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51.
The decline in the supply of natural resources is a cause for concern, especially given continued worldwide population growth. New habits and attitudes toward resource use are slowly being introduced into the everyday lives of persons residing in a number of countries. The term “ecological behavior” refers to acting in favor of the environment, whether these actions are voluntarily or not, or learned or not (Pato & Tamayo, 2006 ). The general objective of this study is to identify the environmental behavior—one of several terms used interchangeably with ecological behavior—of graduate students from a Brazilian federal institution of higher education. We chose this particular group because many of them already act, or will act, as professors. Thus, by virtue of their positions, they will function as opinion leaders who will influence the education of future professionals, establishing a chain through which shared values can gradually change the environmental behavior of society.  相似文献   
52.
Soil pollution with antimony is of increasing environmental concern worldwide. Measures for its control and to attenuate the risks posed to the ecosystem are required. In this study the application of several iron and aluminium oxides and oxyhydroxides as soil amendments was evaluated in order to assess their feasibility to stabilize Sb in mining polluted soils. Mine soils with different pollution levels were amended with either goethite, ferrihydrite or amorphous Al oxide at various ratios (0–10%). The effectiveness of such treatments was assessed by both batch and column leaching tests. The use of ferrihydrite or amorphous Al oxide proved to be highly effective to stabilize Sb. Immobilization levels of 100% were found when doses of 5% ferrihydrite or 10% amorphous Al oxide were applied, regardless of the soil Sb load. Column leaching studies also showed a high Sb leaching reduction (>75%) when soils were amended with 1% ferrihydrite or 5% amorphous Al oxide. Moreover, such treatments proved to simultaneously immobilize As and Pb in a great extent when soils were also polluted with such toxic elements.  相似文献   
53.
The effects of six clarification agents [egg albumin, blood albumin, bentonite + gelatine, charcoal, polyvinylpolypyrrolidine (PVPP) and silica gel] on the removal of residues of three fungicides (famoxadone, fluquinconazole and trifloxystrobin) applied directly to a racked red wine, elaborated from Monastrell variety grapes from the D.O. Region of Jumilla (Murcia, Spain) were studied. The clarified wines were filtered with 0.45 μ m nylon filters to determine the influence of this winemaking process in the disappearance of fungicide residues. Analytical determination of fluquinconazole and trifloxystrobin was performed by gas chromatography with electron captor detector (ECD), while that of famoxadone using an HPLC equipped with a diode array detector (DAD). Generally, trifloxystrobin is the fungicide that is the lowest persistent one in wines, except in the egg albumin study whereas, the most persistent one is fluquinconazole. The elimination depends on the nature of the active ingredient, though the water stability in the presence of light within it has more influence than the solubility and polarity of the product itself. The most effective clarifying agents were the charcoal and PVPP. The silica gel and bentonite plus gelatine were not enough to reduce considerably the residual contents in the wine clarified with them. In general terms, filtration is not an effective step in the elimination of wine residues. The greatest removal after filtration is obtained in wines clarified with egg albumine and bentonite plus gelatine, and the lowest in those clarified with PVPP.  相似文献   
54.
Wild polioviruses still remain endemic in three countries (Afghanistan, Pakistan, and Nigeria) and re-emergency of wild polio has been reported in previously polio-free countries. Environmental surveillance has been used as a supplementary tool in monitoring the circulation of wild poliovirus (PVs) and/or vaccine-derived PVs even in the absence of acute flaccid paralysis cases. This study aimed to monitor the presence of polioviruses in wastewater samples collected at one wastewater treatment plant located in the municipality of Rio de Janeiro, Brazil. From December 2011 to June 2012 and from September to December 2012, 31 samples were collected and processed. RD and L20B cell cultures were able to isolate PVs and non-polio enteroviruses in 27/31 samples. Polioviruses were isolated in eight samples (type 1 Sabin = 1, type 2 Sabin = 5, and type 3 Sabin = 2). Vaccine-derived polioviruses were not detected nor evidence of recombination with other PVs or non-polio enterovirus serotypes were observed among the isolates. The Sabin-related serotypes 2 and 3 presented nucleotide substitutions in positions associated with the neurovirulent phenotype at the 5′-UTR. Changes in important Amino acid residues at VP1 were also observed in the serotypes 2 and 3. Environmental surveillance has been used successfully in monitoring the circulation of PVs and non-polio enteroviruses and it is of crucial importance in the final stages of the WHO global polio eradication initiative. Our results show the continuous circulation of Sabin-like PVs and non-polio enteroviruses in the analyzed area during the study period.  相似文献   
55.
56.
