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331.
More and more countries are incorporating the instrument of emissions trading into their national climate policies. This emerging mosaic of emissions trading schemes (ETS) raises the question of whether they should be linked with each other. From an economic point of view, linking of domestic schemes is supposed to increase the economic efficiency of carbon markets. In addition, linking is also expected by some to yield substantial political benefits in terms of the evolution of the UNFCCC/Kyoto regime. However, these optimistic prospects are based on a best-case scenario where all major countries establish environmentally effective emissions trading systems and then link them with each other. Real-life politics might develop rather differently. This paper therefore examines to what extent the current status of emissions trading in industrialised countries provides a basis for reinforcing and moving forward the international climate regime through linking domestic ETS. After comparing emerging emissions trading schemes from an institutional perspective, it emerges that not only emissions trading is at a very early stage in most countries, in addition the emerging systems are probably going to be designed very differently from the EU ETS. While for some design features such as the coverage design differences do not matter, there are some areas where the plans in many non-EU countries look crucially different from the EU system. The outlook for a linked international ETS is therefore currently still very uncertain. Given this state of affairs, the EU should pro-actively engage with the non-EU countries to try to harmonise their developing national emissions trading schemes with the EU ETS, widely disseminate the lessons it has learned from the EU ETS, strongly make the case for environmental integrity and at the same time make clear that systems that want to link to the EU ETS will need to meet certain quality criteria.
Ralf SchüleEmail:
  相似文献   
332.
Social work force distribution in honeybee colonies critically depends on subtle adjustments of an age-related polyethism. Pheromones play a crucial role in adjusting physiological and behavioral maturation of nurse bees to foragers. In addition to primer effects of brood pheromone and queen mandibular pheromone—both were shown to influence onset of foraging—direct worker–worker interactions influence adult behavioral maturation. These interactions were narrowed down to the primer pheromone ethyl oleate, which is present at high concentrations in foragers, almost absent in young bees and was shown to delay the onset of foraging. Based on chemical analyses, physiological recordings from the antenna (electroantennograms) and the antennal lobe (calcium imaging), and behavioral assays (associative conditioning of the proboscis extension response), we present evidence that ethyl oleate is most abundant on the cuticle, received by olfactory receptors on the antenna, processed in glomeruli of the antennal lobe, and learned in olfactory centers of the brain. The results are highly suggestive that the primer pheromone ethyl oleate is transmitted and perceived between individuals via olfaction at close range.  相似文献   
333.
Given the wide diversity of data services provided to national water management agencies, the Group on Earth Observations (GEO) in collaboration with the Committee on Earth Observation Satellites (CEOS) developed the approach described in the report, Implementing the GEOSS Water Strategy—From Observations to Decisions to develop more coherent and equitable data services for water management through the use of Earth observations. Among other water resource issues, it recognized the need to enhance data-enriched water management services to support decision making related to drought monitoring, flood warning, tracking and improving sustainable development and monitoring and ameliorating the impacts of climate change. Needs associated with the Strategy's four themes: improved data acquisition for essential water variables, research and product development, interoperability and coordination, and capacity development and decision support, are reviewed. Responses to the recommendations have been undertaken by GEO, led by its Global Water Sustainability (GEOGloWS) initiative which includes NASA contributions, CEOS, and the Global Terrestrial Network for Hydrology (GTN-H). Progress on the themes is reviewed and benefits of these developments for international and US water management are identified. The commentary concludes with a summary of what has been achieved, what remains to be done, and the priority focus areas for implementation in the final year of the Strategy.  相似文献   
334.
Milcu A  Partsch S  Scherber C  Weisser WW  Scheu S 《Ecology》2008,89(7):1872-1882
The role of species and functional group diversity of primary producers for decomposers and decomposition processes is little understood. We made use of the "Jena Biodiversity Experiment" and tested the hypothesis that increasing plant species (1, 4, and 16 species) and functional group diversity (1, 2, 3, and 4 groups) beneficially affects decomposer density and activity and therefore the decomposition of plant litter material. Furthermore, by manipulating the densities of decomposers (earthworms and springtails) within the plant diversity gradient we investigated how the interactions between plant diversity and decomposer densities affect the decomposition of litter belonging to different plant functional groups (grasses, herbs, and legumes). Positive effects of increasing plant species or functional group diversity on earthworms (biomass and density) and microbial biomass were mainly due to the increased incidence of legumes with increasing diversity. Neither plant species diversity nor functional group diversity affected litter decomposition, However, litter decomposition varied with decomposer and plant functional group identity (of both living plants and plant litter). While springtail removal generally had little effect on decomposition, increased earthworm density accelerated the decomposition of nitrogen-rich legume litter, and this was more pronounced at higher plant diversity. The results suggest that earthworms (Lumbricus terrestris L.) and legumes function as keystone organisms for grassland decomposition processes and presumably contribute to the recorded increase in primary productivity with increasing plant diversity.  相似文献   
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Regional Environmental Change - Planning for the future requires a detailed understanding of how climate change affects a wide range of systems at spatial scales that are relevant to humans....  相似文献   
338.
Recent measurements at different locations suggest that the emission of mercury from soils may play a more pronounced role in the global mercury cycle as suggested by global emission inventories and global mercury cycling models. For up scaling and modelling of mercury emissions from soils a comprehensive assessment of the processes controlling the emission of mercury from soils is imperative. We have developed a laboratory flux measurement system (LFMS) to study the effect of major environmental variables on the emission of mercury under controlled conditions. We have investigated the effects of turbulent mixing, soil temperature and solar radiation on the emission of mercury from soils. The emission of mercury from soils is constant over time under constant experimental conditions. The response of the mercury emission flux to variations of the atmospheric transfer parameters such as turbulence requires a rapid adjustment of the equilibrium that controls the Hg(o) concentration in the soil air. It has been shown that the light-induced flux is independent of the soil temperature and shows a strong spectral response to UV-B.  相似文献   
339.
The draft of the German guideline to calculate automobile exhaust dispersion is explained. It contains a two-stage-system: For first quick estimates the guideline contains the simple models MLuS and STREET. In case these models are not applicable or their results shows concentration levels close to the air quality standards, the more complex models PROKAS_V and MISKAM are recommended. PROKAS_V is a Gaussian plume model, MISKAM is a 3-dimensional microscale non hydrostatic flow model for built-up areas with an Eulerian dispersion model. The guideline comprises cases in rural areas without or with few adjacent buildings as well as urban areas with buildings near the roads. The contribution gives information about the models, typical results and some of the problems showing up presently.  相似文献   
340.
In the framework of ethical social choice theory, sustainability is justified by efficiency and equity as ethical axioms. These axioms correspond to the Suppes–Sen grading principle. In technologies that are productive in a certain sense, the set of Suppes–Sen maximal utility paths is shown to equal the set of non-decreasing and efficient paths. Since any such path is sustainable, efficiency and equity can thus be used to deem any unsustainable path as ethically unacceptable. This finding is contrasted with results that seem to indicate that an infinite number of generations cannot be treated equally.  相似文献   
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