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821.
Large-scale exploitation of fossil fuels and nuclear power can have an adverse effect on the human and natural environment. That need not be the case, if the effect on the environment is carefully assessed to ensure the development of a sustainable approach. This paper examines the process of environmental impact assessment (EIA) for coal from an international perspective. The concept of EIA is not new. A formalized process of EIA was introduced in the USA in 1970, and more recently similar legislation has been implemented in other countries. The member states of the European Community are required to adopt EIA regulations, as set out in Directive 85/337/EEC. Elsewhere, in Japan and Australia, there are requirements for EIA and a growing need for the process can be seen in developing countries. A comparison is made of the EIA process for coal in the international arena, and exemplary procedures are highlighted. Potential problems such as delays, modifications and additional costs are analysed, and the benefits of EIA, both to industry and environment, are discussed. A database of coal-related EIA would facilitate an exchange of information on the subject.  相似文献   
822.
ABSTRACT: In addition to measuring the quantity of stormwater runoff generated during ten rainfall events from the Vehicle Assembly Building (VAB) area of Kennedy Space Center (KSC), historical rainfall records were also used for determining the feasibility of implementing a program of stormwater recycling to air conditioning cooling towers. It was projected that 0.182 million gallons per day (MGD) of runoff would be generated from the VAR area during a year of average rainfall (48 inches); only 0.117 MGD is required for coolant makeup water in the VAR area. Due to the seasonal variations in rainfall, stormwater recycling may not always meet all the cooling water demands.  相似文献   
823.
北京PM10中矿物颗粒的微观形貌及粒度分布   总被引:12,自引:1,他引:12  
使用高分辨率环境扫描电镜和图像分析技术对北京PM10中矿物颗粒的微观形貌和粒度分布特征进行了研究.结果表明,北京PM10中的矿物颗粒按其形貌、组成特点可以分为单矿物和矿物集合体2类;矿物颗粒多以不规则的形态出现;形态规则的矿物主要是硫酸盐类矿物,是大气化学反应的产物,形态不规则的矿物是来自扬尘的原生矿物.不同类型污染产生的PM10中矿物颗粒的粒度分布特征表现不同,在沙尘暴样品和道路扬尘样品中矿物颗粒的粒度峰值在1~2.5μm;在局地扬尘的样品中,矿物颗粒的粒度较粗.主要分布在1—2.5μm和2.5—10μm.  相似文献   
824.
825.
Understanding the functional significance of shelter for animal populations requires knowledge of the behavioural mechanisms that govern the dynamics of shelter use. Exploitation of shelters may be impeded by mutual interference, yet interference competition can be difficult to distinguish from exploitation competition. We used bullheads (Cottus gobio) as a model system of mobile fish to investigate the effect of intraspecific competition on shelter use. A series of field experiments was conducted under controlled conditions of shelter availability and population density. For each experiment, the location of each individual fish was observed over a period of 10 days. We then constructed a continuous-time Markov-chain model for the movement of fish between shelters and the open stream, which explicitly parameterised exploitation competition and interference competition for shelter and which accounted for two different size-classes of fish. By using a stochastic rather than a deterministic model, we were able to account for the distribution of fish across shelters, and not just the average occupation. Analysis of the model showed strong evidence of exploitation competition, which was highly dependent on body size, and an increased departure rate from shared shelters. Over and above exploitation, interference competition limited the ability of unsheltered fish to colonise vacant shelters at high population densities. Different formulations of the interference competition were compared using the Akaike Information Criterion. The formulation that best fitted the observations modelled interference competition as an increasing function of average shelter occupancy rather than population density per se.  相似文献   
826.
Carbon labels inform consumers about the amount of greenhouse gases (GHGs) released during the production and consumption of goods, including food. In the future consumer and legislative responses to carbon labels may favour goods with lower emissions, and thereby change established supply chains. This may have unintended consequences.We present the carbon footprint of three horticultural goods of different origins supplied to the United Kingdom market: lettuce, broccoli and green beans. Analysis of these footprints enables the characterisation of three different classes of vulnerability which are related to: transport, national economy and supply chain specifics.There is no simple relationship between the characteristics of an exporting country and its vulnerability to the introduction of a carbon label. Geographically distant developing countries with a high level of substitutable exports to the UK are most vulnerable. However, many developing countries have low vulnerability as their main exports are tropical crops which would be hard to substitute with local produce.In the short term it is unlikely that consumers will respond to carbon labels in such a way that will have major impacts in the horticultural sector. Labels which require contractual reductions in GHG emissions may have greater impacts in the short term.  相似文献   
827.
