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11.
Gonçalo C. Cardoso Paulo Gama Mota Violaine Depraz 《Behavioral ecology and sociobiology》2007,61(9):1425-1436
We tested if male or female behavior towards manipulated song indicates intra- or inter-sexual selection of two characteristics
of serin song that are extreme and evolutionarily derived in this species: high frequency and fast syllable rate. In a first
experiment, we monitored vocal responses and attendance to song playbacks. Female behavior indicated a preference for high-frequency
song and suggested an aggressive function for fast syllable rates, as fast songs inhibited vocal response. Males did not show
discrimination of frequency or syllable rate with this experimental design. The second experiment used a simple approach/no
approach design, and in this experiment, males showed stronger discrimination between stimuli than did females. Therefore,
sex differences in discrimination appear not to result from differences in perceptual abilities but from differences in the
context of stimulus presentation. The second experiment also supported a role of song frequency in female choice, as the effect
of frequency was limited to females: males did not respond differently to song frequency and approached high-frequency songs
less than females did. Results of this experiment also supported an aggressive function for fast syllable rates, as the effect
of fast songs did extend to male behavior. Taken together, our results indicate that the high frequency and fast syllable
rate of serin song cannot result from a single selection process: while high frequency may have evolved by inter-sexual selection,
syllable rate provokes a pattern of response that is more consistent with intra-sexual selection. 相似文献
12.
E. E. G. Clavico G. Muricy B. A. P. da Gama D. Batista C. R. R. Ventura R. C. Pereira 《Marine Biology》2006,148(3):479-488
In the Brazilian coast, high numbers of the small brittle star Ophiactis savignyi usually live associated with the sponge Geodia corticostylifera (Demospongiae, Geodidae), but not with other sympatric sponge species. In order to check whether this association was related
only with the physical shelter provided by the sponge body or was chemically mediated, the crude organic extract of G. corticostylifera was added to sponge mimics made of phytagel and spongin skeleton. Control and treated mimics were simultaneously offered
to previously sponge-associated O. savignyi in both static seawater and flow-through laboratory experiments. Ophiuroids were allowed to move towards the preferred mimic.
The defensive properties of the sponge extract against fish predation and fouling were also evaluated. Chemotaxis assays showed
that symbiotic ophiuroids were able to chemically recognize its host sponge, moving significantly more towards mimics containing
G. corticostylifera extract. Chemical deterrence assays showed that the natural concentration of the extract of this sponge was also able to
inhibit generalist fish predation on field experiments and the attachment of the common mussel Perna perna in laboratory assays. These results indicate that the crude extract of G. corticostylifera plays multiple functions in the marine environment, presumably being responsible for a closer association of this sponge
with O. savignyi, providing protection for this ophiuroid and inhibition of epibionts on itself. 相似文献
13.
Yong Sheng Aleksey Benderev Donka Bukolska Kenneth Imo-Imo Eshiet Carlos Dinis da Gama Torsten Gorka Michael Green Nikolay Hristov Ismini Katsimpardi Thomas Kempka Jordan Kortenski Nikolaos Koukouzas Natalie Nakaten Vasilis Sarhosis Ralph Schlueter Vidal Navarro Torres Ana Carina Veríssimo Velemir Vesselinov Dongmin Yang 《Mitigation and Adaptation Strategies for Global Change》2016,21(4):595-627
This paper presents the outcome of a feasibility study on underground coal gasification (UCG) combined with direct carbon dioxide (CO2) capture and storage (CCS) at a selected site in Bulgaria with deep coal seams (>1,200 m). A series of state-of-the-art geological, geo-mechanical, hydrogeological and computational models supported by experimental tests and techno-economical assessments have been developed for the evaluation of UCG-CCS schemes. Research efforts have been focused on the development of site selection requirements for UCG-CCS, estimation of CO2 storage volumes, review of the practical engineering requirements for developing a commercial UCG-CCS storage site, consideration of drilling and completion issues, and assessments of economic feasibility and environmental impacts of the scheme. In addition, the risks of subsidence and groundwater contamination have been assessed in order to pave the way for a full-scale trial and commercial applications. The current research confirms that cleaner and cheaper energy with reduced emissions can be achieved and the economics are competitive in the future European energy market. However the current research has established that rigorous design and monitor schemes are essential for productivity and safety and the minimisation of the potential environmental impacts. A platform has been established serving to inform policy-makers and aiding strategies devised to alleviate local and global impacts on climate change, while ensuring that energy resources are optimally harnessed. 相似文献
14.
