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Correction to: A Review of the Techniques Used to Control Confounding Bias and How Spatiotemporal Variation Can Be Controlled in Environmental Impact Studies Полный текст
2020
Hatami, Rezvan
Unfortunately, the Figure 1b was incorrectly captured in the published online paper.
Показать больше [+] Меньше [-]Driving forces of China’s multisector CO2 emissions: a Log-Mean Divisia Index decomposition Полный текст
2020
Pan, Wei | Tu, Haiting | Hu, Zheng | Pan, Wulin
To figure out which factor contributes more on carbon emissions caused by energy consumption, this research took multisector analysis based on the Log-Mean Divisia Index Method (LMDI) and decoupling theory to assess the driving factors of carbon dioxide (CO₂) emissions in China’s six sectors from 2003 to 2016. Our empirical results reveal that China’s economy can be divided as three decoupling stages and exhibited a distinct tendency toward strong decoupling with a turning point in 2008. Thus, we discuss the impact of 2008 economic crisis on carbon emissions based on decomposition results. The empirical results of our study show the following five conclusions. (1) Most sectors in China are in weak decoupling state due to the inhibition of energy intensity on carbon emissions. (2) Different factors contribute differently to reducing emissions in different sectors, economic output has the most prominent effect, followed by energy intensity and population scale. (3) China’s current carbon emission reduction measures benefit more on energy efficiency. (4) The economic crisis has greatly reduced energy efficiency and has no significant impact on other factors. (5) If all industries adjust their energy mix, carbon emissions in China can be reduced by almost 17% every year.
Показать больше [+] Меньше [-]Effect of composted organic amendments and zinc oxide nanoparticles on growth and cadmium accumulation by wheat; a life cycle study Полный текст
2020
Bashir, Arooj | Rizwan, Muhammad | Ali, Shafaqat | Adrees, Muhammad | Rehman, Muhammad Zia ur | Qayyum, Muhammad Farooq
Cadmium (Cd) availability in arable soils is a serious issue while little is known about the role of co-composted organic amendments and zinc oxide nanoparticles (ZnO-NPs) foliar spray on biomass and Cd accumulation in wheat grains. The current study investigated the soil application of organic amendment (composted biochar and farmyard manure) at a level of 0, 1, and 2% w/w and foliar spray of ZnO-NPs (0, 100, and 200 mg/L) on biomass, yield, and Cd in wheat grains cultivated in an aged Cd-contaminated agricultural soil. The results indicated that organic amendment increased the biomass, chlorophyll concentrations, yield, and activities of peroxidase and superoxide dismutase of wheat while decreased the electrolyte leakage and Cd concentrations in different parts of wheat such as shoots, roots, husks, and grains. This effect of organic amendment was further enhanced by the foliar spray of ZnO-NPs in a dose-additive manner. Cadmium concentration in grains was below threshold level (0.2 mg/kg DW) for cereals in combined application of 200 mg/L ZnO-NPs and 1% organic amendment as well as in higher treatment (2%) of organic amendment and NPs. Thus, combined use of organic materials and NPs might be a suitable way of reducing Cd and probably other toxic trace element concentrations in wheat and other cereals.
Показать больше [+] Меньше [-]Considering environmental variables in the design of waste dumpsites Полный текст
2020
Fernando, Machuca Pérez | Claudio, Arellano Vergara
Mining generates a significant quantity of waste material including ballast, gravel, and slags, which are often deposited in areas without taking into account the environment impacts and the need to ensure the physical and chemical stability of the disposed waste. One of the less studied problems is the emission of particulate matter produced by wind erosion at the dumpsites. This erosion is mainly caused by two factors, wind speed and turbulence, due to surface phenomenon. Until now, the design of waste dumpsites in the Chilean mining industry has not considered these environmental conditions. Efforts to minimize disposal costs have always been achieved by depositing ballast without considering these variables. When wind impacts this unprotected surface, it creates a source of dust that requires some special attention. The problem that this research tries to solve is to reduce particulate material to the atmosphere from waste dumps in which, under certain atmospherics and geographic conditions, specifically on winter season, its concentrations overpass the maximum limit allowed by law, generating bronchopulmonary diseases and even closing partially or totally mine operation. The result is the creation of a waste dumpsite design model, with its corresponding algorithms, which will allow optimization of the waste dumpsite design. From these results, future researches could explore more sustainable mining, such as unit operations, drilling, blasting, load and crushing material, reducing particulate material emissions to the atmosphere, and minimizing environmental impact due to exploitation.
