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21.
Vitor H. Paiva Pedro Geraldes Iván Ramírez Ana Meirinho Stefan Garthe Jaime A. Ramos 《Marine Biology》2010,157(6):1385-1399
Many breeding seabird species are central-place foragers and constrained to find productive prey patches within their foraging
ranges. We assessed how different populations of a pelagic seabird species, the Cory’s shearwater Calonectris diomedea, breeding in oceanic and neritic conditions, cope with these constraints in the North Atlantic, during both incubation and
chick-rearing periods. We analysed 237 foraging trips to study the movements and oceanographic characteristics of foraging
habitats of seven different populations of Cory’s shearwaters. Generally, oceanic populations exhibited higher foraging effort,
by travelling more time and to more distant areas, and larger home ranges and feeding areas, than the neritic population (i.e.
breeding on an island within the Portuguese continental platform). On their short trips (i.e. ≤4 days), birds from the different
populations fed mostly in shallower waters around the colony. During long trips (i.e. ≥5 days), feeding areas of both oceanic
and neritic populations were characterized by high concentration values of chlorophyll-a, low sea-surface temperature and shallower habitats, with oceanic populations of the Azores exploiting areas north of the
islands over known seamounts and frontal regions. Birds from other oceanic population (Selvagens) also exploited the African
continental shelf system on their long trips. The home ranges of the different populations overlapped widely, but there was
a general spatial segregation in terms of the core feeding areas at the population level. Core feeding areas and areas of
foraging overlap between different populations should be important to inform conservation management measures, such as the
definition of Marine Important Bird Areas for seabirds over the North Atlantic. 相似文献
22.
Filipe R. Ceia Vitor H. Paiva Stefan Garthe João C. Marques Jaime A. Ramos 《Marine Biology》2014,161(8):1861-1872
This study tested for fluctuations on short-term consistency (within about 1 month) in the isotopic niche of a pelagic seabird species. Short-term consistency in the isotopic niche was assessed using a wide-ranging apex predator, the Cory’s shearwaters Calonectris diomedea, along a 3-year study (2010–2012), during both the pre-laying and chick-rearing periods, with markedly inter- and intra-annual differences in the foraging spatial distribution at sea and isotopic niche width. We used individual movement data and stable isotope data, analysed using recent metrics based in a Bayesian framework, of 69 adults breeding on a small neritic island in the North Atlantic (39°24′N, 009°30′W). As expected, our results confirm that isotopic niche expansion could arise via increased variation in spatial distribution at sea among individuals. Results suggest fluctuations on short-term consistency in the isotopic niche of Cory’s shearwaters related to their different foraging patterns among periods and, ultimately, to presumably temporal changes in the availability and predictability of food resources. Short-term consistency in the isotopic niche was higher and persistent during periods when the population showed an intermediate isotopic niche width and absent when isotopic niche was either smaller or larger during the study period. These results suggest that consistency in the isotopic niche is an important characteristic of this population during the breeding period that may fluctuate depending on resources availability and should be important to understand the dynamics of foraging ecology of pelagic seabirds in general. 相似文献
23.
Maísa Tatiane Ferreira de Souza Elizangela Ambrosio Cibele Andrade de Almeida Thábata Karoliny Formicoli de Souza Freitas Lídia Brizola Santos Vitor de Cinque Almeida Juliana Carla Garcia 《Environmental monitoring and assessment》2014,186(8):5261-5271
The goal of this study was to investigate the activity of the coagulant extracted from the cactus Opuntia ficus-indica (OFI) in the process of coagulation/flocculation of textile effluents. Preliminary tests of a kaolinite suspension achieved maximum turbidity removal of 95 % using an NaCl extraction solution. Optimization assays were conducted with actual effluents using the response surface methodology (RSM) based on the Box–Behnken experimental design. The responses of the variables FeCl3, dosage, cactus dosage, and pH in the removal of COD and turbidity from both effluents were investigated. The optimum conditions determined for jeans washing laundry effluent were the following: FeCl3 160 mg L?1, cactus dosage 2.60 mg L?1, and pH 5.0. For the fabric dyeing effluent, the optimum conditions were the following: FeCl3 640 mg L?1, cactus dosage 160 mg L?1, and pH 6.0. Investigation of the effects of the storage time and temperature of the cactus O. ficus-indica showed that coagulation efficiency was not significantly affected for storage at room temperature for up to 4 days. 相似文献
24.
