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81.
Coal-based power generates large quantities of coal ash in South Korea. However, coal ash recycling is still inactive and most wasted coal ash is buried in landfills. Recently, beneficial uses of coal ash such as in mine reclamation sites has been increasingly considered; however, as a result of legal limitations due to environmental concerns, the utilization of coal ash at mine reclamation sites has procrastinated. Consequently, to resolve this issue, the relevant environmental impact of coal ash must be considered. Therefore, a leaching assessment framework to assess the environmental impact of coal ash utilization at South Korean mine reclamation sites is presented. The framework was used to identify leaching mechanisms and support an assessment of the environmental impact of coal ash usage at mine reclamation sites in South Korea. This framework could provide guidance with regard to designing more realistic leaching procedures appropriate for all mine conditions and could support the development of regulations and protocols for future environment-friendly coal ash usage.  相似文献   
82.
Plastic packaging wastes increased considerably in recent decades, raising a major and serious public concern on political, economical and environmental levels. Dealing with this kind of problems is generally done by landfilling and energy recovery. However, these two methods are becoming more and more expensive, hazardous to the public health and the environment. Therefore, recycling is gaining worldwide consideration as a solution to decrease the growing volume of plastic packaging wastes and simultaneously reduce the consumption of oil required to produce virgin resin. Nevertheless, a major shortage is encountered in recycling which is related to the sorting of plastic wastes. In this paper, a feasibility study was performed in order to test the potential of an innovative approach combining mid infrared (MIR) spectroscopy with independent components analysis (ICA), as a simple and fast approach which could achieve high separation rates. This approach (MIR-ICA) gave 100% discrimination rates in the separation of all studied plastics: polyethylene terephthalate (PET), polyethylene (PE), polypropylene (PP), polystyrene (PS) and polylactide (PLA). In addition, some more specific discriminations were obtained separating plastic materials belonging to the same polymer family e.g. high density polyethylene (HDPE) from low density polyethylene (LDPE). High discrimination rates were obtained despite the heterogeneity among samples especially differences in colors, thicknesses and surface textures. The reproducibility of the proposed approach was also tested using two spectrometers with considerable differences in their sensitivities. Discrimination rates were not affected proving that the developed approach could be extrapolated to different spectrometers. MIR combined with ICA is a promising tool for plastic waste separation that can help improve performance in this field; however further technological improvements and developments are required before it can be applied at an industrial level given that all tests presented here were performed under laboratory conditions.  相似文献   
83.
Due to the impacts of commercial fishing on elasmobranchs, future research and management necessitates reliable and accurate information on life history. For females, maturity assessment is limited to dissection, and it is not desirable to be removing large numbers in order to assess the reproductive characteristics of a population. The present study evaluated ultrasonography as a potential, non-lethal method for assessing the maturity status of two oviparous elasmobranchs, the thornback ray (Raja clavata) and small-spotted catshark (Scyliorhinus canicula). Ultrasound permitted visualisation and measurement of the ovary in R. clavata, and the shell gland, ovarian follicles and egg capsules within the oviducts for S. canicula. With the exception of the ovary in R. clavata, the dimensions of these structures on the sonograms were directly corroborated by in situ measurements, and ultrasound was verified as an accurate and reliable method of making quantitative and qualitative assessments of these internal reproductive structures.  相似文献   
84.
85.
With more and more organizations seeking opportunities to generate benefits beyond compliance from environmental management activities, the challenges for environmental directors today is to develop and implement an environmental strategy that links environmental performance with the overarching strategic business goals of the organization. Organizations today are looking for opportunities to develop environmental management solutions that not only address the concerns of regulatory stakeholders, but also provide opportunities to improve operating efficiency and financial performance, enhance customer satisfaction, sustain market growth, and enhance goodwill, to satisfy the demands of a broader set of stakeholder groups including customers, investors, and employees. To achieve broader benefits from environmental management investments, this article shows how organizations must first develop a methodology for aligning their environmental management activities with the organization's strategic business goals and create a plan for systematically managing continuous improvement to achieve these goals. The second challenge is to implement this strategy at the business unit and facility level in a manner which integrates environmental management activities with an organization's core business processes to achieve improved product and service performance.  相似文献   
86.
Fire hazards at the urban-wildland interface: What the public expects   总被引:2,自引:0,他引:2  
Urban-wildland issues have become among the most contentious and problematic issues for forest managers. Using data drawn from surveys conducted by the authors and others, this article discusses how public knowledge and perceptions of fire policies and fire hazards change over time, the kinds of policy responses homeowners prefer as a way of preventing fire hazards at the urban-wildland interface, and how citizens view their own obligations as participants in interface issues. These data show that public attitudes toward fire have changed significantly over the past two decades and that educating the public about fire and the managers' use of fire can have positive effects on behavior. Yet, modifying the individual's behavior in regard to interface fire risks must also deal with important issues of individual incentives, the distribution of costs, and unanticipated policy impacts.  相似文献   
87.
