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581.
This paper focuses on the issues arising from Local Agenda 21 where the role of local authorities is seen as vital in promoting and achieving sustainable development. The implications of the current forms of public sector restructuring for local authorities, and in particular the consequences of the requirement to contract out the delivery and management of traditional environmental services such as grounds maintenance are considered. The paper concludes that the ongoing processes of local government restructuring, together with the removal of many functions from local democratic control, are reducing the capacity of local communities to respond positively to the demands of Local Agenda 21. 相似文献
582.
Alan Richardson 《Journal of Environmental Planning and Management》1985,28(2):60-65
Traditional economic planning policies do not, largely, benefit residents of run‐down inner city neighbourhoods. Planners have therefore begun to look at other ways to improve the economic well‐being of unemployed people in such areas. One such initiative has been the location of Community Employment Development Officers in economically depressed areas by Cleveland County Council — one of Britain's unemployment blackspots. Their remit is to encourage and initiate action to create jobs and this paper looks at the experiment, drawing out some of the lessons. 相似文献
583.
The Delphi approach to the mediation of environmental disputes 总被引:1,自引:1,他引:1
Environmental disputes, in many countries, have taken on a ritualistic character. Their persistence, even after prolonged analysis and debate, suggests that they result from ideological rather than factual differences. Since no single ideological position holds a monopoly on the truth, effective environmental management would seem to require an integration of views, the problem being how to achieve this. One approach to this problem is illustrated in this article. Two factions in the spruce budworm dispute in New Brunswick, Canada, were engaged in a mediation exercise using the Delphi method. Details of the design and execution of this form of mediation are provided, together with an evaluation of the Delphi's effectiveness in this context. 相似文献
584.
Alan Miller 《The Environmentalist》1982,2(3):223-231
Summary This is a paper about problem-solving styles in Environmental Management and the specific deficiencies in these styles that
might be groupd under the label ‘tunnel vision’. The latter, a form of selective attention, contributes to inadequate problem-formulation,
partial solutions to complex problems and to the generation of even more intractable, additional problems. Examples of tunnel
vision in military and environmental decision-making are discussed, together with the situational, personal and educational
factors that exacerbate its influence. The paper concludes with some recommendations for changes in professional education
that might help to recduce the occurrence of tunnel vision.
Dr Alan Miller who is now associate professor at the University of New Brunswick received his training in biology (in England)
and ecology (in Canada). He then spent several years pursuing research at the Northwest Institute for Medical Research in
Chicago, USA. A growing interest in the human aspects of environmental and medical problems led to a further graduate study
in psychology, followed by teaching positions in Ireland and Canada. His current interests include: the education of environmental
professional; the psychosocial problems involved in environmental management, and, the problems inherent in interdisciplinary
project groups. 相似文献
585.
Alan R. Hill 《Journal of the American Water Resources Association》1981,17(4):627-634
: The export of dissolved molybdate reactive phosphorus (DMRP) from 22 watersheds in the Duffin Creek drainage basin near Toronto Ontario was measured over a 25-month period. The annual average loss varied from 0.027 to 2.11 kg P/ha. Phosphorus levels in a number of watersheds were strongly influenced by effluent from a sewage treatment plant which contributed about 68 percent of the annual DMRP input to Duffin Creek. An analysis of 12 watersheds which did not contain major point pollution sources revealed that DMRP concentration and losses had a significant positive correlation with crop area and a strong negative association with forest, abandoned farm land, and area of sand + sandy loam soils. The causal relationships underlying these simple correlations are difficult to evaluate because of considerable multicollinearity between land use, soil, and topographic variables. Analysis of a mass balance for the downstream reaches of Duffin Creek indicated that there was considerable retention of phosphorus in the river channel particularly during summer low flows. 相似文献
586.
Recovery of lotic periphyton communities after disturbance 总被引:2,自引:0,他引:2
Periphyton communities represent potentially excellent candidates for assessing the recovery of lotic ecosystems after disturbance.
These communities are ubiquitous, relatively easy to sample and measure (in terms of total community biomass), have short
generation times, and may influence the recovery rates of higher trophic levels. The first section of this article analyzes
how site availability, species availability, and differential species performance influence periphyton successional dynamics.
This background information provides a foundation for understanding how periphytic organisms respond after a disturbance.
The second section of this article analyzes how periphyton communities respond to four different types of disturbance (flood
events, desiccation, organic nutrient enrichment, and toxic metal exposure). Although data are limited, it is concluded that
the fast growth rates and short generation times of periphytic organisms, coupled with their flexible life history strategies
and good dispersal ability, allow lotic periphyton communities to recover relatively quickly after a disturbance. In addition,
disturbance type and severity, local environmental conditions, and site-specific factors also will influence recovery rates.
