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921.
922.
923.
Stabilization of CO2 atmospheric concentrations requires practical strategies to address the challenges posed by the continued use of coal for baseload-electricity production. Over the next two decades, CO2 capture and sequestration (CCS) demonstration projects would need to increase several orders of magnitude across the globe in both size and scale. This task has several potential barriers which will have to be accounted for. These barriers include those that have been known for a number of years including safety of subsurface sequestration, pore-space competition with emerging activities like shale gas production, legal and regulatory frameworks, and public acceptance and technical communication. In addition water management is a new challenge that should be actively and carefully considered across all CCS operations. A review of the new insights gained on these previously and newly identified challenges, since the IPCC special report on CCS, is presented in this paper. While somewhat daunting in scope, some of these challenges can be addressed more easily by recognizing the potential advantageous synergies that can be exploited when these challenges are dealt with in combination. For example, active management of water resources, including brine in deep subsurface formations, can provide the additional cooling-water required by the CO2 capture retrofitting process while simultaneously reducing sequestration leakage risk and furthering efforts toward public acceptance. This comprehensive assessment indicates that water, sequestration, legal, and public acceptance challenges ought to be researched individually, but must also be examined collectively to exploit the promising synergies identified herein. Exploitation of these synergies provides the best possibilities for successful large-scale implementation of CCS.  相似文献   
924.
925.
With increased outsourcing and environmental consciousness, this paper presents an analytic network process (ANP) approach to incorporate the issue of hazardous substance management (HSM) into supplier selection. In this study, identification of criteria of HSM competence is categorized into four dimensions, a multi-criteria decision model is proposed. ANP is then applied to supplier selection and is characterized by interdependencies among decision structure components. An illustrative example in an electronics company is presented to demonstrate how to select a most appropriate supplier in accordance with the requirements of hazardous substance for environmental regulations.  相似文献   
926.
Abstract: The Galápagos Islands harbor some of the least impacted marine ecosystems in the tropics, but there are indications that local artisanal fishing is affecting exploited marine communities. To quantify these effects, I sampled communities of fishes and sea urchins at a number of heavily fished and lightly fished sites throughout the central islands of the archipelago. Sites were selected based on information collected as part of a local fisheries monitoring study and standardized across a number of abiotic factors. Abundance and biomass of the primary target species were significantly lower in the heavily fished sites than in the lightly fished sites. Community structure also differed between heavily and lightly fished sites. Cluster analyses of the full community of fishes and a subset of nontarget fishes revealed that sites within a treatment were more similar to one another than sites between treatments. Herbivorous fishes tended to be lower in abundance and sea urchins tended to be higher in abundance in heavily fished sites, but these differences were not significant. My results are encouraging in that the direct effects of artisanal fishing are limited to the primary target species, which probably results from a high specificity of fishing gear. The differences in community structure, however, suggest that artisanal fishing also has cascading effects on noncommercial species throughout the community. An improved understanding of important ecological interactions, increased ecological and fishery monitoring, and effective precautionary management are needed to ensure that human effects in these waters remain minimal.  相似文献   
927.
Understanding the dynamics of population recovery is particularly complex when an organism has multiple, remote breeding and feeding grounds separated by one of the longest known migration routes. This study reports on the most comprehensive assessment of humpback whale (Megaptera novaeangliae) movements between remote Antarctic waters south of New Zealand and east Australia (EA), and the migratory corridors and breeding grounds of Australia and Oceania. A total of 112 individual whales were identified; 57 from microsatellites and 61 by fluke with 23 % (n = 26) matched to sites outside Antarctica. Despite large datasets from other southern regions being included in the comparison, the whales were predominantly linked to EA (n = 24). Only two matches to the Oceania catalogues directly north was surprising; therefore the primary feeding grounds of these endangered whales still remain unknown. The confirmation of the Balleny Islands as an important feeding ground for EA whales could provide an insight into reasons behind the rapid recovery of this population. Determining the feeding grounds of Oceania’s whales may explain whether prey energetics or migration length are limiting factors to their recovery and will allow an understanding of future ecosystem changes in these whales.  相似文献   
928.
The persistence of behavioral types in situ and the drivers of persistence are central to predicting the ecological effects of intraspecific behavioral variation. We surveyed individual refuge use of mud crabs (Panopeus herbstii), a behavior related to the strength of a trait-mediated trophic cascade in oyster reefs, in the absence and presence of toadfish (Opsanus tau) predation threat. We then released these crabs into the field and using mark-recapture, measured the repeatability of this behavior in the absence and presence of threat, and how behavioral change was affected by time in the field (a month on average, up to 81 days), crab size, and sex. Because crabs exhibited some evidence of a circatidal rhythm in refuge use, we also tested how tidal height during observation influenced behavioral change. Predation threat increased refuge use, and small crabs used the refuge more than large crabs, particularly under threat. In recaptured crabs, refuge use was more repeatable under threat. Neither time in the field, crab size, crab sex, nor tidal height had any effect on behavioral change. Our results support the non-mutually exclusive hypotheses that (1) prey organisms in the presence, rather than absence, of predation threat should exhibit less behavioral variability because the fear of dying (a severe fitness consequence) should take precedence over less immediately important influences on behavior (e.g., hunger) and that (2) individual behaviors tied to fixed traits (e.g., the body size dependence of refuge use under threat in this study), rather than variable traits, should be more repeatable over time.  相似文献   
929.
A novel hazard identification methodology applied to process systems is presented in this paper. This blended hazard identification (BLHAZID) methodology blends two different types of HAZID methods: the function-driven and component-driven approach. The BLHAZID method is based on a conceptual framework called the Functional Systems Framework, which describes structure–function–goal relationships in process systems.The goals of the BLHAZID methodology are to generate outcomes that contain a high coverage of hazards, describe detailed failure causality in process systems and express this knowledge in a structured form for effective reused in subsequent applications, such as fault diagnosis, operator training, design reviews, fault and event tree construction and hazard updates to satisfy major hazard facility requirements.Both the BLHAZID methodology and the Functional Systems Framework were developed with involvement and advice from two major industrial partners. An industrial case study of a benzene saturation unit is presented to illustrate how the BLHAZID methodology operates in practice.  相似文献   
930.
The accommodation sector is the most demanding energy consumer among all building stock categories. This study quantifies an international tourist hotel in Taiwan to holistically estimate the greenhouse gas emissions of hotel accommodation services through a complete life cycle inventory. The study also investigates the difference between the carbon emissions of the baseline and reduction years to understand the effects of carbon emission reduction on the hotel industry. Results show that energy consumption is the main source of carbon footprint. However, the carbon emissions of other activities, such as the production and transportation of hotel amenities and laundry services, are 15.90% for the baseline year and 16.03% for the reduction year. These values are larger than the 5% cutoff rule according to PAS 2050. Thus, these factors should also be considered in assessing the carbon emissions of accommodation services. Hotel occupancy rate significantly affects carbon emissions during a one-night stay in a standard room as the functional unit. The selection of the functional unit should be considered in the hotel strategy. Although this case study involves an international tourist hotel in Taiwan, the findings and recommendations for improvements can be applied elsewhere.  相似文献   
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