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The aim of this paper is to compare the criteria for eco-labeling of wild-caught fish in the Norwegian eco-certified fisheries, and to study if these eco-labels affect the harvesting patterns of Norwegian fishermen. The eco-labels Marine Stewardship Council (MSC), KRAV and Friend of the Sea (FOS) as applied in 2009 were studied. In this study, the harvesting patterns are defined by using the following parameters: season, catch area, size of fishing vessel, gear type, bycatch, location of landing site and distance to the fishing ground. KRAV had more specific criteria than did MSC and FOS in specific fisheries regarding time of the fishing effort, catch area, size of fishing vessels, gear type (e.g. hook size, and the use of beam trawlers was not permitted) and distance to the fishing ground. The findings show that few of the eco-label requirements influenced these aspects in Norwegian fisheries.  相似文献   
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在水深为1.5 m的水道中,研究了不同收割强度(0、15、30、45、60、75、90和105 cm)对菹草生长和光合荧光特性的影响.结果表明:(1)收割对菹草枝条生长和恢复影响显著.对照组(0 cm)株高最大,并在水面形成冠层.15 cm组在实验第20 d恢复,30~105 cm组恢复率分别为69.67%、17.78%、8.83%、5.33%、2.28%和1.90%.(2)收割显著降低了菹草的生物量.与对照组相比,收割组鲜重增加量分别下降了23.71%、54.90%、81.19%、85.82%、90.72%、94.07%和95.10%.15~105 cm收割组最终生物量则分别下降为对照组的59.36%、43.16%、27.69%、18.73%、14.66%、8.14%和4.07%.(3)收割使菹草营养繁殖体(石芽)数量、个体大小和鲜重显著降低.(4)中、低强度收割对菹草叶片最大光化学量子产量(Fv/Fm)影响不明显,而高强度收割组(尤其是105 cm)Fv/Fm显著下降.菹草叶片快速光响应曲线ETRmax差异不显著;中、低强度收割组ETRmax略有上升,而高强度收割组ETRmax出现下降.由结果可知,收割对控制菹草生物量和繁殖体数量效果明显,但以中、低收割强度为宜.  相似文献   
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The present study characterised the socio-economic, operational and technical aspects of harvesting the gooseneck barnacle (Pollicipes pollicipes) along the southwestern coast of Portugal. For this purpose, face-to-face interviews were conducted with commercial harvesters of the two most representative fishery associations (covering 51% licensed harvesters) in the area of the Parque Natural do Sudoeste Alentejano e Costa Vicentina. Based on traditional ecological knowledge, this study confirmed the local importance, ancestral character and family traditions of this activity, which constitutes the exclusive occupation of nearly half of the interviewed harvesters and an important source for household incomes. In addition, data was also gathered on preferential fishing zones, harvesting effort and duration, daily catches and selling prices. The main concerns, problems and difficulties experienced in this activity relate to the excessive number of recreational harvesters, creating problems at the levels of exploitation, commercialisation, management and inspection. The study further confirms the rising interest and involvement of the commercial harvesters in enhancing the competences of the local fishery associations. In particular, local harvesters want to encourage the development of a co-management system comprising spatial-temporal measures to avoid conflicts of use over space and resources, as well as innovative marketing strategies to improve the recognition, value and traceability of the shellfish. Overall, the information gathered is most valuable for adopting an alternative approach based on the cooperation and co-responsibility at local and regional levels, involving the stakeholders in the proposal of management measures adapted to the specificities of this area, activity and resource.  相似文献   
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