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The coastline of the state of Rio Grande do Sul (Brazil) is used annually as a migratory route by a number of seabird species. Thirteen surveys were carried out between July 1997 and July 1998 to obtain information on the diet of Puffinus gravis, Puffinus griseus, and Puffinus puffinus along the coast of Rio Grande do Sul. Sampling efforts focused on dead beach-cast specimens. One hundred twenty-one stomach content analyses were performed on P. gravis from a total of 238 specimens; 17 stomach content analyses were performed on P. griseus from a total of 54 specimens; and 25 stomach content analyses were performed on 25 P. puffinus from a total of 61 dead specimens. Cephalopods were the main prey found in the stomachs of the three species and were present in 96% of the P. gravis stomachs. The following cephalopods were observed: Ommastrephidae, Gonatus antarcticus, Gonatus sp., Lycoteuthis lorigera, Lycoteuthis sp., Histioteuthis sp., Cycloteuthis sp., Loligo plei, Loligo sanpaulensis, Sepiidae, and Argonauta nodosa. The latter was the most abundant species in the three species of Puffinus. The following fish were identified from otoliths: Porichthys porosissimus, Ctenosciaena gracilicirrhus, Paralonchurus brasiliensis, Cynoscion guatucupa, and Trichiurus lepturus. There was also a high incidence of synthetic materials such as plastic, polyethylene and rubber.  相似文献   
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Environmental Science and Pollution Research - The lignocellulose biorefinery industry has assumed an important role within the current scenario. Lignin is an abundant and available biopolymer and...  相似文献   
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Assessments of past environmental policies—termed accountability studies—contribute important information to the decision-making process used to review the efficacy of past policies, and subsequently aid in the development of effective new policies. These studies have used a variety of methods that have achieved varying levels of success at linking improvements in air quality and/or health to regulations. The Health Effects Institute defines the air pollution accountability framework as a chain of events that includes the regulation of interest, air quality, exposure/dose, and health outcomes, and suggests that accountability research should address impacts for each of these linkages. Early accountability studies investigated short-term, local regulatory actions (for example, coal use banned city-wide on a specific date or traffic pattern changes made for Olympic Games). Recent studies assessed regulations implemented over longer time and larger spatial scales. Studies on broader scales require accountability research methods that account for effects of confounding factors that increase over time and space. Improved estimates of appropriate baseline levels (sometimes termed “counterfactual”—the expected state in a scenario without an intervention) that account for confounders and uncertainties at each link in the accountability chain will help estimate causality with greater certainty. In the direct accountability framework, researchers link outcomes with regulations using statistical methods that bypass the link-by-link approach of classical accountability. Direct accountability results and methods complement the classical approach. New studies should take advantage of advanced planning for accountability studies, new data sources (such as satellite measurements), and new statistical methods. Evaluation of new methods and data sources is necessary to improve investigations of long-term regulations, and associated uncertainty should be accounted for at each link to provide a confidence estimate of air quality regulation effectiveness. The final step in any accountability is the comparison of results with the proposed benefits of an air quality policy.

Implications: The field of air pollution accountability continues to grow in importance to a number of stakeholders. Two frameworks, the classical accountability chain and direct accountability, have been used to estimate impacts of regulatory actions, and both require careful attention to confounders and uncertainties. Researchers should continue to develop and evaluate both methods as they investigate current and future air pollution regulations.  相似文献   

105.
Storm water runoff is increasingly assessed for fecal indicator organisms (e.g., Escherichia coli, E. coli) and its impact on contact recreation. Concurrently, use of autosamplers along with logistic, economic, technical, and personnel barriers is challenging conventional protocols for sample holding times and storage conditions in the field. A common holding time limit for E. coli is 8 h with a 10 °C storage temperature, but several research studies support longer hold time thresholds. The use of autosamplers to collect E. coli water samples has received little field research attention; thus, this study was implemented to compare refrigerated and unrefrigerated autosamplers and evaluate potential E. coli concentration differences due to field storage temperature (storms with holding times ≤24 h) and due to field storage time and temperature (storms >24 h). Data from 85 runoff events on four diverse watersheds showed that field storage times and temperatures had minor effects on mean and median E. coli concentrations. Graphs and error values did, however, indicate a weak tendency for higher concentrations in the refrigerated samplers, but it is unknown to what extent differing die-off and/or regrowth rates, heterogeneity in concentrations within samples, and laboratory analysis uncertainty contributed to the results. The minimal differences in measured E. coli concentrations cast doubt on the need for utilizing the rigid conventional protocols for field holding time and storage temperature. This is not to say that proper quality assurance and quality control is not important but to emphasize the need to consider the balance between data quality and practical constraints related to logistics, funding, travel time, and autosampler use in storm water studies.  相似文献   
106.
A new large-scale closed chamber fumigation system with cooling facilities is described for studying effects of low concentrations of SO(2), NO(2) and O(3) and low temperatures on woody species and herbaceous plants. The system is based on modified hemispherical greenhouses with a forced air ventilation system. This provides a chamber environment with low spatial variability of pollutant gas concentrations and rapid air circulation which allows exposure of plants at near ambient temperatures and relative humidity. Large capacity cooling units come into operation when ambient temperatures fall below 0 degrees C, and these allow chamber temperatures to be lowered by an additional 4 to 8 degrees C in experiments designed to test whether exposure to pollutants enhances the frost sensitivity of plants.  相似文献   
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Polystyrene (PS) is currently used as packaging, insulating and storing material in various industrial or domestic fields. As a result, a large quantity of PS wastes is produced. Plastic wastes are not usually biodegradable, so it is necessary to suggest a technology to recycle them. Landfills and incineration are reasonably cheap methods but are not environmentally acceptable, therefore, alternative methods for polymer recycling are required. The general purpose of PS foam recycling is to recover a more compact polymeric material without degradation. Dissolution with terpenic solvents is presented here as an efficient and cheap alternative that is developed at room temperature; among the oils studied, limonene was selected because of its intermediate solubility and its abundance. The solvent removal is possible thanks to supercritical technology that provides a high solubility in limonene and almost a complete PS insolubility at moderated pressures (77?bar) and low temperatures (30?°C). Thus, based on the results of thermogravimetric and chromatographic analysis, we propose that.supercritical antisolvent precipitation is an ideal technique for carrying out the separation of PS and limonene, providing a recycled polymer with a reduced volume, almost completely free of solvent and without degradation of the polymeric chains.  相似文献   
110.
The COVID-19 pandemic and related social and economic emergencies induced massive public spending and increased global debt. Economic recovery is now an opportunity to rebuild natural capital alongside financial, physical, social and human capital, for long-term societal benefit. Yet, current decision-making is dominated by economic imperatives and information systems that do not consider society’s dependence on natural capital and the ecosystem services it provides. New international standards for natural capital accounting (NCA) are now available to integrate environmental information into government decision-making. By revealing the effects of policies that influence natural capital, NCA supports identification, implementation and monitoring of Green Recovery pathways, including where environment and economy are most positively interlinked.  相似文献   
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