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31.
Bonzongo JC  Lyons WB 《Ambio》2004,33(6):328-333
Mercury (Hg) concentrations above levels that could pose health risks have been measured recently in predatory fish from many aquatic systems in the southeastern region of the United States. Based on hypotheses derived from published experimental data on the aqueous geochemistry of Hg, we investigated the effect of certain natural and human-imposed conditions on in situ levels of methylmercury (MeHg) in the Mobile-Alabama River System (MARS). Water samples were collected from different types of environments, hypothesized to have contrasting levels of MeHg in the aqueous phase, and were analyzed for total-Hg (THg) and MeHg concentrations, as well as some key geochemical parameters. The results showed the following. i) Overall, total Hg concentrations in waters of the MARS are quite uniformly distributed and vary from 0.2 to 6 ng L(-1), suggesting that besides geological sources, atmospheric deposition is certainly the main source of Hg inputs in the studied system. ii) In locations with comparable THg levels, the Hg fraction present as MeHg was consistently higher in samples collected from the Coastal Plain portion of the MARS as compared to those from other geological provinces. iii) Our in situ observations confirmed conclusions derived from laboratory experiments, in that, MeHg abundance in aquatic systems correlates with sulfate (but only within a narrow range of concentrations); decreasing pH; and has no direct relationships with either nitrate or phosphate. iv) The investigation of Hg accumulation in biota at a single site showed that an aquatic system with low THg concentrations but a high MeHg:THg ratios, could have organisms with Hg content above safe levels. Therefore, potential health risks to fish eating populations can exist even when the aqueous phase does not show signs of significant Hg enrichment.  相似文献   
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The new ACE2 (Altimeter Corrected Elevations 2) Global Digital Elevation Model (GDEM) which has recently been released aims to provide the most accurate GDEM to date. ACE2 was created by synergistically merging the SRTM and altimetry datasets. The comprehensive comparison carried out between the two datasets yielded a myriad of information, with the areas of disagreement providing as much valuable information as the areas of agreement. Analysis of the comparison dataset revealed that certain topographic features displayed consistent differences between the two datasets. The largest differences globally are present over the rainforests, particularly the two largest, around the Amazon and the Congo. The differences range between 10 m and 40 m; these differences can be attributed to the height of the rainforest canopy, as the SRTM returned height values from somewhere within the uppermost reaches of the vegetation whereas the altimeter was able to penetrate through and return true ground heights. The second major class of terrain feature to demonstrate coherent differences are desert regions; here, different deserts present different characteristics. The final area of interest is that of Wetlands; these are areas of special significance because even a slight misrepresentation of the heights can have wide ranging effects in modelling wetland areas. These examples illustrate the valuable additional information content gleaned from the synergistic global combination of the two datasets.  相似文献   
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A denitrifying bacterium was isolated from activated sludge after enrichment on 4‐chlorophenol under anoxic, denitrifying conditions, and the microbial degradation of 4‐chlorophenol by this bacterium, with nitrate as the only electron acceptor, was investigated. The bacterium was capable of degrading up to 5 mM 4‐chlorophenol with stoichiometric release of chloride under denitrifying conditions. Anaerobic degradation of 4‐chlorophenol was dependent on nitrate as an electron acceptor. Nitrate (10 mM) severely inhibited the growth by the toxic effect of the accumulated nitrite. The optimum nitrate concentration for cell growth and chlorophenol degradation was 6 mM.  相似文献   
36.
Monkey alarm calls have shown that in the primate clade, combinatorial rules in acoustic communication are not exclusive to humans. A recent hypothesis suggests that the number of different call combinations in monkeys increases with increased number of predator species. However, the existence of combinatorial rules in great ape alarm calls remains largely unstudied, despite its obvious relevance to ideas about the evolution of human speech. In this paper, we examine the potential use of combinatorial rules in the alarm calls of the only Asian great ape: the orangutan. Alarm calls in orangutans are composed of syllables (with either one or two distinct elements), which in turn are organized into sequences. Tigers and clouded leopards are predators for Sumatran orangutans, but in Borneo, tigers are extinct. Thus, orangutans make a suitable great ape model to assess alarm call composition in relation to the size of the predator guild. We exposed orangutans on both islands to a tiger and control model. Response compositionality was analyzed at two levels (i.e., syllable and syllable sequences) between models and populations. Results were corroborated using information theory algorithms. We made specific, directed predictions for the variation expected if orangutans used combinatorial rules. None of these predictions were met, indicating that monkey alarm call combinatorial rules do not have direct homologues in orangutans. If these results are replicated in other great apes, this indicates that predation did not drive selection towards ever more combinatorial rules in the human lineage.  相似文献   
37.
