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881.
Dagmara Nawrocka Torbjörn Brorson Thomas Lindhqvist 《Journal of Cleaner Production》2009,17(16):1435-1443
This paper focuses on the role of ISO 14001 in environmental supply management practices in Swedish companies. It discusses the existing and potential role of ISO 14001 for three key operational tasks of environmental supply chain management: to communicate the requirements to the supplier, to motivate and enable the supplier, and to verify that the supplier follows the requirements. The study used three different research methods: interviews with environmental managers, focus group discussions and a survey of two multinational companies and their operating units in several countries.It concludes that cooperation between the purchasing and environmental functions within a company is frequently not sufficiently achieved in implementation of ISO 14001; this makes the communication of customer requirements to suppliers less efficient. Building close relationships with suppliers is important to overcome initial difficulties, but this often conflicts with having a large supplier base. For the supplier to have an ISO 14001 certificate is seldom an absolute requirement, however, preference is often given to such suppliers. The value of the ISO 14001 certificate, as a proof of environmental performance, is a combination of the supplier's environmental ambitions, the advancement of supply chain practices of the customer and the ambitions of the certification bodies. Supplier audits are not commonly used as they are resource-consuming. Monitoring and verification approaches need further development. 相似文献
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Asbj?rn Haaning Nielsen Jes Vollertsen Thorkild Hvitved-Jacobsen 《Water environment research》2006,78(3):275-283
Kinetics and stoichiometry of aerobic chemical and biological sulfide oxidation in wastewater from sewer networks were studied. In this respect, the effects of temperature and pH were investigated in the ranges 10 to 20 degrees C and 5 to 9, respectively. The temperature dependency of sulfide oxidation kinetics was described using an Arrhenius relationship. The effect of pH on the rate of chemical sulfide oxidation is related to the dissociation of hydrogen sulfide (H2S) to hydrogen sulfide ion (HS(-)), with HS(-) being more readily oxidized than H2S. Biological sulfide oxidation exhibited the highest rates at ambient wastewater pH, and the reaction was inhibited at both low and high pH values. Chemical sulfide oxidation was found to produce thiosulfate and sulfate, while elemental sulfur was the main product of biological sulfide oxidation. Based on the investigations, general rate equations and stoichiometric constants were determined, enabling the processes to be incorporated to conceptual sewer process models. 相似文献
883.
Lisa Leimar Price Astrid Björnsen Gurung 《Environment, Development and Sustainability》2006,8(4):507-517
The paper presents a methodology that guided several ethnoentomological research projects and goes on to examine and compare the results from two independent research locations in Asia. The first location is in the Philippines, a Green Revolution area that has been heavily impacted by extension messages and insecticide use. The second location is in Nepal which has a traditional subsistence orientation and has remained widely unaffected by agricultural modernization. The paper emphasizes the differences and similarities of the results from the two sites and discusses the role of the methodology and methods used in capturing ethnoentomological knowledge, particularly with regard to insect pests in rice. The results of both investigations share the importance of agronomic criteria among farmers in insect classification and sorting criteria, thus highlighting the relevance of functional criteria. Farmers at both research sites have difficulties in identifying the lifecycles of insects. We discuss the issues of tradition and change in farmer entomological knowledge and providing support to the knowledge base of farmers though programs like IPM-Farmer Field Schools as opposed to broad-based recommendations for crop pest management.Article type: MS-ENVI-SI ETHNOSCI MS04 Contribution to Environment, Development & Sustainability, special issue ‘Bridging the gap between natural resources and their human management for the future using ethnoscience’. 相似文献
884.
Christian Ramp Wilhelm Hagen Per Palsbøll Martine Bérubé Richard Sears 《Behavioral ecology and sociobiology》2010,64(10):1563-1576
Analyses of social structures in baleen whales are rare, and so far, they are thought to consist of mostly short and unstable
associations. We investigated the association patterns of individual humpback whales from a summer feeding aggregation in
the Gulf of St. Lawrence from 1997 to 2005. Photo-identified animals were sexed using genetic methods and were grouped into
five categories: juvenile males/females, mature males and lactating/non-lactating females. We calculated half-weight association
indices within and between the groups and found that 45% of the observation showed single animals and another 45% small groups
(two to three) consisting mainly of mature animals besides lactating females. Using permutation tests, we found evidence for
long-term associations between mature males and non-lactating females as well as among non-lactating females. Standardised
lagged association rates revealed that these male–female groups disassociated quickly over about 2 weeks, whereas associations
increased again towards the beginning of the breeding season. Non-lactating females of similar age engaged in multi-seasonal
stable pairs for up to six consecutive feeding seasons; no mature male–female association was observed in consecutive years.
The females with the most stable and long-term associations also had the highest reproductive output. While the risk of predation
could not explain these long-term bonds, feeding cooperation seemed the most plausible explanation for group forming behaviour
during the summer months. 相似文献
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