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31.
Lake Erie water quality has improved dramatically since the degraded conditions of the 1960s. Additional gains could be made,
but at the expense of further investment and reductions in fishery productivity. In facing such cross-jurisdictional issues,
natural resource managers in Canada and the United States must grapple with conflicting objectives and important uncertainties,
while considering the priorities of the public that live in the basin. The techniques and tools of decision analysis have
been used successfully to deal with such decision problems in a range of environmental settings, but infrequently in the Great
Lakes. The objective of this paper is to illustrate how such techniques might be brought to bear on an important, real decision
currently facing Lake Erie resource managers and stakeholders: the choice of new phosphorus loading targets for the lake.
The heart of our approach is a systematic elicitation of stakeholder preferences and an investigation of the degree to which
different phosphorus-loading policies might satisfy ecosystem objectives. Results show that there are potential benefits to
changing the historical policy of reducing phosphorus loads in Lake Erie. 相似文献
32.
M. L. Cocks L. Bangay K. F. Wiersum A. P. Dold 《Environment, Development and Sustainability》2006,8(4):519-533
There is a growing wealth of data capturing the direct-use values of the environment and recognition of forests and wild resources as representing “the poor manȁ9s overcoat”. This focus has however resulted in an emphasis on the utilitarian values of wild resources for rural livelihoods and has for the most part overlooked their cultural values. In tangent to these developments within the field of anthropology there has been increased attention directed towards the relationship between biodiversity and human diversity over the past decade. This has resulted in the recognition of what the Declaration of Belem calls an ȁ8inextricable linkȁ9 between biological and cultural diversity. The term bio-cultural diversity has been introduced as a concept denoting this link. Consequently there is a need for more elaborate assessments of the various ways in which different groups of people find value in biodiversity. The aim of this paper is to demonstrate the cultural significance of wild harvested plant resources for the maintenance of two gender specific cultural artefacts for amaXhosa people in South Africa, to assess the persistence of these practices in rapidly modernizing communities. We demonstrate the endurance of these ancient cultural artefacts in present-day peri-urban communities and suggest that they point to the need for improved understanding of the significance of bio-cultural diversity. The findings of the study should not be interpreted as illustrating stagnation in the traditional past, but rather as pointing at the need for improved understanding of the significance of bio-cultural diversity in a dynamic sense. 相似文献
33.
Selecting Socio-Economic Metrics for Watershed Management 总被引:1,自引:0,他引:1
The selection of social and economic metrics to document baseline conditions and analyze the dynamic relationships between
ecosystems and human communities are important decisions for scientists, managers, and watershed citizens. A large variety
of social and economic data is available but these have limited use without theoretical frameworks. In this paper, several
frameworks for reviewing social-ecosystem relations are offered, namely social sanctions, sense of place, civic structure,
and cultural differences. Underlying all of these frameworks are attitudes, beliefs, values, and norms that affect which questions
are asked and which indicators are chosen. Much work and significant challenges remain in developing a standard set of spatially
based socio-economic metrics for watershed management. 相似文献
34.
孟华 《防灾科技学院学报》2004,6(4):60-64
中央电视台1994年推出的《焦点访谈》栏目开创了我国电视新闻评论发展的新路子,并很快成为受众一致认可的名牌节目。在新闻评论课教学中,分析《焦点访谈》栏目的特点,总结栏目成功经验,对于学生更好地理解电视新闻评论很有必要。 相似文献
35.
Narayan Yoganandan Mike W.J. Arun Frank A. Pintar Anjishnu Banerjee 《Traffic injury prevention》2015,16(4):S100-S107
Objective: Derive lower leg injury risk functions using survival analysis and determine injury reference values (IRV) applicable to human mid-size male and small-size female anthropometries by conducting a meta-analysis of experimental data from different studies under axial impact loading to the foot–ankle–leg complex.Methods: Specimen-specific dynamic peak force, age, total body mass, and injury data were obtained from tests conducted by applying the external load to the dorsal surface of the foot of postmortem human subject (PMHS) foot–ankle–leg preparations. Calcaneus and/or tibia injuries, alone or in combination and with/without involvement of adjacent articular complexes, were included in the injury group. Injury and noninjury tests were included. Maximum axial loads recorded by a load cell attached to the proximal end of the preparation were used. Data were analyzed by treating force as the primary variable. Age was considered as the covariate. Data were censored based on the number of tests conducted on each specimen and whether it remained intact or sustained injury; that is, right, left, and interval censoring. The best fits from different distributions were based on the Akaike information criterion; mean and plus and minus 95% confidence intervals were obtained; and normalized confidence interval sizes (quality indices) were determined at 5, 10, 25, and 50% risk levels. The normalization was based on the mean curve. Using human-equivalent age as 45 years, data were normalized and risk curves were developed for the 50th and 5th percentile human size of the dummies.Results: Out of the available 114 tests (76 fracture and 38 no injury) from 5 groups of experiments, survival analysis was carried out using 3 groups consisting of 62 tests (35 fracture and 27 no injury). Peak forces associated with 4 specific risk levels at 25, 45, and 65 years of age are given along with probability curves (mean and plus and minus 95% confidence intervals) for PMHS and normalized data applicable to male and female dummies. Quality indices increased (less tightness-of-fit) with decreasing age and risk level for all age groups and these data are given for all chosen risk levels.Conclusions: These PMHS-based probability distributions at different ages using information from different groups of researchers constituting the largest body of data can be used as human tolerances to lower leg injury from axial loading. Decreasing quality indices (increasing index value) at lower probabilities suggest the need for additional tests. The anthropometry-specific mid-size male and small-size female mean human risk curves along with plus and minus 95% confidence intervals from survival analysis and associated IRV data can be used as a first step in studies aimed at advancing occupant safety in automotive and other environments. 相似文献
36.