Multinational corporations are facing increasing pressures and finding stronger incentives to integrate environmental management into their overall business strategies. National and local environmental regulations are becoming more stringent in Europe, Japan, East and Southeast Asia, Latin America, and many developing countries, and international voluntary standards of environmental management are being endorsed by a growing number of governments. Multinational firms are embracing these standards not only to assure the public of their concern for environmental protection, but also to enhance their competitiveness in international markets. The British Standard 7750, the European Eco-Management and Audit Scheme (EMAS), and the ISO 14000 series are setting new guidelines for effective corporate environmental management. Beyond complying with local and national laws, corporations now have wider latitude in how they adapt their business practices to these emerging environmental management standards. In order to capitalize on that creative latitude, companies must have corporate cultures and internal management systems that allow them to respond quickly and effectively to changing environmental requirements. Exemplary corporate environmental performance is usually related to strong and progressive leadership, a culture that recognizes the importance of environmental protection, and the willingness to operate by quality-based management principles. This article describes how one international corporation, Sonoco, in responding successfully to changing environmental pressures to reclaim and recycle its products in the wake of the solid waste crisis in the United States and more stringent environmental regulations in Europe, used its management competencies and corporate culture to turn what could have been serious barriers to expansion of its core businesses into new opportunities. By adopting a bold materials reclamation program, Sonoco was able to overcome potential limitations on its operations in the United States and abroad and to develop new business segments that benefited the company and the environment.  相似文献   
38.
More than 200 years ago, Adam Smith, the founder of modern economics, wrote in the Wealth of Nations that “…consumption is the sole end and purpose of all production; and the interest of the producer ought to be attention to…that of the consumer.” In recent years, the rapid growth of the world economy has given Adam Smith's maxim new meaning. The age-old desire for consumption grows unabated and increasing numbers of consumers around the world are attaching new value to the environmental quality of goods and services and expressing concern over the environmental impacts of industrialization. That concern is growing because more than 70 percent of the world's urban population live in areas where the air is seriously polluted and as many as 750,000 people—the majority in developing countries—die each year of ailments caused by air pollution.1 Over the past 25 years, corporations throughout the world have made dramatic changes in the way they do business as more people come to understand how the ecological system works and how polluted air and water endanger human health. The key to increasing industry's participation in the drive for higher standards of air quality is the growing realization that effective environmental management, technological development, and technology dissemination are cost-effective and profitable business strategies. Global competition is making firms around the world more customer-conscious and, to the extent that consumers demand products that minimize environmental degradation and enhance the quality of their lives, businesses in every industry must respond in order to survive.2 This article examines how changes in business practices, driven by a better understanding of how natural environments function, are converging to provide new opportunities for environmental management that go beyond regulatory compliance to reduce air pollution. Although sound and well-enforced environmental regulations are an essential foundation for improving air quality, command-and-control systems alone are unlikely to achieve the lower levels of pollution that will be necessary to achieve sustainable development in the 21st century. In cooperation with government, businesses in every industry can play crucial roles in achieving higher standards of air quality while at the same time maintaining acceptable levels of economic growth. We explore three ways in which corporations can contribute to environmentally sustainable development: (1) by adopting proactive environmental management systems that focus on air pollution prevention; (2) by developing new technologies for air pollution control and reduction; and (3) by transferring air pollution control and prevention technologies through international trade and investment.  相似文献   
39.
Outreach nurseries are favored conservation and social forestry tools globally, but, as with many integrated conservation and development programs (ICDPs), they do not always produce anticipated results. A synopsis of the experience of South African practitioners is provided in this study of 65 outreach nurseries. South African outreach nurseries frequently include financial objectives, creating additional challenges in simultaneously attaining conservation and socioeconomic goals. Progress was hindered by biophysical problems (e.g., lack of water, poor soils, etc.) as well as the harsh socioeconomic conditions facing most communities in which nurseries had been established. Attaining financial viability was challenging. Business management skills were often restricted, and few viability studies included adequate market research. Costs to community participants were usually high, and benefits were limited. Conservation objectives were frequently lost in the struggle to attain financial viability. The management of social processes also proved challenging. Although small scale and relatively straightforward compared with many ICDPs, nurseries usually require substantial institutional support, including a range of technical, business, and development services. Project time frames need to be reconsidered, as practitioners estimate that it takes 5–10 years for nurseries to start meeting objectives, and donors and implementing agencies often operate on 2–3-year project cycles. Detailed viability studies are essential, incorporating a social probe and an assessment of potential impacts of projects on community participants. Progress needs to be continuously evaluated to enable institutions and community participants to adapt to changing conditions as well as ensure that the spectrum of objectives are being achieved.  相似文献   
40.
Developing a globally responsive Science‐Practitioner‐Humanist model (Lefkowitz, 2008 ) means articulating professional values (supply) and meeting global demand. The United Nations' Millennium Development Goals (MDGs) seek to halve human poverty by 2015 and how organizations respond to this constitutes a formidable demand on Organizational Psychology. A key process for delivering more effective aid is the Paris Declaration on Aid Effectiveness, which seeks collaborative contributions from a plethora of Organizations, including business organizations and professions like ours. We argue that a thoughtful articulation of what Organizational Psychology uniquely stands for, and can offer, is therefore needed. It is proposed that a key mechanism for addressing this challenge is a Task Force, whose functions will include the coordination of institutions within psychology, and linking them to those in development. We describe such a task force and outline its core mission (Reichman, Frese, Schein, Carr, MacLachlan, & Landy, 2008 ). Organizational Psychology's response to poverty reduction should meet Lefkowitz's criteria for developing a more humanist model of science and practice as the MDGs are inherently humanist and values‐based. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
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