Alexandro M.M. Vargas André L. Cazetta Clarice A. Garcia Juliana C.G. Moraes Eurica M. Nogami Ervim Lenzi Willian F. Costa Vitor C. Almeida 《Journal of environmental management》2011
Activated carbons were prepared from flamboyant pods by NaOH activation at three different NaOH:char ratios: 1:1 (AC-1), 2:1 (AC-2), and 3:1 (AC-3). The properties of these carbons, including BET surface area, pore volume, pore size distribution, and pore diameter, were characterized from N2 adsorption isotherms. The activated carbons obtained were essentially microporous and had BET surface area ranging from 303 to 2463 m2 g−1.13C (CP/MAS and MAS) solid-state NMR shows that the lignocellulosic structures were completely transformed into a polycyclic material after activation process, thermogravimetry shows a high thermal resistance, Boehm titration and Fourier-transform infrared spectroscopy allowed characterizing the presence of functional groups on the surface of activated carbons. Scanning electron microscopy images showed a high pore development. The experimental results indicated the potential use of flamboyant pods as a precursor material in the preparation of activated carbon. 相似文献
25.
T. Stoichev M. Clara P. Basto Vitor Vasconcelos M. Teresa S.D. Vasconcelos 《Chemistry and Ecology》2013,29(5):395-399
Interactions of nonylphenol (NP), a toxic and oestrogenic degradation product of widely used non-ionic surfactants, with the cyanobacterium Microcystis aeruginosa were studied. Batch cultures were incubated for 10 days with NP concentrations between 10 and 570 nM. NP was removed more quickly in the presence of M. aeruginosa (half-life 2.7–5.2 days) than in its absence (half-life 6.7–10.2 days) at all concentrations tested. At the end of the experiment, NP could not be found in the biomass, so the biotic removal is due to uptake and chemical transformation, and not to physical binding on the cells. The observed effective concentrations, EC50 and EC20, were 0.45 and 0.25 μ M, respectively. Therefore, NP is expected to have toxic effects on M. aeruginosa only in very contaminated surface waters. However, for concentrations that go far beyond environmental levels, cyanobacteria are able to cope with NP toxicity by internalising the compound in a less toxic form. Therefore, the presence of cyanobacteria may increase the rate of NP removal from the aquatic environment. 相似文献
26.
Hany Alonso José P. Granadeiro Vitor H. Paiva Ana S. Dias Jaime A. Ramos Paulo Catry 《Marine Biology》2012,159(6):1197-1207
In pelagic seabirds, who often explore distant food resources, information is usually scarce on the level of trophic segregation
between parents and their offspring. To investigate this issue, we used GPS tracking, stable isotopes and dietary information
of Cory’s shearwaters Calonectris diomedea breeding in contrasting environments. Foraging trips at Selvagem Grande (an oceanic island) mainly targeted the distant African
coast, while at Berlenga island (located on the continental shelf), shearwaters foraged mainly over nearby shelf waters. The
degree of isotopic segregation between adults and chicks, based on δ13C, differed markedly between the two sites, indicating that adult birds at Selvagem fed their chicks with a mixture of shelf
and offshore pelagic prey but assimilated more prey captured on coastal shelf waters. Isotopic differences between age classes
at Berlenga were much smaller and may have resulted from limited dietary segregation or from age-related metabolic differences.
The diet of shearwaters was also very different between the two colonies, with offshore pelagic prey only being detected at
Selvagem Grande. Our findings suggest that spatial foraging constraints influence resource partitioning between pelagic seabirds
and their offspring and can lead to a parent–offspring dietary segregation. 相似文献
27.
Vera S. Domingues Markos Alexandrou Vitor C. Almada D. Ross Robertson Alberto Brito Ricardo S. Santos Giacomo Bernardi 《Marine Biology》2008,154(3):465-474
The northeastern Atlantic and the Mediterranean Sea share geological histories and display great faunal affinities. The majority
of the Mediterranean species have Atlantic origins, with a few species with tropical affinities. These include the parrotfish
Sparisoma cretense and the wrasse Thalassoma pavo that are restricted to the subtropical northeastern Atlantic, the Macaronesian archipelagos (Azores, Madeira, and Canaries)
and the southern Mediterranean. The Pleistocene glaciations have been described as having different effects on the fauna of
the two regions. During glacial peaks, Mediterranean waters remained warmer than those of the adjacent Atlantic. Within the
eastern Atlantic, the effects of Pleistocene glaciations were differentiated. Here, we perform a comparative analysis focusing
on T. pavo and S. cretense populations from the northeastern Atlantic and the Mediterranean to assess the effects of Pleistocene glaciations in these
two species. Sequences from the mitochondrial control region were obtained and analyzed combining phylogeographic and demographic
approaches. Gene flow between Atlantic and Mediterranean populations was shown to be very high. The Mediterranean populations
of T. pavo and S. cretense showed high levels of genetic diversity, even in the eastern basin, pointing to an ancient colonization event. This suggests
that both species must have been able to persist in the Mediterranean during the cold Pleistocene periods. Historical migration
estimates revealed a Mediterranean towards Atlantic trend in the case of T. pavo, which may reflect the re-colonization of areas in the Atlantic by fish that survived the cold phases in relatively warmer
Mediterranean refugia. Our data also showed that within the Macaronesian Archipelagos, migrations occurred from Madeira towards
the Azores, for both T. pavo and S. cretense, thus supporting a post-glacial colonization of the Azores by fish that persisted in the warmer region of Madeira. Similar
geographic distributions, thermal affinities, and means of dispersion for T. pavo and S. cretense resulted in a similar response to the effects of Pleistocene glaciations, as evidenced by identical phylogeographic patterns. 相似文献
28.
