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961.
Simplistic economic objectives such as maximisation of producer profits are of little relevance in generating information to assist in the management of natural resources beyond the individual firm level. To provide data and information to support decision-making in natural resource management, it is necessary to take into account the views of various stakeholder groups and the multiple objectives of each group, through the use of some form of multicriteria analysis (MCA). Important decisions arise in the choice of stakeholder, since this will influence the management advice generated. Many groups and individuals can be affected by resource management decisions, but it would be impractical to attempt to identify the objectives and estimate their importance for each group. Also, questions arise concerning whether or not to include government agencies (which represent the broader community) and researchers as stakeholders. A further issue concerns choosing representative samples of stakeholder groups, from which to obtain preference data. Discussions with modellers and a reading of the literature would suggest that the choice of stakeholder groups and representatives is conducted haphazardly and is perhaps biased, and that a more systematic approach is needed. This article explores the above issues with reference to a number of multicriteria analyses, including local studies. 相似文献
962.
Volker Berding Stefan Schwartz Michael Matthies 《Environmental science and pollution research international》2000,7(3):147-158
Regional PECs (Potential Environmental Concentrations) calculated with the software EUSES were compared with measured values
using different emission and environmental distribution scenarios. The environmental data set recommended in EUSES (default
data set) represents a generic standard region. In different scenarios the parameters of the generic region are replaced by
concrete values, and estimated parameters (emissions, degradation rates and partition coefficients) are substituted by measured
or investigated values. Deviations with regard to the measured values can be up to three orders of magnitude. Despite the
basically conservative approximations, underestimations can occur. However, these are usually due to poor monitoring data
or inappropriate input values. The use of regional data instead of default parameters only slightly ameliorates the results.
The use of real emission and degradation rates alone can improve the results significantly. 相似文献
963.
测定了长时间保存的1.0000g/L苯酚贮备液的浓度和标样。结果表明此浓度的苯酚贮备液可在3年内保持稳定。 相似文献
964.
抛煤机链条炉属于半悬浮燃烧型锅炉 ,具有着火条件好、燃烧强烈、煤种适应性强和负荷调节灵敏等其他炉型所不具备的优点 ,但在实际运行中 ,该炉型又有排烟黑度高、含尘浓度大的缺点 ,大大超过环保要求的锅炉排烟标准 ,其生产及应用受到极大限制 ,因此 ,有效解决抛煤机链条炉消烟除尘问题具有十分现实的意义。本文对抛煤机链条炉普遍存在的排烟超标、出力不足、热效率低下等问题进行了详细分析 ,并结合实际提出了改进措施 相似文献
965.
Managing Endangered Species Within the Use–Preservation Paradox: The Florida Manatee (Trichechus manatus latirostris) as a Tourism Attraction 总被引:1,自引:0,他引:1
A significant challenge to wildlife managers in tourism settings is to provide visitors with opportunities to observe rare and endangered wildlife while simultaneously protecting the target species from deleterious impacts. Nearly 100,000 people annually visit Crystal River, Florida, USA to observe and swim with the Florida manatee, an endangered species. This research aimed to investigate and describe human-manatee interactions in a tourism context, to understand the salient issues related to such interactions as identified by stakeholders, and to recommend a course of action to address multiple interests in the planning and management of human-manatee interactions. Five issues were identified by all stakeholder groups: water quality, harassment, density and crowding, education, and enforcement. Currently, the U.S. Fish and Wildlife Service, which is responsible for manatee management, does not have mechanisms in place to manage the tourism component of the manatee encounter. Although a regulatory approach can be taken, a better approach would be to create an organization of tour operators to establish "best practices" that reflect the goal of the managing agency to enhance manatee protection (and thus ensure their livelihood) and to enhance the visitor experience. 相似文献
966.
967.
968.
根据深圳特区拟建隔声屏障道路的筛选原则,全面考虑了城市道路交通噪声污染程度?受污染的人口数?道路特点及立地条件,采用逐步筛选方法,得到深圳特区拟建隔声屏障的路段?调查发现:临街建筑物受交通噪声污染最严重的高度一般在12~15m?交通噪声污染的主要频率在500~2000Hz之间,频率分布与路型和车型基本无关 相似文献
969.
二相厌氧消化工艺硫酸盐还原细菌的研究 总被引:16,自引:2,他引:14
采用厌氧操作技术和MPN法测定表明,产酸相中的SRB含量为2.0-5.7×106个/ml,产甲烷相中含量为0.93-9.3×107个/ml,2者之差一般约为1个数量级.单相UASB反应器的SRB含量与产甲烷相类似.在产酸相与产甲烷相的上部悬浮液中SRB含量分别为7.5×105和4.3×105个/ml,底部污泥中SRB含量分别为2.5×106和2.5×107个/ml.SRB与产甲烷细菌相比,具有较强的环境适应能力和较小的附着能力.此外,分析讨论了SRB的生长和分布特性对反应器中硫酸盐还原作用和产甲烷作用的影响与控制. 相似文献
970.
3株真菌对活性艳蓝KN-R的脱色条件 总被引:11,自引:0,他引:11
从受污染土壤中筛选出具有广谱脱色的优势菌17株,并进一步扩大染料范围,筛选出3株对偶氮、蒽醌、三苯甲烷染料均有较好脱色效果的优势菌株. 3株菌分别为青霉属(菌Ⅰ、菌Ⅱ)和头孢霉属(菌Ⅲ)的真菌;以染料配水为例,探讨了pH值、温度、碳源、氮源因素对菌株脱色的影响;并进行了实际废水的脱色实验,结果表明该菌在pH值5~9, 温度18~37℃的区间内,且外加葡萄糖提供0.5%碳源时对染料废水的脱色率可达70%. 因此对处理染料污染废水具有较好的应用前景. 相似文献