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Free amino acids in the waters of the English Channel have been measured over a twelve month period using a newly developed field technique. Samples have been taken over a wide area both from the surface and at depth. The results show that the levels of amino acids found in these studies are greater than those previously generally accepted. These findings are of considerable importance in productivity studies since amino nitrogen as a source of nutrient for phytoplankton has been largely neglected. This paper shows that the levels of amino acids in the upper layers of the sea are not insignificant and should not be disregarded as an alternative nitrogen source for phytoplankton. 相似文献
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995.
Claire Freeman 《Journal of Environmental Planning and Management》1996,39(1):65-78
Local Agenda 21, with its major emphasis on local accountability and democratization, challenges perceptions of local governance and offers a long overdue opportunity, for local authorities in particular, to develop broad-based, effective, participatory structures. This paper examines initial responses to this opportunity. It models the newly emerging participatory structures and processes in selected English local authority areas, and demonstrates that there may be no one path that local authorities should follow. A number of alternative approaches to community participation can and are being adopted, contingent upon local circumstances. 相似文献
996.
James G. Teer 《Environmental management》1996,20(6):925-931
Conservation of living resources is no longer parochial in scope; it is a global challenge. Ecological, social, political, and business interests operate in a network that reaches across seas, continents, and nations. Industries, including the electric utility industry, are diversifying in products and expanding into international markets. They soon discover that, while all nations have common goals for their peoples, conservation and environmental issues in less-developed nations have different dimensions and norms than are encountered in Western, affluent societies. In developing countries, survival is more of an issue than quality of life, and burgeoning human numbers have put tremendous pressures on resources including wildlife and its habitats. Human population, urbanization of society, changes in single-species to ecosystem and landscape levels of management, and protectionists and animal rights philosophies are influences with which conservation of resources and the environment must contend. The human condition and conservation efforts are inextricably linked. Examples to demonstrate this fact are given for Project Tiger in India, the jaguar in Latin America, and the Serengeti ecosystem in Kenya and Tanzania. 相似文献
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Fred Luthans James B. Avey Bruce J. Avolio Steven M. Norman Gwendolyn M. Combs 《组织行为杂志》2006,27(3):387-393
After first providing the meaning of psychological capital (PsyCap), we present a micro‐intervention to develop it. Drawn from hope, optimism, efficacy, and resiliency development, this PsyCap Intervention (PCI) is shown to have preliminary support for not only increasing participants' PsyCap, but also financial impact and high return on investment. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
999.
James W. Bryant 《Resources Policy》1981,7(1):39-44
In recent years political instability and economic uncertainty have dominated resources policy issues. As a result, conflicts of interest have arisen in many contexts relating to the control and use of natural resources. A number of methodologies have been developed to study conflict situations in other areas, and this paper seeks to demonstrate the relevance and usefulness of these methodologies in the natural resources field. The resulting models do not always have predictive power but can provide valuable insights into the structure of conflicts. 相似文献
1000.
OBJECTIVES: The present study aimed to investigate the illicit drug use patterns of long-distance truck drivers. This population is considered to be a special interest group in terms of drug-driving research and policy due to high rates of use, involvement of drugs in truck accidents, and the link between drug use and work-related fatigue. METHODS: Qualitative interview data were collected from 35 long-haul truck drivers in Southeast Queensland and analyzed through grounded theory techniques. Interviews were conducted at truck stops and loading facilities in both metropolitan and regional cites throughout Queensland. RESULTS: High rates of licit and illicit drug use (particularly amphetamines) were reported by the majority of the sample. However, unlike previous studies that focus on fatigue, this research found overlapping and changing motivations for drug use during individual lifetimes. Becker's model of a drug use "career" was utilized to reveal that some drivers begin illicit drug use before they commence truck driving. As well as fatigue, powerful motives such as peer pressure, wanting to fit the trucking "image," socialization, relaxation, and addiction were also reported as contributing factors to self-reported drug driving. CONCLUSIONS: The results indicate that these additional social factors may need to be considered and incorporated with fatigue factors when developing effective drug prevention or cessation policies for truck drivers. 相似文献