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1.
Arsenic levels in seawater, microplankton (diatoms and dinoflagellates), shrimp (Penaeus semisulcatus), mollusc (Cerithium scabridum) and five types of fish (Maid, Nakroor, Nuwaiby, Suboor and Sheim) in five sampling stations (I–V) off the Kuwait coast were determined during the years 1995 to 1999. The maximum mean concentration of arsenic was observed in the order; the five fish (0.50–0.78 g g–1)> mollusc (0.26 g g–1)> shrimp (0.23 g g–1)> particulate matter (0.03 g g–1)> water and phytoplankton (0.02 g g–1) from all the sites of the Kuwait coast. Station II possessed the maximum arsenic levels. In comparison with the arsenic levels in other parts of the globe, low arsenic levels were observed in most of the marine organisms off the Kuwait Coast. However, an increasing trend in arsenic concentrations was anticipated due to rapid local industrialization and on account of recent spills of arsenic compounds.  相似文献   

2.
Summary Effective communication concerning environmental issues can take a variety of forms. The following essay is offered as a metalogue, a piece of writing in which the writing itself illustrates the principles developed in the writing.International readers will be helped if they know that Jack Armstrong and Sergeant Preston are heroes of moralizing (and often jingoistic) radio dramas popular among children in the United States during the War years and that the Tom Mix Holster Set and the A-bomb Ring were premiums offered to children in boxes of cold cereal in the period after the War. These trivia illustrate the kinds of societal messages directed toward the generation of Americans who presumably will be running the country during the 1980s.The authors are a professor of Psychology and Ethology and a graduate student in International Development. Both attended Harvard University in the late 1950s and the University of California, Berkeley, in the early 1960s. Their autobiographical reflections have something to say about the motivation underlying the environmental movement and where these motivations are likely to lead in the near future.  相似文献   

3.
Professor Kathryn George's Use and Abuse Revisited does not contain an accurate assessment of my On Vegetarianism, Morality, and Science: A Counter Reply. I show that she has misrepresented my moral and empirical argumentation.  相似文献   

4.
The United States Forest Service is required to analyze road systems on each of the national forests for potential environmental impacts. We have developed a novel and inexpensive way to do this using the Ecosystem Management Decision Support program (EMDS). We used EMDS to integrate a user-developed fuzzy logic knowledge base with a grid-based geographic information system to evaluate the degree of truth for assertions about a roads environmental impact. Using spatial data for natural and human processes in the Tahoc National Forest (TNF, California, USA), we evaluated the assertion the road has a high potential for impacting the environment. We found a high level of agreement between the products of this evaluation and ground observations of a TNF transportation engineer, as well as occurrences of road failures. We used the modeled potential environmental impact to negatively weight roads for a least-cost path network analysis to 1573 points of interest in the forest. The network analysis showed that out of 8233 km of road analyzed in the forest, 3483 km (42%) must be kept in a modified road network to ensure access to these points. We found that the modified network had improved patch characteristics, such as significantly fewer cherry stem roads intruding into patches, an improved area-weighted mean shape index, and larger mean patch sizes, as compared to the original network. This analysis system could be used by any public agency to analyze infrastructure for environmental or other risk and included in other mandated analyses such as risks to watersheds.  相似文献   

5.
This study compares community-based managed forests under different purposes of management, namely, state-driven conservation or community-designed utilization in two villages located in the Sopsai watershed, Nan Province, northern Thailand. The forest health under different intensity of uses is assessed in association with the collective behaviors and long-term purposes embedded in village social–cultural context. The study found no significant differences in forest succession and proportion in diameter at 1.3 m (dbh) class and height-class distribution of the forest under different use intensity. The forest for utilization also showed higher density and basal area of the local preferred species than the conservation forest. In the utilization forest, we also found a higher number of multipurpose and preferred species than in the conservation forest, which actually responded to the needs of the community in the long term to have more wood products (both firewood and timbers). The community-based forest management (CBFM) for utilization can also lead to natural regeneration and biodiversity similar to conservation forests. Through CBFM, forest resources can be managed to maintain the healthy condition under different intensities and respond to both community needs and external expectation. The findings also emphasize the importance of recognizing community needs and management objectives in watershed restoration and improving the productivity of forests under collective management.  相似文献   

