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891.
Rita Gamito Célia M. Teixeira Maria J. Costa Henrique N. Cabral 《Regional Environmental Change》2013,13(2):413-421
For each Portuguese fleet component, landings of biogeographic groups of fish species were compared for the period of 1993–2009. Wide-distribution species were the most abundant in landings, but have shown a decreasing trend. Temperate species had higher landings in trawl fisheries, whereas subtropical species were most abundant and exhibiting an increasing trend in landings of multi-gear fisheries. A latitudinal gradient was observed, with landings of temperate species being more important in the North-western coast than in the South-western and South coasts. Although trawl fisheries were relatively more important in the North-western coast, there has been a recent increase in the relative importance of multi-gear fisheries and of subtropical species in this area. The increasing relative importance of subtropical species in Portuguese fisheries along with the fact that landings of subtropical species were higher in multi-gear fisheries could indicate an easier adaptation of Portuguese multi-gear fisheries to the effects of climate change. However, as multi-gear fisheries include a wide range of gears, techniques and target-species, they may not all respond in the same manner to changes in fish species’ distribution. Among multi-gear fisheries, trammel nets catch a wider variety of species and a wider size range than gill nets or longlines; thus, trammel net fishers can adapt to changes in abundance of the main target species more readily than those using more species- and size-specific gears. Therefore, trammel net fisheries could more easily adapt to the effects of climate change on fish distribution than gill net or longline fisheries. 相似文献
892.
Mohamed Elhag Aris Psilovikos Maria Sakellariou-Makrantonaki 《Environment, Development and Sustainability》2013,15(5):1189-1204
Sustainable water resources management plans depend on reliable monitoring of land use –land cover (LULC) changes. The use of the remote sensing techniques in LULC changes detection brings consistency and reliability to the decision maker at regional scale. Three temporal data sets of images were used to obtain the land cover changes in this study: Landsat-5 Thematic Mapper (TM) acquired in 1984, and Landsat-7 enhanced Thematic Mapper acquired in 2000 and 2005 consequently. Each temporal data set consists of four Landsat scenes, which were mosaicked to cover the whole Nile Delta. Two different supervised classification algorithms were implemented to produce classification maps in thematic form. Support vector machine showed higher classification accuracies in comparison with maximum likelihood classification. The results indicated that the rapid imbalance changes occurred among three land cover classes (urban, desert, and agricultural land). These changes powered the land degradation and land fragmentation processes over the agricultural land exclusively due to urban encroachment. Slight land cover changes were detected between fish farms and surface water land cover classes. 相似文献
893.
Maria G Ioannides Peter J. Papadopoulos Eugenia Dimitropoulou 《International journal of occupational safety and ergonomics》2013,19(1):87-100
A system consisting of an electric machine and a human body is studied and the resulting electric field is predicted. A 3-phase induction machine operating at full load is modeled considering its geometry, windings, and materials. A human model is also constructed approximating its geometry and the electric properties of tissues. Using the finite element technique the electric field distribution in the human body is determinedfor a distance of 1 and 5 m from the machine and its effects are studied. Particularly, electric field potential variations are determined at specific points inside the human body and for these points the electric field intensity is computed and compared to the limit values for exposure according to international standards. 相似文献
894.
Maria A. Tsiafouli Evangelia Apostolopoulou Antonios D. Mazaris Athanasios S. Kallimanis Evangelia G. Drakou John D. Pantis 《Environmental management》2013,51(5):1025-1033
The Natura 2000 network was established across the European Union’s (EU) Member States with the aim to conserve biodiversity, while ensuring the sustainability of human activities. However, to what kind and to what extent Natura 2000 sites are subject to human activities and how this varies across Member States remains unspecified. Here, we analyzed 111,269 human activity records from 14,727 protected sites in 20 Member States. The frequency of occurrence of activities differs among countries, with more than 86 % of all sites being subjected to agriculture or forestry. Activities like hunting, fishing, urbanization, transportation, and tourism are more frequently recorded in south European sites than in northern or eastern ones. The observed variations indicate that Natura 2000 networks are highly heterogeneous among EU Member States. Our analysis highlights the importance of agriculture in European landscapes and indicates possible targets for policy interventions at national, European, or “sub-European” level. The strong human presence in the Natura 2000 network throughout Member States, shows that conservation initiatives could succeed only by combining social and ecological sustainability and by ensuring the integration of policies affecting biodiversity. 相似文献
895.