Future research needs include a better understanding of: (1) what periphyton property(ies) would serve as the best index of
recovery; (2) whether or not the robustness of this index varies among different environments and different disturbances;
(3) interactions between autotrophs and heterotrophs within the periphyton mat, particularly with respect to nutrient cycling;
(4) competitive interactions among organisms; (5) functional redundancy of organisms; and (6) the influence of the riparian
zone and channel geomorphology on periphyton recovery rates. 相似文献
587.
Alan Ewert 《Environmental management》1990,14(2):179-184
Mount St. Helens provides an interesting case study of a forest and wildland area that has been radically altered in recent
history. As a result of volcanic activity, the recreation environment has changed with respect to the setting, climbing opportunities,
and motivations for mountaineering. An evaluation process using both qualitative and quantitative methods was developed to
determine what the motivations, demographic characteristics, and preferred management techniques were for the posteruption
Mount St. Helens mountain-climbing visitor. Results suggest that changes have occurred in the “new” or posteruption climbing
visitor. These changes have not all been congruent with those anticipated by management. For example, the climbing visitor
is now less interested in climbing opportunities and more concerned with seeing the crater and other volcanic-related features.
This article discusses the findings of this research in light of how resource managers might consider the issue of visitor
changes in both demands and types of uses. For example, determining quota numbers based on sociological determinants (e.g.,
desire for solitude) need to be firmly grounded in who the visitors actually are rather than who they were. Consequently,
management tools such as the Recreational Opportunity Spectrum (ROS) and Limits of Acceptable Change (LAC) may need to be
altered to accommodate a changing resource or visitor base. These and other findings have implications for the future management
practices of the Mount St. Helens area and other environments where the recreation resources have undergone rapid and profound
change. 相似文献
588.
Brendan G. Mackey Henry A. Nix Michael F. Hutchinson June P. Macmahon P. Michael Fleming 《Environmental management》1988,12(4):501-514
Problems arising from application of the representative criterion for conservation and natural heritage evaluation are discussed. An ecological basis to this criterion is suggested that focuses on those key environmental factors dominating biotic response. A methodology is proposed that utilizes computer-based methods of establishing and interrogating spatial data bases (geographic information systems), environmental modeling, and numeric analysis. An example is presented illustrating some of the advantages and limitations of classification and dimension reduction techniques in both defining bioenvironments and displaying their spatial distribution. The advantages of this method for representativeness evaluation are that it maximizes the utility of available data, is explicit and repeatable, and enables large areas to be analyzed at relatively fine scales. 相似文献
589.
Snow was used as a collection medium to examine 1,3,5-hexahydro-1,3,5-trinitrotriazine (RDX) and 2,4,6-trinitrotoluene (TNT) residues post-detonation of 60-, 81-, and 120-mm mortar rounds, 105- and 155-mm howitzer rounds, M67 hand grenades, 40-mm rifle grenades, and blocks of C4. Residue-covered snow samples were collected, processed, and analyzed for explosives without cross-contamination from previous detonations and other potential matrix interferences. Detonation trials were performed following standard military live-fire and blow-in-place techniques. When possible, replicate munitions were detonated under similar conditions to provide a more reliable estimation of the mass of unconsumed high explosive residues. Overall the amount of energetic residues deposited from live-fire detonations were considerably less than the energetic residues deposited by blow-in-place detonations. 相似文献
590.
The quantification and distribution of pollution Pb at a woodland in rural south central Ontario, Canada 总被引:1,自引:0,他引:1
Lead concentrations and Pb isotope ratios were measured in the forest floor, mineral soil and vegetation at a white pine and a sugar maple stand in a woodland in south central Ontario. Lead concentrations decreased and 206Pb/207Pb ratios increased with mineral soil depth reflecting the mixing of pollution and natural Pb sources. Lead concentrations and 206Pb/207Pb ratios at 20-30 cm depth were approximately 6-7 mg/kg and 1.31-1.32, respectively. Assuming an integrated 206Pb/207Pb ratio in deposition over time of 1.18, estimated from lichen measurements and published data for the region, approximately 65% of Pb in the surface (0-1 cm) mineral soil is from anthropogenic sources. Approximately 90% of pollution Pb is found in the 0-10 cm soil layer (Ah) and less than 3% of the pollution Pb is present in the forest biomass and mull-type forest floor combined. Despite low Pb concentrations in vegetation (<2.5 mg/kg), we estimate that between 65 and 100% of the Pb in vegetation and approximately 75% of the Pb in the forest floor is from pollution sources. In total, the pollution Pb burdens at the pine and maple stands are estimated to be 860 and 750 mg/m2, respectively. 相似文献