Nuptial coloration of red shiners (<Emphasis Type="Italic">Cyprinella lutrensis</Emphasis>) is more intense in turbid habitats

Communication is shaped and constrained by the signaling environment. In aquatic habitats, turbidity can reduce both the quantity and quality of ambient light and has been implicated in the breakdown of visual signaling. Here, we examined the relationship between turbidity (quantified with long-term data) and the expression of carotenoid-based nuptial coloration in the red shiner (Cyprinella lutrensis), a small-bodied cyprinid. Males in more turbid habitats displayed redder fins, and an experimental manipulation of adult diet suggested that carotenoid intake alone did not explain among-population color differences. These results run counter to similar studies where signal expression decreased in turbid conditions, and may be explained by the non-territorial red shiner mating system, interactions between the mechanism of coloration and the signaling environment, or reduced cost of color expression in turbid habitats (e.g., reduced predation risk). Our results highlight how the behavioral and ecological contexts in which signals function can shape evolutionary responses to the environment.     

Development,larvicide activity,and toxicity in nontarget species of the Croton linearis Jacq essential oil nanoemulsion

Environmental Science and Pollution Research - In this study, the essential oil (EO) from leaves of Croton linearis Jacq was extracted and characterized by GC/MS. The EO hydrophilic-lipophilic...     

Trace elements and microbiological parameters in farmed Nile tilapia with emphasis on muscle,water, sediment and feed

Fish may bioaccumulate contaminants from the aquatic environment and extend them to the food chain provoking risks to human health. This study evaluated the microbiological parameters of the pond´s water and trace elements concentrations in samples of water, sediment, feed and muscle of farmed Nile tilapia used for human consumption in southern Brazil. A total of 240 fish were collected from 12 tilapia farms. Sediment, tank water and dry ration used in the animals' diet were collected for analysis. Analysis were performed by Energy Dispersion X-ray Fluorescence (EDXRF), Inductively Coupled Plasma Mass Spectrometer (ICP-MS), Induced Coupled Plasma Optical Emission Spectrometer (ICP-OES), and Atomic Absorption Spectrometer (AAS-VGA). In addition, the microbiological analysis of the water was carried out. The concentrations of Se, I, Fe, Cu and Zn in fish muscle were higher than the recommended by the Brazilian legislation, considering the advised daily intake for adults. The arsenic element had concentrations above the limit stipulated by the present Brazilian legislation, observed in all samples of muscle, sediment and tank water highlighting a possible environmental and fish contamination by the toxic element. Moreover, the arsenic concentration in the water presented a positive correlation (ρ?=?0.33) with arsenic in the muscle, suggesting that tilapia is a good environmental bioindicator, once they properly reflect the levels of arsenic in the water. It is suggested to perform an arsenic speciation for quantification of the inorganic form and accurate assessment of the degree of toxicity in the muscle samples and risks it can bring to human health. Regarding the other potentially toxic elements (Hg, Pb and Cd), and microbiological analysis of water it was verified that the consumption of the fish in question does not raise risks, since the values are within a quality benchmark established by law. The concentration of total and fecal coliforms in pond´s water in the facilities was in agreement with the microbiological indexes required by the legislation of CONAMA class II. Western region presented the lowest concentrations of fecal coliforms when compared to the other regions. There was no significant difference in the microbiological counts of total heterotrophic bacteria, Vibrio spp. and Pseudomonas spp. among the regions.     

Accumulation, distribution and cellular partitioning of mercury in several halophytes of a contaminated salt marsh

This work evaluates the role of a plant community in mercury (Hg) stabilization and mobility in a contaminated Portuguese salt marsh. With this aim, the distribution of Hg in below and aboveground tissues, as well as the metal partitioning between cellular fractions (soluble and insoluble) in four different species (Triglochin maritima L., Juncus maritimus Lam, Sarcocornia perennis (Miller) A.J. Scott, and Halimione portulacoides (L.) Aellen) was assessed. Mercury accumulation, translocation and compartmentation between organs and cellular fractions were related to the plant species.Results showed that the degree of Hg absorption and retention was influenced both by environmental parameters and metal translocation/partitioning strategies. Different plant species presented different allocation patterns, with marked differences between monocots (T. maritima and J. maritimus) and dicots (S. perennis, H. portulacoides). Overall, the two monocots, in particular T. maritima showed higher Hg retention in the belowground organs whereas the dicots, particularly S. perennis presented a more pronounced translocation to the aboveground tissues. Considering cellular Hg partitioning, all species showed a higher Hg binding to cell walls and membranes rather than in the soluble fractions. This strategy can be related to the high degree of tolerance observed in the studied species. These results indicate that the composition of salt marsh plant communities can be very important in dictating the Hg mobility within the marsh ecosystem and in the rest of the aquatic system as well as providing important insights to future phytoremediation approaches in Hg contaminated salt marshes.     

