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991.
The foundation for the creation of eco-efficiency metrics for industrial impacts on biodiversity is considered. Because biodiversity is the essence of life itself, these metrics are essential for effectiveness in the theory and practice of eco-efficiency, particularly in the case of primary natural resource extraction industries such as fishing and forestry. The case of fishing is examined, with particular attention to by-catch, lost nets, and habitat damage caused by mobile fishing gears. It is appropriate to examine fishing because industrial era impacts on marine biodiversity have been severe and are driving large and deleterious changes in marine ecosystems. For discarded by-catch, it is proposed that an eco-efficient metric for the value per unit mass of discarded fish can be set to be equivalent to that of the market value of the utilized catch. In estimating the eco-efficient value of the catch, the value of the discarded fish is then subtracted from the market value of the catch. Fish killed in lost nets can be treated similarly. It is more difficult to address marine habitat damage by mobile fishing gear, which has the highest potential for ecological injury.By using the approach proposed, negative eco-efficiencies are obtained under circumstances in which the collateral damage to biodiversity exceeds the economic benefit obtained. This is a logical outcome given the long-term effects of biodiversity decline. A metric is also proposed for assessing whether avoidance of harm to biodiversity, in the form of switching fishing gear, is required. Lastly it is proposed that metrics might be developed to provide eco-efficiency credit for companies taking effective actions to improve, or actively participate in, ecosystem-based fisheries management.  相似文献   
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Noroviruses are the major cause of non-bacterial acute gastroenteritis outbreaks in humans, with few reports about the occurrence of the norovirus GIV strain. We investigated the presence of norovirus GIV in surface water (river, bay, and stream) and untreated sewage, and we determined a positivity rate of 9.4 % (9/96). The strains genotyped were GIV.1. To our knowledge, this is the first report of GIV in Brazil.  相似文献   
995.
Many parasitoid wasps learn host-associated cues and use them in subsequent host-searching behavior. This associative learning, namely “oviposition learning,” has been investigated in many studies. However, few studies have compared multiple species, and no comparative study has previously been conducted on ectoparasitoid species. We compared the effects of oviposition learning on host preference and offspring sex ratio in two closely related ectoparasitoid wasps with contrasting reproductive strategies, Anisopteromalus calandrae (r-strategist) and its sibling species (K-strategist). Using two bruchine hosts, Callosobruchus chinensis and Callosobruchus maculatus larvae infesting the cowpea Vigna unguiculata, oviposition choice experiments were performed at high and low host densities. In both species, no conspicuous effect on the offspring sex ratio was detected, but effects on host preference were found to differ between the species. In A. calandrae, the effects were detected only at high host density, suggesting that oviposition learning plays a role in host discrimination from a short distance but not from a long distance. In the sibling species, those effects were not detected in any of the cases, suggesting the absence of oviposition learning. These results are compatible with those of previous comparative studies of endoparasitoid wasps in that few lifetime oviposition experiences and/or low reward per foraging decision result in low or absent oviposition learning ability. This finding may indicate that ecological traits contributing to learning ability are similar between endoparasitoid and ectoparasitoid wasps. Thus, our species comparison of ectoparasitoids provides another model system for investigating learning and memory dynamics in parasitoid wasps.  相似文献   
996.
This study presents detailed and comprehensive inventories on the horticultural production of tomato using compost (CM) or mineral fertilizers (M), in both open-fields (OF) and greenhouses (GH), providing information on the environmental impacts and assessing the agronomic viability of the four cultivation options. Life cycle assessment (LCA) was used to calculate the potential environmental impacts of the tomato production cycle per ton of product. The stages in the assessment included: mineral and organic fertilizers production, fertilizers transport, cultivation stage and greenhouse stage. The data were obtained experimentally in pilot fields and in an industrial composting facility using municipal organic waste, both located in the Mediterranean area. The results indicate that replacing a fraction of the mineral fertilizers dosage with compost is a good option, as this did not alter yield or fruit size parameters. Greenhouse protection increased infrastructure materials requirements but enhanced harvest by almost 50% and reduced the water and pesticides requirement. Compost production and greenhouse stages were the most impacting stages. Without subtracting the avoided burdens by composting and not dumping organic waste, the cultivation option OF_M had the lowest and OF_CM the highest impact. When avoided burdens were taken into consideration, the environmental impacts of the four cultivation options varied, depending on the impact category, with bigger differences due to fertilization as a variable rather than the production system.  相似文献   
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998.
Journal of Polymers and the Environment - In this study cassava starch modified by ozone technology and cellulose nanofibres were used to produce films. These nanocomposites were produced by...  相似文献   
999.
Temporal dynamics in a pollination network   总被引:2,自引:0,他引:2  
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1000.
The subject of sustainability reports, especially those related to GRI, has become an interesting topic to academics and practitioners. This paper seeks to propose an easy-to-use sustainability reporting assessment tool that is suitable to the GRI G4 guidelines. Our idea is to provide a tool that can be applied by an organization, based in GRI indicators, in a quick and easy way. The tool, called G-Index, represents the organizational sustainability performance. The index is a sum of four factors, and a questionnaire about the GRI elements raised the data to elaborate a Mudge diagram, which was used to define the weight values. Finally, the method for the evaluation tool was established, and a case study with the automotive sector was performed. The results showed us the G-Index represents a good option to assess the organization’s disclosure practices in sustainability reports based on the GRI framework. The report analysis presented some important facts, it is more common the disclosure of the Management Approach then the application of External Assurance. Furthermore, even the General Standard Disclosures of the GRI guidelines being mandatory, some companies do not fully disclose them, as shown in the GS factor, that makes up, the G-Index.  相似文献   
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