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51.
Valentina Milana Paolo Franchini Luciana Sola Elisa Angiulli Anna Rita Rossi 《Marine Biology》2012,159(2):399-411
Atherina boyeri is a common inhabitant of the Mediterranean brackish and coastal waters. Several recent studies proposed the recognition
of three distinct forms/species (one lagoon/freshwater and two marine) within an A. boyeri complex. In this study, we used 10 newly available microsatellite loci to better define the genetic structure of the lagoon
form. A total of 428 fishes from 11 lagoons along the Italian and Albanian coasts and three Italian lakes were analyzed. A
pronounced genetic spatial structure was confirmed for all considered geographic scales (near, medium and broad). A restricted
gene flow was detected, suggesting reduced population connectivity. The comparison of present data and previous studies, based
on mtDNA and RAPD markers, allowed a preliminary identification of the roles of recent factors (gene flow, habitat discontinuity
and water currents) and past events (e.g., Pleistocene glaciations) in shaping the pattern of genetic differentiation. 相似文献
52.
Daniela Cianelli Luciana Sabia Maurizio Ribera dAlcal Enrico Zambianchi 《Ecological modelling》2009,220(19):2380-2392
In marine ecosystems ecological and environmental conditions continuously change, possibly supporting the wide range of phytoplankton species coexisting in aquatic environments. Phytoplankton communities are not homogeneously distributed in the water column due to the spatial and temporal variability of turbulent mixing and the concurrent biological response. In this paper an individual-based model (Lagrangian method) simulating the basic physiology of two coexisting phytoplankton species has been developed. The species, sharing the same availability of light and nutrient resource, are characterized by different photo-physiological parameters. The spatial and temporal evolution of turbulent mixing is simulated introducing vertical profiles of measured eddy diffusivity. Three case studies have been examined to analyze the role of environment–individual interactions in determining bloom conditions for both the selected species. The organisms experience recurrent fluctuations of light, temperature, and nutrient concentration gradients, due to the turbulent mixing in the water column, which have significant effects on the growth of the phytoplankton species. In all the numerical experiments, the temporal and spatial variability of different forcings do not support the prevalence of one species over the other over the time scale typical of a phytoplankton bloom.A well mixed water column favours the growth of both the populations while a variable mixing regime limits their growth reducing the photophysiological differences between the species. 相似文献
53.
Ulysses Paulino de Albuquerque Luciana Gomes de Sousa Nascimento Fabio José Vieira Cybelle Maria de Albuquerque Duarte Almeida Marcelo Alves Ramos Ana Carolina Oliveira da Silva 《Journal of Agricultural and Environmental Ethics》2012,25(1):19-32
The scientific community has debated the importance of “return” activities after ethnobiological studies. This issue has provoked
debate because it touches on the ethics of research and the relationships with the people involved in these studies. This
case study aimed to investigate community perception of an ethnobotany research project that was carried out in the semi-arid
region of northeastern Brazil. Furthermore, we reported how the residents of this rural community felt about participating
in the activities of “return” that arose from the projects. Our findings demonstrate that “return” activities should be planned
from the design phase of the research until its closure as a lifelong process that allows the communities involved to gradually
take ownership of the information and actions that are being generated. Similarly, we argue that such activities must be negotiated
with the people of the community so that they have decision-making power and autonomy to decide what is most relevant to their
lives. 相似文献
54.
The problem of disposing of plaster waste from building sites: problem structuring based on value focus thinking methodology 总被引:1,自引:0,他引:1
Plaster is a material which is widely used in Brazil on construction sites. However, its use in recent years has been limited by a legal resolution on the environment introduced in Brazil. One of the regions most affected by these restrictions is the Northeast where the strategic importance of plaster for the region is apparent from the extensive economic development, centered on the gypsum pole of Araripe in the state of Pernambuco. This problem has involved many interested parties, among whom are plaster producers, plastering companies, builders, unions (for plaster workers, and construction workers), Town Halls, and so forth. Therefore, there is a need to structure the problem with a view to obtaining a better understanding of the problem given the lack of information on the real decision problem. To reach this objective, value focus thinking (VFT), a methodology that addresses how values can be used to improve the decision making process, was applied and the problem was structured. Thus, it was possible for the parties involved to clarify their objectives, and specify more precisely the consequences and constraints for the decision problem. In addition, each party involved could get a better understanding of their own wishes. In conclusion, the VFT methodology application enables the parties involved to make more consistent decisions, and therefore to ensure that plaster will continue to be used in the construction industry. 相似文献
55.