Aerobic degradation of di- and trichlorobenzenes by two bacteria isolated from polluted tropical soils

Two polychlorinated biphenyl (PCBs)-degrading bacteria were isolated by traditional enrichment technique from electrical transformer fluid (Askarel)-contaminated soils in Lagos, Nigeria. They were classified and identified as Enterobacter sp. SA-2 and Pseudomonas sp. SA-6 on the basis of 16S rRNA gene analysis, in addition to standard cultural and biochemical techniques. The strains were able to grow extensively on dichloro- and trichlorobenzenes. Although they failed to grow on tetrachlorobenzenes, monochloro- and dichlorobenzoic acids, they were able to utilize all monochlorobiphenyls, and some dichlorobiphenyls as sole sources of carbon and energy. The effect of incubation with axenic cultures on the degradation of 0.9 mM 1,4-dichlorobenzene, 0.44 mM 1,2,3- and 0.43 mM 1,3,5-trichlorobenzene in mineral salts medium was studied. Approximately, 80-90% of these xenobiotics were degraded in 200 h, concomitant with cell increase of up to three orders of magnitude, while generation times ranged significantly (P<0.05) from 17-32 h. Catechol 1,2-dioxygenase and catechol 2,3-dioxygenase activities were detected in crude cell-free extracts of cultures pre-grown with benzoate, with the latter enzyme exhibiting a slightly higher activity (0.15-0.17 micromolmin(-1) mg of protein(-1)) with catechol, suggesting that the meta-cleavage pathway is the most readily available catabolic route in the SA strains. The wider substrate specificity of these tropical isolates may help in assessing natural detoxification processes and in designing bioremediation and bioaugmentation methods.     

Persistent organic pollutants in atmospheric deposition and biomonitoring with Tillandsia usneoides (L.) in an industrialized area in Rio de Janeiro state, southeast Brazil--Part II: PCB and PAH

Monitoring of immission of persistent organic pollutants in the industrialized area of Volta Redonda (V.R.) and in the National Park of Itatiaia (PNI) in southeast Brazil was performed using an endemic bromeliad species as biomonitor and measuring bulk deposition rates of polychlorinated biphenyls (PCB) and polycyclic aromatic hydrocarbons (PAH). For the sum of PCB, overall deposition rates were between 17 and 314 ng/(m2 day) in winter and between 43 and 81 ng/(m2 day) in summer, respectively. Deposition rates of dioxin-like PCBs ranged from 0.14 to 2.8 pg WHO-TEQ/(m2 day) in winter and from 0.90 to 4.3 pg WHO-TEQ/(m2 day) in summer. PCB deposition rates (total PCB and WHO-TEQ) were in the same range in winter in V.R. and PNI. In summer, contamination levels in V.R. were 6-10-folds higher than in PNI. PCB concentrations in biomonitor samples from V.R. and PNI were in the same range in summer and in winter. Concentrations of total PCB ranged from 14 to 95 microg/kg dry matter (d.m.) in winter and from 18 to 27 microg/kg d.m. in summer, respectively. The TEQ values were between 1.7 and 4.1 ng WHO-TEQ/kg d.m. in winter and between 1.9 and 2.9 ng WHO-TEQ/kg d.m. in summer. PCB concentrations of di-ortho PCB but not of non-ortho PCB were a factor of 2-4 lower in summer in both areas. PCB congener profiles resembled those from technical formulations. The profiles shifted to the higher chlorinated congeners in summer, probable due to revolatilisation of the lighter components at higher temperatures. PCB profiles in biomonitor resembled those from deposition samples and the shift to the heavier congeners in summer was even more pronounced. PAH deposition rates were in a similar range in both areas (131-2415 ng/(m2 day)). PAH levels in biomonitor samples from V.R. were about one order of magnitude higher than in samples from PNI indicating the impact of local sources. PAH profiles revealed stationary thermal processes as main source of contamination in V.R. whereas in PNI, biomass burning seems to be the main contamination source.     

Mercury uptake and allocation in Juncus maritimus: implications for phytoremediation and restoration of a mercury contaminated salt marsh

Juncus maritimus is the most abundant macrophyte in Laranjo bay, a Portuguese salt marsh heavily polluted by mercury (Hg). With the aim to elucidate the role of this species in the salt marsh Hg cycling and restoration, plants were harvested between March 2006 and January 2008 from four locations differing in Hg contamination. Metal uptake and distribution between plant organs were evaluated, biomass and Hg pools were also determined. Results showed that J. maritimus may influence the sediment pH and Eh, thus increasing the Hg available for uptake. Most (95-98%) of the absorbed Hg was retained belowground, phytostabilizing the metal and reducing the amount of Hg in the sediments. These results suggest that in salt marshes dominated by J. maritimus the approach could be phytostabilization, where these plants can be used to immobilize metals and store them belowground, reducing the pool of bioavailable Hg within contaminated marshes and acting as a sink rather than a source of contamination to the surrounding areas.     

