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81.
Environmental Science and Pollution Research - Copper (Cu) is an extensively used heavy metal and an indispensible micronutrient for living beings. However, Cu is also toxic and exerts multiple...  相似文献   
82.
Returning honey bee foragers perform waggle dances to inform nestmate foragers about the presence, location and odour of profitable food sources and new nest sites. The aim of this study is to investigate how the characteristics of waggle dances for natural food sources and environmental factors affect dance follower behaviour. Because food source profitability tends to decrease with increasing foraging distance, we hypothesised that the attractiveness of a dance, measured as the number of dance followers and their attendance, decreases with increasing distance to the advertised food location. Additionally, we determined whether time of year and dance signal noise, quantified as the variation in waggle run direction and duration, affect dance follower behaviour. Our results suggest that bees follow fewer waggle runs as the food source distance increases, but that they invest more time in following each dance. This is because waggle run duration increases with increasing foraging distance. Followers responded to increased angular noise in dances indicating more distant food sources by following more waggle runs per dance than when angular noise was low. The number of dance followers per dancing bee was also affected by the time of year and varied among colonies. Our results provide evidence that both noise in the message, that is variation in the direction component, and the message itself, that is the distance of the advertised food location, affect dance following. These results indicate that dance followers may pay attention to the costs and benefits associated with using dance information.  相似文献   
83.
The effects of exposure of tilapia (Oreochromis mossambicus) to sublethal concentrations of lead on hematological and immunological parameters were investigated. The fish were semistatically exposed to low (L) (0.5 mg L?1), medium (M) (2.5 mg L?1), and high (H) (5 mg L?1) lead concentrations for 14 days. At the end of the trial, red blood cell (RBC) count, hematocrit (Hct) ratio and hemoglobin levels showed significant decreases in M and H groups, while RBC was significantly increased in L group compared to control group. Lysozyme activity showed a decrease in all groups on day 14 compared to control. A decrease in myeloperoxidase activity was seen in M and H groups on day 7, and in all treatment groups on day 14. In conclusion, it was found that exposure of O. mossambicus to lead concentrations affected hematological and immunogical parameters adversely.  相似文献   
84.
Ocean Afforestation, more precisely Ocean Macroalgal Afforestation (OMA), has the potential to reduce atmospheric carbon dioxide concentrations through expanding natural populations of macroalgae, which absorb carbon dioxide, then are harvested to produce biomethane and biocarbon dioxide via anaerobic digestion. The plant nutrients remaining after digestion are recycled to expand the algal forest and increase fish populations. A mass balance has been calculated from known data and applied to produce a life cycle assessment and economic analysis. This analysis shows the potential of Ocean Afforestation to produce 12 billion tons per year of biomethane while storing 19 billion tons of CO2 per year directly from biogas production, plus up to 34 billion tons per year from carbon capture of the biomethane combustion exhaust. These rates are based on macro-algae forests covering 9% of the world's ocean surface, which could produce sufficient biomethane to replace all of today's needs in fossil fuel energy, while removing 53 billion tons of CO2 per year from the atmosphere, restoring pre-industrial levels. This amount of biomass could also increase sustainable fish production to potentially provide 200 kg/yr/person for 10 billion people. Additional benefits are reduction in ocean acidification and increased ocean primary productivity and biodiversity.  相似文献   
85.
In the last few decades, metal oxide nanoparticles have shown impact in various areas, and such an impact causes an increased release in a different environment like soil, water, or air. A limited number of studies on soils showed that the biochemical parameters were affected by the metal oxide nanoparticles. However, the influence of metal oxide nanoparticles on soil elements has not been investigated. For this aim, zinc oxide nanoparticles were applied to two different soils; also, the effect of planting on soil elements was investigated via the cultivation of various plants roots (taproots, fibrous, bulb). Soils were treated with zinc oxide nanoparticles at 0, 1.0 and 20.0?mg during 4 weeks. Then, surface soil samples were collected and digested using an acid digestion procedure. Some biochemically important elements (Ca, Zn, Mg, Fe, Al, Cu, Co, Ni) were determined using a microwave plasma atomic emission spectrometer. The effect of time and dose-dependent zinc oxide nanoparticles on the element contents of different soils was investigated during planting, and the results were statistically evaluated.  相似文献   
86.
The mutagenic and carcinogenic effects of parathion-methyl were examined by bacterial reverse assay and a long term experiment with Wistar rats. The potential mutagenic effect of parathion-methyl in Salmonella typhimurium TA100 bacterial cells was observed without rat liver S9 metabolic activation. Parathion-methyl was further investigated for pathological changes in rat pancreas and liver. The long-term rat experiments showed that parathion-methyl exposure for 3 months can cause pathological changes in rat pancreases acinar cells and pancreatic hepatocytes. Atypical acinar cell focuses (AACF) were determined in the liver and pancreas of the rats. The results from short-term Ames test and long-term rat experiments suggest that parathion-methyl would be potential carcinogenic.  相似文献   
87.
