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排序方式: 共有271条查询结果,搜索用时 15 毫秒
1.
Impacts on industry of Europe's emerging chemicals policy REACh   总被引:1,自引:0,他引:1  
For Europe, a new regime in chemicals regulation is about to start. After the proposal of the European Commission concerning the Registration, Evaluation and Authorization of Chemicals (REACh) passed its readings in the European Parliament and some differences with the European Council of Ministers were resolved, the regulation will come into force in June 2007. This paper is focused on the question how serious the cost burdens for industry induced by REACh will be, and whether the New European Member States (NMS) which joined the European Union in May 2004 will be able to cope with the regulation. This evaluation has been done by assessing the legislative, administrative and economic framework in New Member States and by analysing real business cases in companies. The empirical showcase business impact studies are at the same time of interest for companies of EU-15 states, other European countries who may implement the regulation, and even for exporters of raw materials and chemicals outside Europe, who will also have to comply with REACh if they market in the European Community. The results give no indications that REACh adoption will bring significant drawbacks to companies in the NMS. The emerging regulation will bring challenges for individual companies, especially for small and medium-sized ones, but for the European chemical industry as a whole, there is no question that it will be able to cope with REACh burdens without losing its global competitiveness.  相似文献   
2.
Life history costs of olfactory status signalling in mice   总被引:4,自引:0,他引:4  
Large body size confers a competitive advantage in animal contests but does not always determine the outcome. Here we explore the trade-off between short-term achievement of high social status and longer-term life history costs in animals which vary in competitive ability. Using laboratory mice, Mus musculus, as a model system, we show that small competitors can initially maintain dominance over larger males by increasing investment in olfactory status signalling (scent-marking), but only at the cost of reduced growth rate and body size. As a result they become more vulnerable to dominance reversals later in life. Our results also provide the first empirical information about life history costs of olfactory status signals. Received: 15 December 1999 / Revised: 6 June 2000 / Accepted: 24 June 2000  相似文献   
3.
Conservation decision makers commonly use project‐scoring metrics that are inconsistent with theory on optimal ranking of projects. As a result, there may often be a loss of environmental benefits. We estimated the magnitudes of these losses for various metrics that deviate from theory in ways that are common in practice. These metrics included cases where relevant variables were omitted from the benefits metric, project costs were omitted, and benefits were calculated using a faulty functional form. We estimated distributions of parameters from 129 environmental projects from Australia, New Zealand, and Italy for which detailed analyses had been completed previously. The cost of using poor prioritization metrics (in terms of lost environmental values) was often high—up to 80% in the scenarios we examined. The cost in percentage terms was greater when the budget was smaller. The most costly errors were omitting information about environmental values (up to 31% loss of environmental values), omitting project costs (up to 35% loss), omitting the effectiveness of management actions (up to 9% loss), and using a weighted‐additive decision metric for variables that should be multiplied (up to 23% loss). The latter 3 are errors that occur commonly in real‐world decision metrics, in combination often reducing potential benefits from conservation investments by 30–50%. Uncertainty about parameter values also reduced the benefits from investments in conservation projects but often not by as much as faulty prioritization metrics.  相似文献   
4.
Transaction costs in community-based resource management are incurred by households attempting to enforce property right rules over common resources similar to those inherent in private property rights. Despite their importance, transaction costs of community-based management of common pool resources (CPRs) are often not incorporated into the economic analysis of participatory resource management. This paper examines the transaction costs incurred by forest users in community forestry (CF) based on a survey of 309 households belonging to eight different forest user groups (FUGs) in the mid hills of Nepal. The analysis reveals that the average 'poor' household incurred Nepalese rupees (NRS) 1265 in transaction costs annually, while wealthier 'rich' households incurred an average of NRS 2312 per year. Although richer households bear higher proportions of such costs, transaction costs for CF management as a percentage of resource appropriation costs are higher for poorer households (26%) than those of middle-wealth (24%) or rich households (14%). There are also village differences in the level of transaction costs. The results show that transaction costs are a major component of resource management costs and vary according to socio-economic status of resource users and characteristics of the community.  相似文献   
5.
负外部成本内部化约束下的煤炭开采税费水平研究   总被引:1,自引:0,他引:1  
煤炭开采中面临严重的代际负外部性和生态环境负外部性问题,分别运用使用者成本法和直接市场法测算了煤炭资源开采中的代际负外部成本和生态环境负外部成本。根据两个负外部成本充分内部化的要求,提出煤炭开采中税费水平的调整目标。以2008年为例,煤炭开采中资源税的征收标准应由目前的从量0.3-5元/t(约从价1%)提至从价10%;开采吨煤应交的生态环境费用标准应由目前的24元/t提至64.23-68.47元/t,即每吨提高40.23-44.47元。综合资源税和生态环境费用的提高幅度,煤炭开采活动中的税费水平应提高约21-22个百分点;通过比较现行税费制度下煤炭开采企业实交的资源税费、生态环境税费总额与企业应交的资源、生态环境费用总额之间的差距,指出目前我国政府对开采企业隐性税费补贴的规模水平,根据价差法计算得出取消此部分税费补贴将可以削减3 653.69万tCO2排放。  相似文献   
6.