6.
Wetlands, like any other environmentally sensitive resource, require very careful evaluation. While it is accepted that all wetlands may be equally valuable in terms of maintaining global life-support systems, individual areas may be ranked according to their uniqueness or the irreplaceability of the resource should the wetland be developed. The various techniques available for evaluating the wetland resource in the development versus conservation conflict situation are critically assessed. Indirect appraisal via the opportunity cost method can generate valuable data which have contributed to the mitigation of such conflict situations.The Broadland, in Norfolk, England, recently designated an environmentally sensitive area (ESA), provides a case study example of wetland management. The search for an acceptable flood alleviation strategy for the ESA is examined in detail. The economic and environmental asset structure of the study area is examined at two levels. A basic screening system is applied to each of the identified flood protection planning units to enable the rank ordering of the units. A more detailed appraisal is then made of the value of selected units so that the cost-effectiveness of any planned expenditure on flood protection works can be assessed. Specific management issues and their likely effect on the environment, in terms of land use for example, are also addressed. The 1986 Agriculture Act marks a potential watershed in British conservation policy. The ESA policy encompasses a dual management strategy that attempts to stimulate compatible agricultural and conservation practices and activities. Other countries that still retain significant unspoiled wetland resources may find that preemptive regulatory government intervention in favor of conservation would help to avoid the worst aspects of the British experience.  相似文献   

7.
This article considers the dispute between moral economy and rational peasant theories of agrarian societies in application to problems of collective action. The moral-economy theory holds that traditional peasant society is organized cooperatively through shared moral values and communal institutions; while the rational-peasant theory maintains that peasant society shows the mark of rational individual calculation, leading to free-rider problems that undermine successful collective action. This article offers an abstract model of a traditional village and assesses the applicability of recent qualifications of the collective action argument to this model. It will emerge that the social characteristics of the traditional village embody features that facilitate collective action by rational peasants.  相似文献   

8.
US civil defense planning for nuclear attack since 1974 has emphasized the doctrine of crisis relocation. Under this doctrine, some 150 million people would evacuate from urban areas and other probable targets to rural host communities. The population of the latter would stay put to assist the relocatees. Local communities would be responsible for the welfare of up to ten times their normal population for an indefinite period of time.This study examined certain implications of crisis relocation for the town of Greenfield, Massachusetts, USA, a typical host community. Various assumptions were articulated regarding the timing of events, the season of year, weather, and social behavior. Assumptions were favorable to the success of crisis relocation. Nevertheless, Greenfield would face impossible burdens in attempting to provide fallout protection, water, food, medical care, and civil order. Additional pressures would arise from adjoining communities which are functionally dependent upon Greenfield for normal goods and services, but which would receive their own allotment of relocatees. Crisis relocation is not taken seriously in Greenfield and virtually no preparations have been made to implement it.  相似文献   

9.
This article examines the likely impacts of the United States' new federalism on natural hazard land use management in Colorado. Flood and avalanche hazard programs are the focus of the study Both short- and long-term effects of changes in funding are discussed, and the conclusions summarize probable positive and negative program impacts for the state. These results may help researchers and state authorities mitigate similar effects in their states prior to the enactment of new federalism.  相似文献   

10.
A cooperative mangrove mapping project between the Ecuadorian Center for Remote Sensing (CLIRSEN) and the University of Delaware was begun in August 1982. The objectives of the project were to create historical maps of mangrove ecosystem extent and change, while transferring aerial photographic interpretation techniques to Ecuadorian personnel. The result of this cooperation was a series of three 125,000 scale maps of historical mangrove extent and change from 1966 to 1982 in the southern Gulf of Guayaquil. This multitemporal study showed a 16% decrease in mangrove extent and a 27% increase in shrimp pond development. If these rates of change prevail into the future, mangroves in Ecuador will reach parity with shrimp ponds in 1984 and completely disappear by mid-1990. Recognizing the significance of this loss to shellfish and fish production along the coast, Ecuadorian scientists at CLIRSEN have subsequently initiated a nationwide mangrove mapping program to create a historical base for future mangrove management strategies.  相似文献   

11.
Floodplain forests are flood-dependent ecosystems. They rely on well-timed, periodic floods for the provision of regeneration sites and on tapered flood recession curves for the successful establishment of seedlings. These overbank flood events are described as regeneration flows. Once floodplain forest trees are established, in order to grow they also require adequate, although variable, river stage levels or maintenance flows throughout the year. Regeneration flows are often synonymous with flood flows and only occur periodically. There is a disparity between this need for varied interannual flows over the decadal time frame and the usual annual cycle of flow management currently used by most river management agencies. Maintenance flows are often closer to established minimum flows and much easier to provide by current operational practices.A number of environmental flow methodologies, developed in North America, Australia, and South Africa are described in this review. They include the needs of the floodplain environment in the management and allocation of river flows. In North America, these methodologies have been put into practice in a number of river basins specifically to restore floodplain forest ecosystems. In Australia and South Africa, a series of related holistic approaches have been developed that include the needs of floodplain ecosystems as well as in-channel ecosystems. In most European countries, restoration of floodplain forests takes place at a few localized restoration sites, more often as part of a flood-defense scheme and usually not coordinated with flow allocation decisions throughout the river basin. The potential to apply existing environmental flow methodologies to the management of European floodplain forests is discussed.  相似文献   