Fish is an important constituent of the Lebanese diet. However, very little attention in our area is given to bring awareness regarding the effect of the toxicity of mercury (Hg) mainly through fish consumption. This study aimed to report analytical data on total mercury levels in several fish species for the first time in thirty years and to also made individuals aware of the presence and danger from exposure to mercury through fish consumption. Fish samples were selected from local Lebanese markets and fisheries and included 94 samples of which were fresh, frozen, processed, and canned fish. All values were reported as microgram of mercury per gram of fish based on wet weight. The level of mercury ranged from 0.0190 to 0.5700 μg/g in fresh samples, 0.0059 to 0.0665 μg/g in frozen samples, and 0.0305 to 0.1190 μg/g in canned samples. The data clearly showed that higher levels of mercury were detected in local fresh fish as opposed to other types thus placing consumers at higher risk from mercury exposure. Moreover, the data revealed that Mallifa (yellowstripe barracuda/Sphyraena chrysotaenia), Sargous (white seabream/Diplodus sargus), Ghobbos (bogue/Boops hoops), and shrimp (Penaeus sp.) were among the types containing the highest amounts of mercury. On the other hand, processed fish such as fish fillet, fish burger, small shrimp and crab are found to contain lower levels of mercury and are associated with lower exposure risks to mercury. Lebanese population should therefore, be aware to consume limited amounts of fresh local fish to minimize exposure to mercury.  相似文献   
88.
Evolutionarily stable strategies of age-dependent sexual advertisement   总被引:5,自引:0,他引:5  
In various models of sexual selection mediated by the viability indicator (“good genes”) mechanism, a sexually selected trait will truly reflect male quality if its expression is costly for the male. However, in long-lived species, the expression of a trait often increases with age while the genotype of the male remains unchanged. This fact may obscure the indicator mechanism. Hitherto, game theory models of honesty in sexual advertisement have not taken life-history effects into account, whereas life-history models of reproductive effort have only seldom considered the dependence of mating success on the actions of other individuals. Here, the two approaches are combined, and I examine whether honesty is maintained if males can divide their advertisement effort over their lifetime. The model shows that an increase in the expression of the sexually selected trait over several years is an evolutionarily stable strategy (ESS) under a wide range of situations, so that a correlated preference for old age can emerge through a viability indicator mechanism. Honesty in the strict sense is not preserved: an optimally behaving low-quality male will in some cases advertise more than a high-quality male of equal age, to the extent that the strongest advertisement found in the population can be associated with a low-quality male. Due to life-history trade-offs, however, honesty in an average sense holds true over the lifetime of individuals: “cheater” age classes will remain small enough, that a female will obtain a higher expected mate quality if she trusts in the trait as an indicator of viability. Received: 25 June 1996 / Accepted after revision: 15 April 1997  相似文献   
89.
Summary. Some plant volatiles are produced in response to herbivory of several insect species, including heliothine larvae. In the present study of female heliothine moths, four co-located receptor neurone types were identified, of which three types responded strongest to the inducible compounds E--ocimene, E,E--farnesene and E,E-TMTT, respectively. The fourth type responded strongest to geraniol, which is a common floral volatile. The narrow tuning of each receptor neurone type was demonstrated by responses to a few structurally-related monoterpenes, sesquiterpenes, homo-terpenes and monoterpene alcohols, respectively, out of hundreds of plant constituents tested. The four neurone types showed the same relation of spike amplitudes and ranking of effective compounds in the three heliothine species; the polyphagous Heliothis virescens and Helicoverpa armigera and the oligophagous Helicoverpa assulta. The results indicate the presence of functionally similar types of plant odour-receptor neurones in the three related species, and suggest conservation or reappearance of functionally similar olfactory receptors in related species, independent of the evolution of polyphagy and oligophagy.  相似文献   
90.
There is genetic variation in the female mating rate in the green-veined white butterfly (Pieris napi), and females benefit from male ejaculates that contain both sperm and accessory gland substances. Although polyandry corresponds to higher lifetime fecundity than monandry, some females abstain from remating irrespective of the number of available mates. Explaining genetic variation in mating rates requires that monandrous females perform better than polyandrous ones under some conditions. We experimentally explored the reproductive performance of females either with a low or high intrinsic mating rate by allowing them to mate, feed, and lay eggs freely in a laboratory. Individual females followed different life histories: during the early days of reproduction, females with a low mating rate produced more eggs than females with a high mating rate. Hence, refraining from the benefits of multiple mating may be beneficial, if the time for reproduction is limited, or other female traits associated with polyandry are traded off against longevity. Given the day length of 10 h, a model shows that even if polyandrous females enjoy higher lifetime reproductive success, changeable and unpredictable weather will favor monandry if each period of suitable weather lasts, on average, less than 5 days. Thus, a combination of life history cost and unpredictability of fitness may explain the maintenance of monandry in the wild. Our results are also consistent with the observation that frequency of monandry increases with latitude.  相似文献   
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