José Cavalcante Souza Vieira Camila Pereira Braga Grasieli de Oliveira Aline de Lima Leite João Vitor de Queiroz Bruna Cavecci Alis Correia Bittarello Marília Afonso Rabelo Buzalaf Luiz Fabricio Zara Pedro de Magalhães Padilha 《Environmental Chemistry Letters》2017,15(4):717-724
Bioaccumulative metals such as mercury are found in increasing amounts in fish and their consumers. In the region of the Madeira River, in the Brazilian Amazon, mercury (Hg) is a predominant contaminant in the aquatic ecosystem. There is therefore a need to find specific biomarkers of mercury toxicity in fish to monitor contaminations. Here, mercury-bound proteins were identified in the liver tissues of fishes Mylossoma duriventre and Brachyplatystoma rousseauxii. Mercury was quantified in liver tissue, pellets and protein spots by graphite furnace atomic absorption. Proteins were fractionated by two-dimensional polyacrylamide gel electrophoresis and identified by mass spectrometry with electrospray ionization. We identified nine proteins linked to mercury and that presented biomarker characteristics of mercury. Among the proteins identified, isoforms of parvalbumin, ubiquitin-40S ribosomal protein S27a, brain-specific angiogenesis inhibitor 1-associated protein 2-like protein 2 and betaine–homocysteine S-methyltransferase 1 are notable for having the molecular function of binding to metallic ions. 相似文献
29.
Time Series Forecasting of Cyanobacteria Blooms in the Crestuma Reservoir (Douro River, Portugal) Using Artificial Neural Networks 总被引:2,自引:1,他引:1
In this work, time series neural networks were used to predict the occurrence of toxic cyanobacterial blooms in Crestuma Reservoir,
which is an important potable water supply for the Porto region, located in the north of Portugal. These models can potentially
be used to provide water treatment plant operators with an early warning for developing cyanobacteria blooms. Physical, chemical,
and biological parameters were collected at Crestuma Reservoir from 1999 to 2002. The data set was then divided into three
independent time series, each with a fortnightly periodicity. One training series was used to “teach” the neural networks
to predict results. Another series was used to verify the results, and to avoid over-fitting of the data. An additional independently
collected data series was then used to test the efficacy of the model for predicting the abundance of cyanobacteria. All of
the models tested in this study incorporated a prediction time (look-ahead parameter) equal to the sampling interval (two
weeks). Various lag periods, from 2 to 52 weeks, were also investigated. The best model produced in this study provided the
following correlations between the target and forecast values in the training, verification, and validation series: 1.000
(P = 0.000), 0.802 (P = 0.000), and 0.773 (P = 0.001), respectively. By applying this model to the three-year data set, we were able to predict fluctuations in cyanobacteria
abundance in the Crestuma Reservoir, with a high level of precision. By incorporating a lag-period of eight weeks, we were
able to detect secondary fluctuations in cyanobacterial abundance over the annual cycle. 相似文献
30.
Frederick Willem Bouckaert Yongping Wei James Pittock Vitor Vasconcelos Ray Ison 《Ambio》2022,51(8):1871
Successful river basin governance is challenged by actor engagement in the various stages of planning and management. A governance approach for determining priorities for actors for sustainable management was developed, based on a river basin diagnostic framework consisting of four social-institutional and four biophysical indicators. It was applied in river basins in Australia, Brazil, China and France. Actors diagnosed current and target capacity for these indicators, and estimated synergistic influences of interacting indicators. The results reveal different priorities and transformative pathways to achieve basin plan outcomes, specific to each basin and actor groups. Priorities include biodiversity for the Murray-Darling, local water management needs for the São Francisco and Yellow rivers, and improved decision-making for the Adour-Garonne. This novel approach challenges entrenched views about key issues and actor engagement roles in co-implementation of the basin plan under existing prevailing governance models, with implications for engagement and international collaboration on basin governance.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01699-4. 相似文献