Regional Higher Education Institutions (HEIs) may contribute significantly to the promotion of sustainability through several means connected with their functioning. Nevertheless, several challenges can present themselves during the planning and implementation of such initiatives. The aim of this paper is to underline these limitations through the relevant literature and highlight their main consequences on the achievement of sustainability. An empirical study, investigating the perception of students regarding the constraints to achieving sustainability in a regional university of Greece, was conducted and is discussed in relation to the university's specific characteristics – its fragmented nature with campuses situated on five Aegean islands, its public status as well as its role in creating and dispersing knowledge in less developed areas of the country.  相似文献   
828.
To control water impairment in urban stormwater, it is important to evaluate changing patterns of water quality parameters in stormwater runoff. Thus, the authors performed a series of experiments to investigate the dynamics of common water parameters during storm events in semi-arid areas, with multiple samples collected and analyzed in field stormwater applications. At this field monitoring site within McAuliffe Park, McAllen, Texas, in the United States, a storm event increased the concentrations of Escherichia coli (E. coli), but this event represented a decreasing trend over the entire event period. Besides, peak intensity of different pollutants in the stormwater runoff occurred at different times other than at any peak flows, representing a complexity of the temporal and spatial measurements. Multi-sample perevent approaches recommended based on the complexity of the hydrograph and different peak intensity times of pollutants. In addition, high bacteria and total suspended solids (TSS) concentrations in the initial stage of the storm event should be considered when designing Best Management Practices (BMPs) and Low Impact Developments (LIDs). New strategies and solutions for addressing ecohydrological challenges should be proposed to avoid collateral damages to their both common wealth in ecosystems and human well-beings.  相似文献   
829.
Research has revealed that women’s self-perceived attractiveness positively predicts preferences for male facial and vocal masculinity, particularly in the context of long-term relationships. Other research has demonstrated that women who perceive themselves to be less healthy prefer male masculinity more than do women who may be healthier. As self-perceived health may predict self-perceived attractiveness, previous findings may appear to be contradictory. Therefore, we compared the effects of self-perceived attractiveness and self-perceived health on vocal masculinity preferences in long- and short-term relationship contexts. We found that although self-perceived health and attractiveness were positively correlated, self-rated attractiveness positively predicted long-term vocal masculinity preferences, whereas self-rated health negatively predicted short-term vocal masculinity preferences. While health and attractiveness may share a common basis, here we show independent potentially adaptive relationships with preferences based on relationship context. Such preferences are potentially adaptive as (a) masculine men may pass on inheritable immunity to infection to their offspring, which may be a relatively greater benefit for women in poor health; and (b) masculine men may be more likely to invest in relationships and offspring of relatively attractive women, decreasing the cost of choosing a masculine long-term partner for attractive women. These data resolve a potential conflict between health and attractiveness influences on the attractiveness of masculinity and highlight sophisticated individual differences in preferences.  相似文献   
830.
Historical processes constrain patterns in global diatom diversity   总被引:8,自引:0,他引:8  
There is a long-standing belief that microbial organisms have unlimited dispersal capabilities, are therefore ubiquitous, and show weak or absent latitudinal diversity gradients. In contrast, using a global freshwater diatom data set, we show that latitudinal gradients in local and regional genus richness are present and highly asymmetric between both hemispheres. Patterns in regional richness are explained by the degree of isolation of lake districts, while the number of locally coexisting diatom genera is highly constrained by the size of the regional diatom pool, habitat availability, and the connectivity between habitats within lake districts. At regional to global scales, historical factors explain significantly more of the observed geographic patterns in genus richness than do contemporary environmental conditions. Together, these results stress the importance of dispersal and migration in structuring diatom communities at regional to global scales. Our results are consistent with predictions from the theory of island biogeography and metacommunity concepts and likely underlie the strong provinciality and endemism observed in the relatively isolated diatom floras in the Southern Hemisphere.  相似文献   
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