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81.
The present study provides a comprehensive analysis of the biochemical composition (proximate composition, amino acids and fatty acids in gonad, digestive gland and muscle) of the cirrate octopod, Opisthoteuthis calypso, collected off the coast of Portugal. Protein and energy contents of O. calypso were significantly lower (p < 0.05) than those observed for coastal octopods, suggesting that the gelatinous musculature of the cirrate octopus may not be a direct consequence of food limitation, but rather associated with reduced selective pressure for strong swimming ability in the deep sea. Moreover, principal component analyses of fatty acid (FA) data clearly separated coastal octopods from O. calypso. Saturated FA biomarkers (namely 16:0, 17:0, 18:0) and monounsaturated FA 22:1 suggest a higher phytodetrital influence on diet of O. calypso. A clear separation between groups was also observed with amino acid (AA) data. However, essential AA and non-essential AA designations (based on the flow of carbon through biochemical systems) do not necessarily provide an accurate picture of the origins of amino nitrogen in the deep-sea environment. Consequently, the interpretation of the present data is a challenging task but opens a new window of opportunity to unravel new trophic biomarkers in the deep sea.  相似文献   
82.
The threatened lizard Cnemidophorus littoralis occurs in only four restinga habitats of Brazilian coast and its current conservation status is “endangered”. Due to its restricted distribution, the effects of habitat degradation are especially harmful to them. To prevent a local or even total extinction, we analyzed changes in population density and in amount of disturbances of three restinga areas during a seven-year gap. This study took place in three restingas of Rio de Janeiro State, Brazil: Maricá, Jurubatiba and Grussaí. We compared C. littoralis current density with the one registered in 2005 by Menezes and Rocha (2013) with 2 ha transections in each restinga. We also made another group of transects to estimate population density along the entire extension of the restingas. Conservation index of each site was based on satellite images and field samplings. Data showed a decreasing trend of Cnemidophorus littoralis population density over the years. Grussaí had the lowest population density and the highest degradation index among the three sites, whereas Jurubatiba had the lowest degree of disturbance, the largest area and the highest lizard population density. Data showed an increase in the amount of disturbance in restingas over the years, which seemed to have a negative effect in C. littoralis population density. Improvement of surveillance and implementation of education programs in the protected areas and its surroundings, and periodic monitoring of C. littoralis populations to follow their density changes, are essential for the maintenance of the species.  相似文献   
83.
The winemaking process involves the generation of a significant amount of waste and wastewater. These residues should be addressed for recycling or treatment before being returned to environment. As each winery is unique in waste generation and disposal, plans for environmentally friendly waste management are not universal and should be tested for their effectiveness. In this study, a diagnostic was made during three years, in different wineries, throughout Portugal, in order to quantify and characterize the waste and the wastewater produced. The results showed that solid waste and wastewater are mainly produced during the harvest period, corresponding to 74% and 87%, respectively. One ton of processed grape approximately produce 0.13 t marc, 0.06 t lees, 0.03 t of stalks and 1.65 m3 of wastewater. No significant differences (P≤0.05) were observed for grape marc, lees and wastewater ratios, between years or wineries. With respect to the stalk ratio, there was no effect of year but the winery significantly affected this ratio (P≤0.05). During the study period the treated wastewater, since diluted, revealed suitable characteristics for irrigation representing an additional source of water. In this regard, the data acquisition and consolidation ensure the transfer of information and experience which constitute an essential step in a support decision tool design.  相似文献   
84.
This paper presents the study of the combustion of char residues produced during co-gasification of coal with pine with the aim of characterizing them for their potential use for energy. These residues are generally rich in carbon with the presence of other elements, with particular concern for heavy metals and pollutant precursors, depending on the original fuel used.The evaluation of environmental toxicity of the char residues was performed through application of different leaching tests (EN12457-2, US EPA-1311 TCLP and EA NEN 7371:2004). The results showed that the residues present quite low toxicity for some of pollutants. However, depending on the fuel used, possible presence of other pollutants may bring environmental risks.The utilization of these char residues for energy was in this study evaluated, by burning them as a first step pre-treatment prior to landfilling. The thermo-gravimetric analysis and ash fusibility studies revealed an adequate thermochemical behavior, without presenting any major operational risks.Fluidized bed combustion was applied to char residues. Above 700 °C, very high carbon conversion ratios were obtained and it seemed that the thermal oxidation of char residues was easier than that of the coals. It was found that the char tendency for releasing SO2 during its oxidation was lower than for the parent coal, while for NOX emissions, the trend was observed to increase NOX formation. However, for both pollutants the same control techniques might be applied during char combustion, as for coal. Furthermore, the leachability of ashes resulting from the combustion of char residues appeared to be lower than those produced from direct coal combustion.  相似文献   
85.