A complex picture of associations between two host mussels and symbiotic bacteria in the Northeast Atlantic 总被引:1,自引:0,他引:1
Clara F. Rodrigues Marina R. Cunha Luciana Génio Sébastien Duperron 《Die Naturwissenschaften》2013,100(1):21-31
Among chemosymbiotic metazoans found at deep-sea hydrothermal vents, cold seeps and organic falls, members of the mussel clade Bathymodiolinae (Bivalvia: Mytilidae) have evolved interactions with a higher diversity of bacterial lineages than other bivalve groups. Here, we characterized the bacteria associated with “Bathymodiolus” mauritanicus and Idas-like specimens from three sites in the Northeast Atlantic (two mud volcanoes in the Gulf of Cadiz and one seamount of the Gorringe Bank). Phylogenetic analysis of bacterial 16S rRNA-encoding gene sequences demonstrated that “B”. mauritanicus has a dual symbiosis dominated by two phylotypes of methane-oxidising bacteria and a less abundant phylotype of a sulphur-oxidising bacterium. The latter was the dominant phylotype in a sympatric population of Idas-like mussels at the Darwin mud volcano. These results are the first report of a bacterial phylotype shared between two deep-sea mussels from divergent clades. This sulphur-oxidising bacterium was absent from Idas-like specimens from the other two sites (Gorringe Bank and Meknès mud volcano), in which bacterial clone libraries were dominated by other Gammaproteobacteria related to symbionts previously identified in Idas modiolaeformis from the Eastern Mediterranean. All Idas-like specimens studied herein are closely related and also related to I. modiolaeformis. However, they probably display different associations with bacteria, with the possible absence of both methane- and sulphur-oxidising symbionts at the Gorringe Bank. These results draw a very complex picture of associations between mussels and bacteria in the Northeast Atlantic, which could be highly variable depending on locale characteristics of the habitats. 相似文献
56.
Tatyana Karpova Sergei Preis Juha Kallas Adélia Luciana Barros Torres 《Environmental Chemistry Letters》2007,5(4):219-224
The potential of the photocatalytic oxidation to selectively oxidise steroid estrogens, β-estradiol and 17α-ethynylestradiol,
in the presence of saccharose and ethanol as co-pollutants was clearly demonstrated. The alkaline media conditions remained
the most beneficial for the PCO regardless the presence of co-pollutants under consideration. Saccharose appeared to be the
more powerful competitor than ethanol. The influence of the co-pollutants is explained by their competition for the adsorption
sites and also scavenging of the OH-radicals. 相似文献
57.
Mario Sprovieri Simone Sammartino Daniela Salvagio Manta Ennio Marsella Luciana Ferraro 《Chemistry and Ecology》2006,22(1):65-91
The results of a geochemical survey carried out on the southern Campania shelf (southern Italy) are illustrated, offering a tempting opportunity to discuss the statement and definition of regional geochemical backgrounds for selected heavy metals. A total of 104 top core sediments, collected on average 1.5 km from one another and covering a shelf area of about 1300 km2, were analysed for grain size, organic carbon content (OC), and heavy-metal (As, Al, Fe, Cd, V, Cr, Zn, Cu, Ni, Hg, and Pb) concentrations. The characteristics of the area, scarcely influenced by industrial activities, and the extensive data set, make this study suitable for an appropriate multivariate and spatial geostatistical methodologies used for i) a reliable definition of large-scale marine sediments' geochemical backgrounds and ii) an accurate discrimination of different geological controls on trace-element distribution patterns. Enrichment factors estimated with respect to both the average shale composition and the weighted average metal concentrations measured in inland soils rule out significant anthropogenic inputs. A spatial-geostatistics approach (kriging of spatial component based on an accurate implementation of variographic surveying) was applied, and this is proposed as an appropriate quantitative methodology to define the geochemical backgrounds for the different heavy metals. Two nested spatial structures were identified for some of the heavy metals, thus allowing clear identification of local and regional geochemical controls related to the different spatial variability of grain size. 相似文献
58.
Dielle Monteiro Teixeira Juliana Merces Hernandez Luciana Damascena Silva Darleise de Souza Oliveira Paula Katharine de Pontes Spada Tereza Cristina Monteiro Gurjão Joana D’Arc Pereira Mascarenhas Alexandre Costa Linhares Lena Líllian Canto de Sá Morais Yvone Benchimol Gabbay 《Food and environmental virology》2016,8(1):101-104
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
59.
Walter Leal Filho Ulisses Azeiteiro Fátima Alves Paul Pace Mark Mifsud Luciana Brandli 《国际发展与全球生态学杂志》2018,25(2):131-142
The United Nations Sustainable Development Goals (UN SDGs) contain a set of 17 measures to foster sustainable development across many areas. It offers a good opportunity to reinvigorate sustainable development research for two main reasons. First, it comprises many areas of SD research, which have become mainstream thanks to the UN SDGs. Second, the fact that the UN and its member countries have committed to attaining SDGs by 2030 has added a sense of urgency to the need to perform quality research on SD on the one hand, and reiterates the need to use the results of this research on the other. Even though the basic concept of sustainability goes back many centuries, it has only recently appeared on the international political agenda. This is partly due to an awakening of the fact that the human ecological pressure on the planet is still much larger than what nature can renew or compensate for. Based on this state of affairs, this paper presents an outline of the process leading to the agreement on the UN SDGs, and looks at some of the ecological aspects as a result of continued pressure of human activities on natural resources. Furthermore, a set of research needs is proposed – also based holistically on updated research trends – discussing the degree of urgency of some measures and explaining why the UN SDGs need to be accorded greater priority in international sustainable development research efforts. 相似文献
60.
Temporal dynamical analysis in fire sequences recorded from 1992 to 2005 in a fire-vulnerable area of Patagonia (Argentina) was performed by using the Allan Factor statistics. Three typologies of fires were investigated: forest, steppe and urban. The obtained results show the presence of annual periodicities, superimposed to a time-scaling behaviour, which characterize the point processes of fires as fractal time processes with a rather high degree of time-clusterization of the events. 相似文献