Gama Nuno Godinho Bruno Barros-Timmons Ana Ferreira Artur 《Journal of Polymers and the Environment》2022,30(1):194-205
Journal of Polymers and the Environment - Lignocellulosic composites are biodegradable, have low cost, neutrality to CO2 emission, easily processed, easily available and pause no health risks,... 相似文献
15.
Honscha Laiz Coutelle Penteado Julia Oliveira de Sá Gama Valério da Silva Bonifácio Alícia Aikawa Priscila dos Santos Marina Baisch Paulo Roberto Martins Muccillo-Baisch Ana Luíza da Silva Júnior Flavio Manoel Rodrigues 《Environmental science and pollution research international》2022,29(10):14176-14184
Environmental Science and Pollution Research - Coal exploration and burning activities are among the activities with the greatest potential to cause atmospheric pollution due to the combustion... 相似文献
16.
Lemos VA Novaes Gdos S de Carvalho AL Gama EM Santos AG 《Environmental monitoring and assessment》2009,148(1-4):245-253
A simple and sensitive method was developed for determination of trace copper by direct precipitation preconcentration and detection with Flame Atomic Absorption Spectrometry (FAAS). The reagent 2-[2'-(6-methyl-benzothiazolylazo)]-4-aminophenol (Me-BTAP) was used as precipitating agent. The experimental conditions for the quantitative precipitation of copper, such as pH, amount of reagents, temperature and the effect of diverse ions on the precipitation have been investigated. It was found that copper is quantitatively extracted (> or =95%) and the method provides a sensitivity enhancement of 40-fold for a 10 ml sample volume with a detection limit of 0.5 microg l(-1). The proposed method was successfully applied for the determination of trace copper in water, urine and biological samples. 相似文献
17.
Throughout this work PBDEs level determination in biota was developed for the first time in Portugal. The data obtained was important to provide a global perspective of Portugal contamination by PBDEs and allows the comparison with studies made in other countries. Environmental levels of fourteen polybrominated diphenyl ethers (PBDEs) were analysed in a number of biota samples (Barbus sp. and Mytilus galloprovincialis) taken over a large geographic range covering five rivers and coastal areas of Portugal. Tetrabromodiphenyl ether (BDE 47) was found in almost all samples ranging from not detected (nd) to 30ngg(-1) dry weight (dw). BDE 47 concentration is correlated with mussels weight indicating the bioaccumulation of this compound. Pentabromodiphenyl ethers (BDE 99 and BDE 100) were detected in several samples, but in lower concentrations. 相似文献
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19.
Yasmin Shirin Appelhans Mark Lenz Heloisa Elias Medeiros Bernardo Antonio Perez da Gama Renato Crespo Pereira Martin Wahl 《Marine Biology》2010,157(5):1151-1159
The production of defence metabolites is assumed to be costly in metabolic terms. If this holds true, low-light stress should
reduce the ability of seaweeds to defend themselves chemically against herbivory and fouling. We investigated the effect of
energy limitation on the defensive status of seaweeds by assessing their attractiveness to mesograzers and their activity
against a bivalve macrofouler in comparison with non-stressed conspecifics. The macroalgae Codium decorticatum (Woodw.) M. Howe, Osmundaria obtusiloba (C. Agardh) R. E. Norris, Pterocladiella capillacea (S. G. Gmel.) Santel. and Hommer., Sargassum vulgare C. Agardh and Stypopodium zonale (Lamour.) Papenf. collected at the southeastern Brazilian coast were exposed to six levels of irradiation (between 1 and
180 μmol photons m−2 s−1) for 10–14 days. After this period, algae from all treatment levels were: (a) processed as artificial food and offered to
an amphipod community dominated by Elasmopus brasiliensis Dana and (b) extracted to test for differences in settlement rates of the fouling mussel Perna perna L. on filter paper loaded with the crude extracts. Generally, photosynthesis rates and growth were reduced under low light
conditions. Attractiveness to herbivores and macrofoulers, however, was insensitive to energy limitation. We discuss possible
explanations for the observed absence of a relationship between light availability and algal defence including the change
in nutritional value of the algal tissue, the allocation of resources towards defence instead of growth and the absence of
costs for defence. 相似文献
20.
Environmental Economics and Policy Studies - This paper ranks two widely used command-and-control environmental instruments, in terms of relevant equilibrium variables such as output, profits,... 相似文献