel compounds at temperatures lower than their normal boiling points (steam distillation) enhanced by the ventilation of porous matrix due to the forced convective flow of air. In addition, the significant reduction of the NAPL mass in the less-heated deeper zone may be attributed to the counter-current imbibition of condensed water from natural fractures into the porous matrix and the gravity drainage associated with seasonal fluctuations of the water table.  相似文献   
98.
In this work we present the usefulness of FT-Raman spectroscopy for microbiological analysis of textiles. This technique was used for non-destructive identification of Escherichia coli bacteria on cotton and polyester fabrics. It was possible to discriminate between infected and non-infected materials. Moreover, this technique allowed detection of detergent traces as well as investigation of the influence of microorganisms on different textiles. Raman analysis supported by chemometrics (cluster analysis and principal component analysis) was shown to be a method for identification of textiles with inoculum of microorganisms in a short time. The results can be potentially used in the fabric industry and related areas.  相似文献   
99.
Environmental Science and Pollution Research - In situ burning (ISB) is discussed to be one of the most suitable response strategies to combat oil spills in extreme conditions. After burning, a...  相似文献   
100.
The paper presents results of investigations of a novel method for diesel exhaust filtration in a fibrous filter supplemented by the external electrostatic field (FEF), which may be used to eliminate the occupational hazard near sources of diesel emission. The reported research follows the preliminary basic study of soot removal in such systems (Ciach, Sosnowski, & Podgórski, 1995), and is focused on the construction and testing of a prototype technical-scale FEF device. The results suggest a strong relation between applied voltage and filtration efficiency of the system and demonstrate the influence of aerosol precharging on the efficiency, which can be more than 95%.  相似文献   
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