A method to determine the optimal subset of stations from a reference level groundwater monitoring network is proposed. The method considers the redundancy of data from historical time series, the times associated with the total distance required to run through the entire monitoring network, and the sum of the times for each monitoring station. The method was applied to a hypothetical case-study consisting of a monitoring network with 32 stations. Cost-benefit analysis was performed to determine the number of stations to include in the new design versus loss of information. This optimisation problem was solved with simulated annealing. Results showed that the relative reduction in exploration costs more than compensates for the relative loss in data representativeness.  相似文献   
86.
Artisanal small-scale gold miners (ASM) occasionally employ whole ore amalgamation by adding mercury into ball mills to recover gold. In this process, 25–30% of the mercury added is lost to the environment. It is also inefficient less than 30% of gold is recovered. Amalgamation, followed by cyanidation, has been observed at many artisanal mining sites. This combination poses additional environmental and health consequences. Tests with ore samples from Talawaan, North Sulawesi, Indonesia indicate the possibility of replacing mercury by cyanidation in the ball mill, reaching gold extraction of 93% in 6 h of leaching. The gold in the Indonesian ore sample is fine and less than 8% of gold recovery was obtained with gravity concentration of the ore ground 80% below 0.25 mm, which is a reasonably fine grain size for artisanal gold operations. Replacing mercury addition with cyanidation in ball mills was implemented in one artisanal gold mining operation in Portovelo, Ecuador, achieving 95% of gold extraction in 8 h of mill leaching. This technique demonstrated a drastic improvement in gold recovery. It was found to be a simple, inexpensive technique well accepted by local miners. The results from laboratory and field tests are promising; however a thorough investigation into the socio-economic and environmental aspects of this presented alternative must be conducted prior to introduction.  相似文献   
87.
Environmental Science and Pollution Research - The application of sewage sludge (SS) in the soil can be a valuable way to increase its content of organic matter. However, the concentration of...  相似文献   
88.
We investigate team member feelings of collective psychological ownership (CPO) over teamwork products, the psychological paths that lead to it, and its impact on team workers' evaluations of team effectiveness, turnover intentions, and intentions to champion teamwork products. We focus on the teamwork product as an important target of ownership feelings, building on theories of self-extension, psychological ownership, and team emergent states. In Study 1, we validate measures for three ownership activating experiences (OAE) that have been proposed as paths to CPO (control over, intimate knowledge regarding, and investment in the teamwork product) using two samples of individual team workers (n = 210 and n = 140). In Study 2 (n = 183) and Study 3 (n = 200), we use surveys and a multiwave design to show that team workers' feelings of CPO mediate the relationship between investment in and intimate knowledge regarding the product and team effectiveness evaluations, team turnover intentions, and intentions to champion the work product. In Study 4 (n = 48 teams), CPO was predicted by the ownership activating experiences, at the team level. This research additionally highlights the benefits to organizations of creating conditions for the emergence of employee feelings of shared ownership over teamwork products.  相似文献   
89.
90.
The effects of the nitrofuran furaltadone on Ulva lactuca   总被引:1,自引:0,他引:1  
The use of pharmaceuticals in the food production industry as prophylatic and therapeutic agents is necessary to promote animal health, but may entail significant consequences to natural ecosystems, especially in the cases of overdosing and use of banned pharmaceuticals. The vast effects that antibiotics released into the environment have on non-target organisms are already under the scope of researchers but little attention has been given to primary producers such as macroalgae. The present study assessed furaltadone’s, an antibacterial agent illegally used for veterinary purposes, uptake capacity by Ulva lactuca and its effect in the growth of this cosmopolitan macroalgae. Differences in macroalgal growth were shown when submitted to prophylactic and therapeutic concentrations of furaltadone in the water (16 and 32 μg mL−1, respectively). The therapeutic concentration caused higher growth impairment than the prophylactic treatment did, with 87.5% and 58% reductions respectively. Furthermore, together with data collected from the accumulation assays, with values of internal concentrations as high as 18.84 μg g−1 WW, suggest that the macroalgae U. lactuca should be included in field surveys as a biomonitor for the detection of nitrofurans.  相似文献   
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