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991.
The ultimate and proximate causes of natal dispersal have been extensively investigated, but the behaviour of dispersers in
relation to social interactions has been largely neglected. Here, we investigated the social organisation of floating individuals
during their dispersal by analysing the behaviour of 40 radio-tagged eagle owls Bubo bubo during the wandering and stop phases of dispersal. Unexpectedly, eagle owl floaters mixed with conspecifics independently
of their sex, age, phase of dispersal, birthplace, health status and habitat features, showing an ‘underworld’ of interactions
characterised by the absence of obvious social organisation or short-term strategies. Non-breeding owls were not transient
floaters that occurred at numerous sites for short periods of time but rather had fairly stable home ranges: they attempted
to settle as soon as possible within well-defined home ranges. The spatial distribution pattern of floaters and high rates
of home range overlap support the prediction that floating individuals are not spatially segregated, challenging the expectation
that dominance by size, age and/or health status may determine the exclusive use of some portions of the dispersal area. Finally,
(1) the short distances among conspecifics and the extensive home range overlaps allowed us to discard the possibility that
neighbouring floaters represent a real cost during dispersal and (2) floater interactions showed a lack of clear mechanisms
for avoidance of kin competition among offspring or inbreeding. 相似文献
992.
Jesús Ambrosio-Martin María José Fabra Amparo López-Rubio Giuliana Gorrasi Andrea Sorrentino Jose M. Lagaron 《Journal of Polymers and the Environment》2016,24(3):241-254
The aim of this study was the assessment of high energy ball milling technique to develop poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) nanocomposites containing bacterial cellulose nanowhiskers (BCNW). Crystallization behaviour of PHBV/BCNW nanocomposites was studied under non-isothermal and isothermal conditions using differential scanning calorimetry. The changes in PHBV crystalline structure were also studied using X-ray diffraction. The results confirmed that BCNW acted as nucleating agents and, hence, favored the crystallization of the PHBV. The oxygen permeability of the nanocomposites was reduced by ~22 % when compared to that of the neat PHBV. This work provides a new insight into the development of polyhydroxyalkanoate composites by means of the high energy ball milling technique. 相似文献
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996.
Valeria Andreotti Anuta Chindris Gianni Brundu Dario Vallainc Matteo Francavilla Joan García 《Chemistry and Ecology》2017,33(8):750-761
Current aquaculture practices have a detrimental impact on the environment, in particular due to the release of high concentration of nitrogen and phosphorus that can induce eutrophication. This study investigates and compares the capacity of three microalgae species Tetraselmis suecica, Isochrysis galbana and Dunaliella tertiolecta, in the bioremediation of grey mullet Mugil cephalus wastewater. The experiment was conducted in batch conditions for 7 days using completely mixed bubble column photobioreactors. After two days, T. suecica and D. tertiolecta were able to remove more than 90% of dissolved inorganic nitrogen (DIN) and dissolved inorganic phosphorous (DIP), whereas I. galbana removed only 32% and 79% of DIN and DIP, respectively. A higher biomass yield resulted for T. suecica (603?±?34?mg/L, mean?±?SE). This study confirms the potential to employ T. suecica in an Integrated Multi-Trophic Aquaculture system for bioremediation of wastewater and identifies D. tertiolecta as another valid candidate species. Moreover, these species can growth in unsterilized culture media, and this reduces energy consumption, costs and efforts. 相似文献
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Ivanović Jelena Janjić Jelena Baltić Milan Milanov Raša Bošković Marija Marković Radmila V. Glamočlija Nataša 《Environmental science and pollution research international》2016,23(17):17105-17112
Environmental Science and Pollution Research - The aim of this study was to investigate the presence of metal contamination in water, sediments and three different fish species. All samples were... 相似文献
999.
María Oliveira Rosa M. Crujeiras Alberto Rodríguez-Casal 《Environmental and Ecological Statistics》2014,21(1):143-159
Smoothing methods and SiZer (SIgnificant ZERo crossing of the derivatives) are useful tools for exploring significant underlying structures in data samples. An extension of SiZer to circular data, namely CircSiZer, is introduced. Based on scale-space ideas, CircSiZer presents a graphical device to assess which observed features are statistically significant, both for density and regression analysis with circular data. The method is intended for analyzing the behavior of wind direction in the atlantic coast of Galicia (NW Spain) and how it has an influence over wind speed. The performance of CircSiZer is also checked with some simulated examples. 相似文献
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