Tropical forest countries are struggling with the partially conflicting policy objectives of socioeconomic development, forest conservation, and safeguarding the livelihoods of local forest-dependent people. We worked with communities in the lower Tapajós region of the central Brazilian Amazon for over 10 years to understand their traditional and present land use practices, the constraints, and decision making processes imposed by their biophysical, socioeconomic, and political environment, and to facilitate development trajectories to improve the livelihoods of forest communities while conserving the forest on the farms and in the larger landscape. The work focused on riverine communities initially in the Tapajós National Forest and then in the Tapajós–Arapiuns Extractive Reserve. These communities have a century-old tradition of planting rubber agroforests which despite their abandonment during the 1990s still widely characterize the vegetation of the river banks, especially in the two protected areas where they are safe from the recent expansion of mechanized rice and soybean agriculture. The project evolved from the capacity-building of communities in techniques to increase the productivity of the rubber agroforests without breaking their low-input and low-risk logic, to the establishment of a community enterprise that allowed reserve inhabitants to reforest their own land with tree species of their choice and sell reforestation (not carbon) credits to local timber companies while retaining the ownership of the trees. By making land use practices economically more viable and ecologically more appropriate for protected areas, the project shows ways to strengthen the system of extractive and sustainable development reserves that protects millions of hectares of Amazon forest with the consent of the communities that inhabit them. 相似文献
896.
dos Santos Filho Edson Antônio Siqueira Danilo Diniz Araújo Edcleide Maria Luna Carlos Bruno Barreto de Medeiros Everaldo Paulo 《Journal of Polymers and the Environment》2022,30(2):443-460
Journal of Polymers and the Environment - Nowadays, there is a need to obtain eco-friendly materials, especially plastics that are responsible for most of the environmental pollution. In this... 相似文献
897.
Nolasco Maria E. Lemos Viviane A. S. López Gina Soares Sandra A. Feitosa Johnny P. M. Araújo Bruno S. Ayala Alejandro P. de Azevedo Marleane M. F. Santos Francisco E. P. Cavalcante Rivelino M. 《Journal of Polymers and the Environment》2022,30(7):2862-2874
Journal of Polymers and the Environment - The aim of the present study was to perform morphological and chemical characterizations of microplastics (MPs) found in seawater samples from the coast of... 相似文献
898.
da Rosa Salles Theodoro da Silva Bruckamann Franciele Viana Altevir Rossato Krause Luciana Maria Fontanari Mortari Sergio Roberto Rhoden Cristiano Rodrigo Bohn 《Journal of Polymers and the Environment》2022,30(7):2695-2713
Journal of Polymers and the Environment - This study reports a simple methodology of obtaining magnetic nanocrystalline cellulose under very mild conditions employing only Fe2+ as the iron source,... 相似文献
899.
Pontoni Ludovico La Vecchia Claudia Boguta Patrycja Sirakov Maria DAniello Enrico Fabbricino Massimiliano Locascio Annamaria 《Environmental Chemistry Letters》2022,20(1):797-812
Environmental Chemistry Letters - Heavy metals are occurring in the aquatic environment as the result of natural or anthropogenic inputs, and depending on concentration, availability and resilience... 相似文献
900.
Lastre-Acosta Arlen Mabel Rocha Carolina Mendes Mendes Maria Anita Teixeira Antonio Carlos Silva Costa do Nascimento Claudio Augusto Oller 《Environmental science and pollution research international》2022,29(28):42231-42241
Environmental Science and Pollution Research - Polychlorinated biphenyls (PCBs) are a family of highly toxic, resistant, and persistent organic pollutants, among which 2-chlorobiphenyl (PCB-1) is... 相似文献