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601.
企业是循环经济的基本单元和"小循环"的载体,其循环经济相关指标体系的设计受到越来越多的重视.在辨析循环经济、清洁生产和环境友好企业等概念基础上,分别综述和探讨了企业清洁生产、环境友好企业和循环经济指标体系,并给出相应的对策建议:(1)配合国家试点工作,尽快有针对性地设立企业循环经济指标;(2)企业循环经济指标的设立可以采取分步走的策略;(3)应把生产者责任延伸和消费者付费思想体现在循环经济指标中;(4)尤其要关注组装和间歇制造业的循环经济指标. 相似文献
602.
The aim of this paper is to show how the environmental practices of a restaurant may be evaluated in a quantitative way. For this, a new methodology, sustainable development records (SDR), was used. This allows financial, environmental and social aspects of an operation to be handled in a systematic way. The results of the two sustainable development audits show that the restaurant washes more dishes per unit of chemicals used in 1994 than in 1991. However, there is a negative trend regarding the number of meals served per unit of water used and waste generated, which suggests that the restaurant in 1994 is more wasteful with these resources than in 1991. On the other hand, this might be explained by the fact that the restaurant has increased its use of primary products. The environmental ratios are increasing for both chemicals and energy, which means that more and more of the resources used are environmentally acceptable. The lowest environmental ratios are those for provisions (<2%) and transportation (<5%), which means that not more than 2% of the provisions and 5% of the transportation are environmentally acceptable in the long run. The restaurant's ratio of satisfied customers as well as its environmental image is improving, while the profitability has not changed. The results of this paper point to a general problem of environmental auditing in regard to the evaluation of perceived positive or negative developments of an individual enterprise, since there might be an opposite implication for the larger system. It is therefore crucial to look at several hierarchical levels in order to be able to assess the effects of environmental measures. 相似文献
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605.
KENICHI OZAKI† MASAHIRO ISONO† TAKAYUKI KAWAHARA† SHIGEO IIDA† TAKUMA KUDO† KENJI FUKUYAMA† 《Conservation biology》2006,20(5):1507-1515
Abstract: Although species with large area requirements are sometimes used as umbrella species, their general utility as conservation tools is uncertain. We surveyed the species diversity of birds, butterflies, carabids, and forest-floor plants in forest sites across an area (1600 km2 ) in which we delineated large breeding home ranges of Northern Goshawk ( Accipiter gentilis ). We tested whether protection of the home ranges could serve as an effective umbrella to protect sympatric species of the four taxa. We also used an empirical habitat model of occupancy of home range to examine mechanisms by which the Northern Goshawk acts as an umbrella species. Among species richness, abundance, and species composition of the four taxa, only abundance and species composition of birds differed between sites located inside and outside home ranges, which was due to greater abundance of bird species that were prey of Northern Goshawks inside the home ranges. Thus, although home range indicated areas with high abundance of certain bird prey species, it was not effective as an indicator of the species diversity of all four taxa. We also did not find any difference in species richness, abundance, and species composition between sites predicted as occupied and unoccupied using the habitat model. In contrast, when we selected sites on the basis of each habitat variable in the model, habitat variables that selected sites either in agricultural or forested landscapes encompassed sites with high species richness or particular species composition. This result suggests that the low performance of the Northern Goshawk as an umbrella species is due to this species' preference for habitat in both agricultural and forested landscapes. Species that can adjust to changes in habitat conditions may not act as effective umbrella species despite having large home ranges. 相似文献
606.
指示生物及其在环境保护中的应用 总被引:37,自引:2,他引:37
环境监测是污染治理和环境管理的重要工具。传统的理化监测和单一的理化指标难以测定和反映污染物的综合生物学效应。利用指示生物开展生物监测,能在一定程度反映出环境污染的综合生物学效应,是环境监测行之有效的手段之一。 相似文献
607.
在B元素地球化学讨论基础上 ,采用地球化学场分析研究方法与理论 ,以秦岭柞山泥盆纪沉积盆地及凤太泥盆纪沉积盆地内B地球化学场为实例 ,探讨对B的地球化学场分析与研究。认为B的地球化学场是由热水同生沉积作用所形成 ,B异常场可用于追迹和示踪热水流体场的活动范围。可能在八卦庙含金脆韧性剪切带中 ,部分电气石石英脉及菊花状电气石集合体富集部位是在后期脆韧性剪切变形过程中同构造期所形成 ,岩浆侵位及构造动热改造为富B层位中B的活化提供了能量 相似文献
608.
生态系统健康评价研究进展 总被引:15,自引:1,他引:15
介绍了生态系统健康概念的发展状史以及生态系统健康学的主要研究内容,阐述了生态系统健康评价与环境管理的关系,建立了生态系统健康评价指标体系。 相似文献
609.
Peggy?Gunkel Estelle?Roth Bernard?FabreEmail author 《Environmental Chemistry Letters》2004,2(2):99-103
We studied copper uptake by maize grown on soils that have been contaminated with CuSO4. In soil the total copper level ranged from 24 to 135 mg kg–1. The copper distribution in soil fractions was assessed by sequential extraction, showing that anthropogenic copper is mainly concentrated in oxides fractions. The copper concentration of maize at the maturity stage reached values from 36.3 to 65.9 mg kg–1 compared to copper levels usually found in non-contaminated crops (5–30 mg kg–1). Here we demonstrate that copper can be accumulated by maize and that copper concentration in maize can be predicted by equations including copper concentration of soil fractions. 相似文献
610.
土壤的芘污染与土壤酶活性 总被引:2,自引:0,他引:2
选择芘作为多环芳烃(PAHs)代表污染物、敏感土壤酶作为污染物的生态毒理指标,探讨芘暴露下土壤酶活性的变化。结果表明:芘的添加浓度>50μg·kg-1时,对土壤脲酶、土壤脱氢酶活性有先抑制、后激活的作用,对土壤磷酸酶活性有激活作用;芘的添加浓度为50~1200μg·kg-1时,对土壤过氧化氢酶活性没有影响。土壤脲酶、脱氢酶、磷酸酶活性有可能作为芘污染土壤的生态毒理指标。 相似文献