Ovipositing adult females of myrmecophilous lycaenids are expected to select plants based on ant presence in order to maximize the survivorship of immature stages. Usually, larvae feed ants with honey-like solutions and, in turn, ants ward off parasitoids. Nonetheless, a rarely investigated approach is whether ant partners can also extend their protective behavior towards lycaenids eggs. Here, we investigated the ant-related oviposition pattern of Allosmaitia strophius and Rekoa marius; then, we compared egg parasitism according to the presence of ants. Lycaenid oviposition and egg parasitism (in percent) were experimentally compared in ant-present and ant-excluded treatments. The study plant, Heteropterys byrsonimifolia, is an extrafloral nectaried shrub which supports several ant species. We sampled 280 eggs, of which 39.65 % belonged to A. strophius and 60.35 % to R. marius. Both lycaenids eggs were significantly more abundant on branches with ants, especially those with Camponotus crassus and Camponotus blandus, two ant species known to attend to lycaenids. A. strophius and R. marius parasitism was 4.5- and 2.4-fold higher, respectively, in ant-present treatments, but the results were not statistically significant. Our study shows that ant-mediated host plant selection in lycaenids might be much more widespread than previously thought, and not restricted to obligate myrmecophilous species. Tending ants may be inefficient bodyguards of lycaenid eggs, because unlike larvae which release sugared liquids, eggs do not offer obvious rewards to ants. Ants can ward off parasitoids of larvae, as observed elsewhere, but our findings show that positive ant–lycaenid interactions are conditional and depend on immature ontogeny.  相似文献   
57.
In many bird species the cryptic winter plumage is due to the presence of light feather tips that conceal conspicuous colorations. The gradual abrasion of these tips that makes sexual traits visible has been interpreted as a strategy to improve mating success (here referred as the permanent exhibition hypothesis). However, under some circumstances, the maintenance of a full plumage that facultatively enables the bird to exhibit or cover aggression-inducing traits has proved to be advantageous (the coverable badge hypothesis). In a population of house sparrows where black throat patches (here called badges) are used in intrasexual competition, the degree of abrasion of dull feather tips that conceal bright colour early in the breeding season correlated neither with badge size nor with traits indicating morphology and body condition. These results are only in accordance with predictions of the coverable badge hypothesis. In 1992 experimental clipping of badge feather tips, which forced permanent exposure of badges, negatively affected birds with the largest badges in terms of nest acquisition, but an opposite trend was indicated for birds with the smallest badges. In 1993, when more novel birds in the study area were competing for nesting sites than in 1992, only badge size, but not the experimental manipulation, affected nesting success. These results suggest that the loss of the ability to conceal badges was disadvantageous, and more so if most competing individuals had already been resident in the colony in previous years and the larger their badges were. There is a striking contrast between the results reported for this study population, where badges mainly signal fighting ability, and those reported for another house sparrow population, where badges are mainly used in mate choice. In this last population, tip abrasion is advantageous for dominant individuals showing the largest badges. This suggests that the trade-off between conserving versus wearing off the feathers that conceal ornaments could have different optimal resolutions depending on the relative importance of inter and intrasexual selection on indicator traits. Received: 29 September 1995/Accepted after revision: 14 July 1996  相似文献   
58.
Management of coral reef resources is a challenging task, in many cases, because of the scarcity or inexistence of accurate sources of information and maps. Remote sensing is a not intrusive, but powerful tool, which has been successfully used for the assessment and mapping of natural resources in coral reef areas. In this study we utilized GIS to combine Landsat TM imagery, aerial photography, aerial video and a digital bathymetric model, to assess and to map submerged habitats for Alacranes reef, Yucatán, México. Our main goal was testing the potential of aerial video as the source of data to produce training areas for the supervised classification of Landsat TM imagery. Submerged habitats were ecologically characterized by using a hierarchical classification of field data. Habitats were identified on an overlaid image, consisting of the three types of remote sensing products and the bathymetric model. Pixels representing those habitats were selected as training areas by using GIS tools. Training areas were used to classify the Landsat TM bands 1, 2 and 3 and the bathymetric model by using a maximum likelihood algorithm. The resulting thematic map was compared against field data classification to improve habitats definition. Contextual editing and reclassification were used to obtain the final thematic map with an overall accuracy of 77%. Analysis of aerial video by a specialist in coral reef ecology was found to be a suitable source of information to produce training areas for the supervised classification of Landsat TM imagery in coral reefs at a coarse scale.  相似文献   
59.
The contribution of small watersheds to coastal pollution in Mediterranean areas is still poorly known, and presents great variations along an hydrological year. This work deals with the characterization and quantification of Al, Fe, Zn, Cu, Pb, Si, NO(3)(-) and organic carbon transported from the continent to the sea by a small coastal river in the French Mediterranean area. Transported species were characterized both during rainy and dry periods. During non-rainy periods (base-flow), waters showed a low content of contaminants, whereas during heavy rain events, following dry periods, some metals and organic carbon reached concentrations that could affect biological populations. These contaminants were mainly found in the particulate fraction, originating from the runoff of surface waters, which represents the main process of pollution in urban areas.  相似文献   
60.
Behavioral Ecology and Sociobiology - Consistent between-individual differences in behaviour, known as personality differences, are heritable and have consequences for individual survival and...  相似文献   
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