12.
The case against free market environmentalism   总被引:2,自引:1,他引:1  
Free market environmentalists believe that the extension of private property rights and market transactions is sufficient to address environmental difficulties. But there is no invisible hand operating in markets that ensures that environmentally sound practices will be employed just because property rights are in private hands. Also, liability laws and the court systems cannot be relied upon to force polluters to internalize the social costs of pollution. Third, market prices do not provide an objective measure of environmental matters. Finally, there is a right to a livable environment that justifies regulations protecting the public from unreasonable environmental risks.  相似文献   

13.
Soil loss and surface runoff patterns over a four-year period (1997–2000) were studied in erosion plots from three hillslopes under different vegetative covers (Rosmarinus officinalis, Triticum aestivum and natural-spontaneous vegetation) in Lanjaron (Alpujarras) on the south flank of the Sierra Nevada of southeast Spain. The erosion plots were located on the hillslopes at 35.5% incline, at 1,480 m in altitude and with 41.8 m2 (21 m×1.9 m) in area. The vegetative covers were tested for effectiveness in controlling the surface runoff and soil loss production. The highest runoff and erosion values, ranging from 114.1 to 1.7 mmyr–1 and from 14,564.3 to 6.6 kgha–1yr–1, respectively, over the entire study period, were measured under the Triticum aestivum. In the Rosmarinus officinalis, runoff ranged from 7.9 to 1.3 mmyr–1 and erosion from 156.4 to 2.3 kgha–1yr–1, while on the hillslope under natural-spontaneous vegetation, runoff ranged from 4.4 to 0.9 mmyr–1 and erosion from 322.3 to 2.2 kgha–1yr–1. According to the results the vegetative covers of Rosmarinus officinalis and natural-spontaneous vegetation reduced the soil losses by 99 and 98%, with respect to the Triticum aestivum, and the runoff losses by 94 and 96%, respectively. Also, the Rosmarinus officinalis and natural-spontaneous plants influenced infiltration by intercepting much of the rainfall water respect to the Triticum aestivum. Monitoring allowed more direct linkages to be made between management practices and their impacts on runoff and soil erosion, thereby enabling to identify problems and take appropriate preventive measures to improve the management practices.  相似文献   

14.
Nature quality in relation to farming is a complex field. It involves different traditions and interests, different views of what nature is, and different ways of valuing nature. Furthermore there is a general lack of empirical data on many aspects of nature quality in the farmed landscape. In this paper we discuss nature quality from the perspective of organic farming, which has its own values and goals in relation to nature – the Ecologist View of Nature. This is in contrast to the Culturist View characteristic of much conventional agriculture and the Naturalist View characteristic of the traditional biological approach to nature quality. This threefold distinction forms a framework for exploration of nature quality criteria in the farmed landscape. The traditional work on nature quality has mainly focused on biological interests based on a Naturalist View of Nature. In this paper we will explore how criteria for nature quality based on the Ecologist View can be developed and thereby feed into the ongoing discussion of the development of the organic farming practices. We suggest additional criteria for nature quality based on an Ecologist View of Nature: biodiversity, habitat diversity, extent and structure, functional integrity of habitats and agro-ecosystems, landscape integrity, accessibility, and experientiality. The larger set of Naturalist and Ecologist criteria can provide a wider and more balanced basis for developing nature quality indicators that are relevant in the farmed landscapes. This broader approach to nature quality is also expected to benefit the general societal discussions and decisions on farming and nature.  相似文献   

15.
Two hundred and fifty-seven urine samples collected from school children living in the Manzini region, Swaziland, were analysed for lead (Pb), using a graphite furnace atomic absorption spectrometer. The mean urine lead concentration for the urban schools ranged from 0.038–0.040 gml–1, while that for the rural schools ranged from 0.017–0.022 gml–1. The observed range shown by the urban schools was above the normal (for healthy humans) urine lead concentration of 0.035 gml–1. However, the mean urine lead concentration for the rural schools was found to be lower than this value. The mean urine lead concentration for the urban schools was significantly higher than that of the rural schools. The differences in the mean urine lead concentrations for boys and girls from both urban and rural schools were found not to be significant, despite the higher values shown by the girls. The difference in lead concentrations between urban and rural schools in Manzini was thought to be due to the traffic density within the urban area.  相似文献   