综合运用变异系数、泰尔指数及ESDA-GIS多种方法,在充分考虑传统经济影响因子的基础上,尝试引入经济发展生态成本指标,分析长江中游城市群经济综合发展水平与生态成本的空间匹配及演化模式。研究表明:经济综合发展水平高低聚集特征明显,空间极化现象是导致区域经济发展不平衡的主要原因;生态成本空间集聚现象以高高集聚和低低集聚为主,且呈现出高高集聚减少、低低集聚增多的现象,生态成本消耗有所改善;2001~2012年长江中游城市群市域经济综合发展水平与生态成本表现出越来越显著的差异化空间格局,呈现出由低经济综合发展水平-低生态成本过渡到高经济综合发展水平-高生态成本,进而发展到高经济综合发展水平-低生态成本的空间匹配模式的阶段性特征;高经济综合发展水平-高生态成本的经济发展模式仍在大部分城市中存在,经济与生态空间协调发展的潜力仍然很大。  相似文献   
7.
Nitrate leaching forms an important environmental problem because it causes pollution of groundwater and surface water, and adds to already problematic eutrophication. This study analyses the impact of reductions in nitrate leaching on land cover decisions of dairy farms, of which the activities make an important contribution to nitrate leaching. As the level of nitrate leaching depends on groundwater depth as well as on the supply of nitrogen, spatial variation in groundwater levels will cause a spatial variation in land cover under restrictions on nitrate leaching. A non-linear partial optimisation model for the economic and ecological aspects of the problem were used to show how land cover and dairy farms' financial balances change when nitrate losses are reduced. The model is spatially explicit, and describes nitrate leakage and yields of maize and grass as a function of groundwater depth, including the effects of various grazing systems. The model analyses the decisions of a risk neutral agent who minimises costs under the following constraints: (i) production, feed requirements and mass balances for fodder; (ii) constraints for nitrate leaching. Economic costs are attributed to increased costs of fodder and processing of manure when nitrate restrictions are tightened. An important result of the study is the variation in compliance costs and land cover for maize and grass production brought about by spatial variation in groundwater depth. While the effects are negligible for some shallow groundwater classes, it is extremely difficult in other classes – if not impossible – to obtain the EU standard of maximum admissible losses of 34 kg N ha–1 at low costs. The study shows an important reduction in land cover by maize.  相似文献   
8.
Summary. Jasmonic acid (JA) is a wound-related hormone found in most plants that, when applied exogenously, can induce increases in levels of chemical defenses in patterns similar to those induced by mechanical damage or insect feeding. Relative to responses to insect and pathogen attack, chemical responses of herbaceous plants to mammalian herbivore attack have been little studied. In a field experiment, we compared the effects of JA treatment and naturally occurring mammalian herbivory on the expression of trypsin inhibitors, glucosinolates, peroxidase activity and growth of wild mustard (Brassica kaber). Exogenous JA significantly increased trypsin inhibitor activity and glucosinolate concentration, and moderately increased peroxidase activity in the eighth true leaves of five-week-old plants, relative to untreated controls. In contrast, levels of these chemical defenses in the eighth true leaves or in regrowth foliage of plants that had ∼80% of their leaf area removed by groundhogs (Marmota monax) did not differ from that in undamaged and untreated controls. Although exogenous JA significantly elevated levels of chemical defenses, it did not affect height of plants through the season and only slightly reduced time to first flower. Groundhog herbivory significantly reduced height and delayed or abolished flowering, but these effects were not substantial unless coupled with apical meristem removal. We hypothesize that the lack of effect of groundhog herbivory on chemical defenses may be due in part to the speed and pattern of leaf area removal by groundhogs, or physiological constraints caused by leaf area loss. Despite having no effect on chemical defense production, leaf area loss by groundhogs was more costly to growth and fitness than the effects of JA application in this study, but only substantially so if coupled with apical meristem removal. We suggest that in general, costs of defense production in plants are likely to be minimal when compared to the risk of losing large amounts of leaf area or primary meristematic tissue. Thus, if they are effective at deterring herbivory, the benefits of inducible defense production likely outweigh the costs in most cases. Received 20 December 2000; accepted 3 May 2001  相似文献   
9.
The Fallacies of Concurrent Climate Policy Efforts   总被引:1,自引:0,他引:1  
Marian Radetzki 《Ambio》2010,39(3):211-222
Climate policy has assumed an extreme degree of urgency in the international debate in recent years. This article begins by taking a critical look at the scientific underpinnings of the efforts to stabilize the climate. It points to several serious question marks on the purported relationship between greenhouse gas emissions and global warming, and expresses distrust about claims of impending catastrophes related to rising sea levels, hurricanes, and spread of infectious disease. It then reviews the concurrent climate policy efforts and concludes that they are incoherent, misguided and unduly costly, and that they have so far had no perceptible impact on anthropogenic greenhouse gas emissions. The exceedingly ambitious policy plans currently under preparation suffer from similar fallacies. For these reasons, but also because of the remaining scientific doubts and the exorbitant costs that have to be incurred, skepticism is expressed about the preparedness to implement the climate policy plans currently on the table.  相似文献   
10.
ABSTRACT: Because of its importance and the perceived inability of private sector sources to meet water demands, many countries have depended on the public sector to provide water services for their populations. Yet this has resulted in many inefficient public water projects and in inadequate supplies of good quality and reliable water. Decentralization of water management, including the use of water markets, cannot solve all of these water problems, but it can improve the efficiency of water allocation. When given adequate responsibility and authority, water user associations have effectively taken over water management activities at a savings to tax payers. Moreover, water markets add the potential benefit of improving water efficiency within a sector as well as providing a mechanism for reallocating water among sectors. The key question involves developing innovative mechanisms for reducing the transaction costs of organizing water users and of making water trades. Water rights need to be established which are recorded, tradable, enforceable, and separate from land if markets are to operate effectively. Also, institutions are needed that effectively resolve conflicts over water rights, including third party impacts and water quality concerns.  相似文献   
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