The objectives of this study were to assess land suitability andto monitor the spatial and temporal changes in land use types (LUTs)by using GIS. The study was conducted in an irrigated area of 920ha, located in the East Mediterranean region of Turkey. Archiveddata of LUTs were utilized. Data analysis was conducted by usingArcInfo and ArcView GIS softwares. The land characteristics werecompared with land requirements of present LUTs by taking intoaccount the land evaluation results. Three major soil series andtwelve different LUTs were identified. Corn and citrus were themost planted LUTs in the assessment period. Generated mapsdemonstrated how LUTs changed spatially and temporally. Most LUTswere clustered in certain areas indicating that farmer'sselection of LUTs was affected by their habits and neighbor'sbehavior. Land suitability assessment results indicated thatCanakci and Mursel soil series were found to be highly suitable forall LUTs while Arikli soil series was determined to be moderately suitablecitrus, vegetables and watermelon. Citrus plantationmaps overlaid on soil series maps demonstrated that the citrushas not been planted completely on suitable areas. Landsuitability assessment showed that citrus plantation in Arikliseries would result in 40% yield loss and 58% of land is notused at its potential.  相似文献   
88.
By utilising a relatively underused framework developed by Maurie J. Cohen (1997. Risk society and ecological modernisation alternative visions for post-industrial nations. Futures, 29 (2), 105–119), this theoretical paper joins two of the most debated theories of environmental politics – ecological modernisation (EM) and Ulrich Beck’s risk society thesis – into a unified framework and problematises some of their implicit assumptions to theoretically introduce the notion of a “double-risk” society. In addition, it explains the differences between the traditional “Risk Society” theorised by the German sociologist Ulrich Beck and the newly introduced concept of a “double-risk” society. The arguments put forward in this paper provide some fresh perspectives facilitating the study of the techno-environmental risks and other ecological problems faced by “double-risk” societies. Theoretically, this paper adds to both EM theory and the risk society thesis as the generalisability of their existing versions is limited precisely because they fail to address some important social changes at the global structural level.  相似文献   
89.
Potable and equitable drinking water (DW) is a fundamental human right and essential for human health. This study is conducted to assess the groundwater and jar water quality of the roadside restaurants and tea stalls used for drinking by the local people around the Gazipur City area in Bangladesh. Water samples from 173 restaurants and tea stalls are collected. The physico-chemical and biological parameters are analyzed according to the guidelines and standards. The results illustrate that the color, EC, and Mn of 41%, 80%, and 62% of the samples, respectively, exceed the WHO and Environmental Conservation Rules (ECR) standards. In addition, E. coli and total coliform exceeding the threshold standards are found in 47% and 64% of the water samples, respectively. The contamination of DW by fecal coliforms is confirmed and supported by prior studies, which indicates that the DW supplied in restaurants and tea stalls are unsafe because of the possible presence of pathogens. These may cause potential health hazards to consumers from various water-borne diseases. Poor sanitation, unhygienic practices, and improper disposal of wastewater are responsible for the microbial contamination of DW. So, the authorities in charge of these places should take the right regulatory steps, such as regular sanitation inspections, DW quality monitoring, hand-washing practices, and better sanitation in these places.  相似文献   
90.
Considering successive and costly increases in electricity rates, this article evaluates the generation of electricity from a photovoltaic system using solar energy, a renewable source. The solar photovoltaic system is installed at UNIVATES University Center, a public university in the state of Rio Grande do Sul, Brazil, and it is also connected to the electrical grid. Data related to the climatic conditions of the location, such as incident solar radiation, rainfall, and mean temperature, were obtained during the system's evaluation period and used along with bibliographic research on similar systems installed in southern Brazil. Our study quantified the energy produced over one calendar year (2014) and related it to the climatic variables and the conversion efficiency achieved by the system's photovoltaic modules. Our results show that there is both a strong relationship between the production of energy and climatic conditions and that the city, Lajeado, and the Brazilian state of Rio Grande do Sul, have good potential to supply energy using photovoltaic systems connected to the electrical grid. The horizontal global solar radiation average obtained in the study location was 4.14 kilowatts per square meter per day (kWh/m2/day), and the average monthly production of energy reached 243.93 kWh/m2/month, with a total of 2,927.10 kWh produced in 2014, achieving a monthly average conversion efficiency of 11.07%. This conversion efficiency is close to the value of 12.6% obtained in 2013 in a similar study of the same solar photovoltaic system conducted over a shorter time period.  相似文献   
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