Large and mesoscale meteo-oceanographic patterns in local responses of biogeochemical concentrations

Investigations surrounding the variability of productivity in upwelling regions are necessary for a better understanding the physical-biological coupling in these regions by monitoring systems of environmental impacts according to the needs of the regional coastal management. Using a spatial and temporal database from National Centers for Environmental Prediction (NCEP) and National Center for Atmospheric (NCAR) Research reanalysis, Quick Scatterometer vector wind, and surface stations from the Southeast coast of Brazil, we investigate the meteorological influences due to the large-scale systems in the variability of the nutrient and larvae concentration, and chlorophyll a, describing statistically relationships between them in upwelling regions. In addition, we used multivariate analysis, such as PCA and clustering to verify spatial and temporal variances and describe more clear the structure and composition of the ecosystem. Correlation matrix analyses were applied for different water masses present in the study area to identify the relations between physical and biogeochemical parameters in a region, where frequently upwelling occur. Statistical approaches and seasonal variability show that the period of November to March is more sensitive to nutrients (1.20?mg/m(3) for chlorophyll a, 2.20?μmol/l for total nitrogen and 5.5?ml/l for DO) and larvae concentrations (120 org/m(3) for most of the larvae, except for cirripedia that presented values around 370 org/m(3)) relating to the influence of large and mesoescale meteorological patterns. The spatial and temporal variables analyzed with multivariate approach show meaningful seasonality variance of the physical and biological samples, characterizing the principal components responsible for this variance in spring and summer (upwelling period), emphasizing the monitoring of species as crustaceans and mussels that are present in the local economy. Then, the spring and summer season are characterized by high productivity due to the occurrence of upwelling in this period.     

Changes in the trade in native medicinal plants in Brazilian public markets

Plants continue to be an important source of new bioactive substances. Brazil is one of the world’s mega-diverse countries, with 20 % of the world’s flora. However, the accelerated destruction of botanically rich ecosystems has contributed to a gradual loss of native medicinal species. In previous study, we have observed a fast and intensive change in trade of medicinal plants in an area of Amazon, where human occupation took place. In this study, we surveyed 15 public markets in different parts of Brazil in search of samples of 40 plants used in traditional medicine and present in first edition of Brazilian Official Pharmacopoeia (FBRAS), published in 1926. Samples of plants commercialized as the same vernacular name as in Pharmacopoeia were acquired and submitted to analysis for authentication. A total of 252 plant samples were purchased, but the laboratory analyses showed that only one-half of the samples (126, 50.2 %) were confirmed as the same plant species so named in FBRAS. The high number of unauthenticated samples demonstrates a loss of knowledge of the original native species. The proximity of the market from areas in which the plant occurs does not guarantee that trade of false samples occurs. The impact of the commerce of the substitute species on their conservation and in public health is worrying. Strategies are necessary to promote the better use and conservation of this rich heritage offered by Brazilian biodiversity.     

Impact of water quality on bacterioplankton assemblage along Cértima River Basin (central western Portugal) assessed by PCR–DGGE and multivariate analysis

The information on bacterial community composition (BCC) in Portuguese water bodies is very scarce. Cértima River (central western Portugal) is known to have high levels of pollution, namely organic. In the present work, the BCC from a set of 16 water samples collected from Cértima River Basin and its main tributaries was characterized using 16S rDNA–denaturing gradient gel electrophoresis, a culture-independent molecular approach. Molecular data were related to environmental parameters through multivariate analysis to investigate potential impact of water pollution along the river. Principal component analysis using environmental data showed a water quality gradient from more pristine waters (at the mountain tributaries) to waters with increasingly eutrophic potential (such as Fermentelos Lake). This gradient was mainly defined by factors such as organic and inorganic nutrient sources, electrical conductivity, hydrogen carbonate concentration, and pH. Molecular results showed variations in BCC along Cértima River Basin but in the main river section, a Bacteroidetes phylotype (Flavobacterium sp.) proved to be dominant throughout the river course. Multivariate analysis suggests that spatial variation of BCC along the Cértima River Basin depended mainly on parameters such as Chl a, total suspended solid (TSS), total organic carbon, electrical conductivity, and HCO _boxclose^-_{3}^{-} levels. Bacteroidetes phylotypes were all related to higher electrical conductivity and HCO₃^-_{3}^{-} levels although some of these were also correlated with high SO₄^2-_{4}^{2-} and others with high soluble reactive phosphorus, nitrate, TN, and Kjeld-N levels. The Gammaproteobacteria occurrence was correlated with high SO₄^2-_{4}^{2-} levels. One of the Betaproteobacteria phylotypes showed to correlate with low redox potential (E_h) and high temperature, pH, TSS, and Chl a levels while another one showed a negative correlation with Chl a values.