ROBYN S. WILSON 《Conservation biology》2008,22(6):1452-1460
Abstract: Despite advances in the quality of participatory decision making for conservation, many current efforts still suffer from an inability to bridge the gap between science and policy. Judgment and decision‐making research suggests this gap may result from a person's reliance on affect‐based shortcuts in complex decision contexts. I examined the results from 3 experiments that demonstrate how affect (i.e., the instantaneous reaction one has to a stimulus) influences individual judgments in these contexts and identified techniques from the decision‐aiding literature that help encourage a balance between affect‐based emotion and cognition in complex decision processes. In the first study, subjects displayed a lack of focus on their stated conservation objectives and made decisions that reflected their initial affective impressions. Value‐focused approaches may help individuals incorporate all the decision‐relevant objectives by making the technical and value‐based objectives more salient. In the second study, subjects displayed a lack of focus on statistical risk and again made affect‐based decisions. Trade‐off techniques may help individuals incorporate relevant technical data, even when it conflicts with their initial affective impressions or other value‐based objectives. In the third study, subjects displayed a lack of trust in decision‐making authorities when the decision involved a negatively affect‐rich outcome (i.e., a loss). Identifying shared salient values and increasing procedural fairness may help build social trust in both decision‐making authorities and the decision process. 相似文献
37.
研究了紫外光照射下水环境中不同形态的无机氮(NO-3、NO-2和NH+4)对甲芬那酸(MEF)光解的影响.NO-3与NO-2均促进MEF的光解,NH+4对MEF的光解基本无影响;在NO-3、NO-2存在下添加适量异丙醇,显著抑制MEF的降解,实验表明NO-3、NO-2在光照下产生了·OH并参与对MEF的氧化降解.同时模拟研究了水体处于不同p E值下,水中存在的不同形态的无机氮对MEF光解的复合影响,其对MEF光解促进作用不是简单的叠加关系,增大p E值,MEF的光解速率先增大后减小.当NO-2和NH+4共存时,对MEF的光解主要表现为NO-2的影响;当NO-2和NO-3共存时,两者对MEF的光解存在拮抗作用. 相似文献
38.
A method for evaluating areas for national park status 总被引:1,自引:0,他引:1
Sümer Gülez 《Environmental management》1992,16(6):811-818
A procedure for evaluating different areas as national parks based on a scoring system is proposed. A National Park Evaluation
Form (NPEF) evaluating natural, cultural, and recreational resources in accordance with international criteria for national
parks is presented. The evaluation points given to an area indicate the possibility of the area becoming a national park.
In this method, subjectivity and bias have been minimized by a special application of the Delphi technique. The method outlined
here could help in the efforts of selecting and establishing national parks in many countries. 相似文献
39.
An Exploration of the Value of Naturalness and Wild Nature 总被引:2,自引:0,他引:2
Ben Ridder 《Journal of Agricultural and Environmental Ethics》2007,20(2):195-213
The source of the value of naturalness is of considerable relevance for the conservation movement, to philosophers, and to
society generally. However, naturalness is a complex quality and resists straightforward definition. Here, two interpretations
of what is “natural” are explored. One of these assesses the naturalness of species and ecosystems with reference to a benchmark
date, such as the advent of industrialization. The value of naturalness in this case largely reflects prioritization of the
value of biodiversity. However, the foundation of our understanding of naturalness is that it describes processes that are
free of human intervention. Conflict between the two interpretations of naturalness is apparent in the claim that naturalness
can be enhanced by human intervention, in the form of ecological restoration. Although naturalness in its purest form precludes
human intervention, some human activities are also apparently more natural than others. This continuum of naturalness relates
to the autonomy of the individual from abstract instrumentalism, which describes a particular form of influence ubiquitous
in contemporary society. The value of naturalness reflects both dissatisfaction with these threats to personal autonomy, and
respect for wild nature as the embodiment of a larger-than-human realm. 相似文献
40.
The provision of green space is increasingly being perceived as an important factor for quality of life. However, green spaces often face high developmental pressure. The main objective of this study is to investigate a prospective approach to green space planning by combining three-dimensional (3D) visualization of green space scenarios and survey techniques to facilitate improved participation of the public. Aside from the ‘Status quo’, scenarios ‘Agriculture’, ‘Recreation’, ‘Nature conservation’ and ‘Wind turbines’ are visualized in three dimensions. In order to test responses, a survey was conducted both in print format and on the Internet. Overall, 49 different visualizations that belong to one of the scenarios were available in the survey and were rated according to the perceived esthetic, recreational and ecological values.The highest rated scenes include vegetation elements such as meadows with orchards, single trees, shrubs or forest. The least attractive scenes are those where buildings are highly dominant or where there are no vegetation elements.Based on the ratings for the individual images and on the corresponding scenarios, our study shows that there is high potential for improving the existing landscape. All suggested changes are either rated about equal to or considerably higher than the status quo, with the scenario ‘Nature conservation’ receiving the highest scores. 相似文献