16.
Summary Since the late 1960s concern about the pollution of our physical environment has grown into a social and political issue. In this process of increasing awareness, environmental activists have played a catalysing role in most Western countries. Moreover the environmentalists formulated an alternative set of ideas and strategies concerning the production and use of knowledge. These new knowledge interests were organised around three dimensions: cosmology, technology, and the organisation of knowledge production. On the basis of a case-study of Dutch environmentalism this paper tries to demonstrate how the articulation of these new knowledge interests of international scope actually occurred in the particular Dutch national setting. The analysis shows that many of the ideas brought forward in the course of time by Dutch environmentalists have been imported from abroad, especially from the United States, Great Britain and West Germany. However, the specific ways in which Dutch environmentalists have defined the content of their own knowledge interests have depended very much on the particularities of the political culture and socio-economic climate of the Netherlands, as well as the internal dynamics within the various environmental groups themselves.Dr Jacqueline Cramer was until very recently a member of staff in the Department of Science Dynamics at the University of Amsterdam. She has now moved to the TNO Centre for Technology and Policy Studies, P.O. Box 541, 7300 AM, Apeldoorn, The Netherlands. This paper forms part of a comparative study of the development of environmentalism in Sweden, Denmark and the Netherlands carried out in association with Ron Eyerman and Andrew Jamison of the University of Lund, Sweden.)  相似文献   

17.
Summary This technical paper summarizes the various systems currently available for the removal of SOx, NOx and particles from possible acid rain emission sources associated with industrial processes. Preferred systems are outlined in the conclusions.This paper was first presented at the Institution of Environmental Sciences Seminar An Update on Acid Rain which took place in London during November, 1984. Stanley Wallin is a Principal Scientific Officer at Warren Spring Laboratory. He is an engineer working in the environmental field, and his main interests and research are in the measurement and control of pollution from stationary sources. He acts as a consultant for the European Economic Community, the Environmental Protection Agency, and the UK's Health and Safety Executive.  相似文献   

18.
Summary This largely philosophical article argues that we need to examine the roots of our cultural worldview if we are to understand the causes of our global crises and current obstacles to desirable change. Calls for a new ethic are likely to be ineffectual in the absence of a challenge to the damaging dichotomy between fact and value that characterises our culture. However, the dominant worldview is under increasingly strong challege from organic systems thinking which has far-reaching implications, and which suggests that Western culture's dominant assumptions are not in accord with reality. If our culture, and individuals in it, are able to become more balanced, decisive desirable change could take place in society. This balance will involve the proper reintegration of ethical dimensions into thinking, based upon the recognition of the importance of the integrity of human communities and natural systems. This constitutes an emergent worldview and coherent philsophical framework to which many groups are already giving expression. It is imperative that this cultural change is understood and supported as it represents genuine hope for the future.After a teaching career in England and Canada, Stephen Sterling joined, as Assistant Director, the United Kingdom Council for Environmental Education (CEE). He was involved in writing the Education Report forThe Conservation and Development Programme for the UK, and has acted in an advisory capacity on a number of national and international documents on environmental education and environmental ethics. He has edited the CEE's journalReview of Environmental Education Developments for six years. The views expressed in this article are his own.  相似文献   

19.
The conference entitled Managing for Biodiversity: Emerging Ideas for the Electric Utility Industry was held in Williamsburg, Virginia, USA, during 19–20 March 1996. This paper provides an overview of the key points, conclusions, and recommendations from both the presentations/papers and the discussions throughout the conference.  相似文献   

20.
Summary Biosphere II is a new project to build a self-contained ecological system containing humans, plants, and as many other living organisms as necessary for long-term sustenance. Soviet space scientists have already designed Bios 3, simulating conditions on board a flight to Mars. In building Biosphere II, the Institute of Ecotechnics (IE), in collaboration with Space Biospheres Ventures, Decisions Teams Limited, The Environmental Research Laboratory associated with The University of Arizona, and Sarbid Limited, plan to build the prototype of an artificial world in which environmental and ecological processes can be observed closely; An educational, scientific, and ethical laboratory, Biosphere II will raise public consciousness of the interdependence of all life. It will also serve as a control world where possibly harmful environmental effects can be modelled before they reach a crisis stage. Eventually the biospheres are to be marketed and set up in space as the biosphere, no longer in conflict with but aided by human technology, puts forth its young upon other celestial bodies.Dorion Sagan's most recent books areMicrocosmos andOrigins of Sex, both co-authored with Lynn Margulis. He is working onBiospheres, a book on closed ecological systems which is to be published shortly.  相似文献   

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