Показать больше [+] Меньше [-]Use of a broad β-diversity measure of pelagic ciliate communities for assessing vertical heterogeneity of water columns in the Pacific Arctic Ocean Полный текст
2020
Xu, Guangjian | Yang, Eun Jin | Lee, Youngju | Kang, Sung-Ho
Multivariate dispersion has proven to be a broad β-diversity measure that shows the heterogeneity of environmental conditions. The dispersion patterns of pelagic ciliate communities were investigated at eight water depths in the northern Bering Sea of the western Arctic Ocean and Chukchi Sea. Multivariate analysis indicated that (1) pelagic ciliates showed significant variability in multivariate dispersion on a vertical scale, (2) dispersion patterns were shaped by both the species composition and individual abundance, (3) vertical variation in species occurrence was significantly related to nutrients and chlorophyll a, and (4) the dispersion measures at both species occurrence and species abundance resolutions were significantly negatively related to salinity and dissolved oxygen. This suggests that multivariate dispersion measures driven by both species composition and the individual abundance of pelagic ciliates may be a useful indicator of environmental heterogeneity in marine ecosystems.
Показать больше [+] Меньше [-]System Dynamics Modelling of the Global Extraction, Supply, Price, Reserves, Resources and Environmental Losses of Mercury Полный текст
2020
Sverdrup, Harald Ulrik | Olafsdottir, Anna Hulda
How mercury flows from geological sources to society and to the environment was modelled for this study. The industrial dynamics of mercury was modelled and included in the integrated assessment model WORLD7. The simulated mercury losses were used as input for a simplified global model for environmental pollution. The outputs were analysed and used to assess mercury pollution amounts and supply to society. In fossil fuels, there are a potential stock of 2 million tons in coal and other hydrocarbons, and 450,000 tons of that could be released to the environment if the fossil fuels are all to be burned. Such release would potentially cause major environmental damage and a significant human health risk. The simulations suggest that environmental mercury flows may peak in 2025, and slowly decline as mercury gets immobilized in nature. The simulations show that the pollution from technical use is eliminated by putting the 2013 Minimata Convention into effect, but that environmental pollution from fossil fuels combustion and from environmental re-emissions will remain a significant problem for the next decades.
Показать больше [+] Меньше [-]Physiological and Biochemical Response of a Hot-Spring Cyanobacterium Nostoc Sp. Strain HKAR-2 to Aluminum Toxicity Полный текст
2020
Kannaujiya, Vinod K. | Kumar, Deepak | Pathak, Jainendra | Rajneesh, | Sinha, Rajeshwar P.
Aluminum is an undesirable water pollutant released by water treatment plants and metal processing industries that exhibit enormous toxic effects on water bodies. In the present study, we have investigated the effects of aluminum toxicity on the physiological and biochemical behavior of a hot-spring cyanobacterium Nostoc sp. strain HKAR-2. The growth of cyanobacterium was declined up to 33% by increasing aluminum concentration from 0.2 to 0.6 mM at pH 7.5 as compared to control (non-treated). However, the growth had further declined up to 87 and 92% by decreasing the pH to 6.0 and 5.0, respectively, as compared to control (pH 7.5) after 12 days of treatment. The amount of protein, chlorophyll, mycosporine-like amino acids, phycobiliproteins, extracellular and intracellular macronutrients such as phosphate and nitrate contents, and nitrate reductase activity was also declined at pH 7.5 as compared to non-treated control. In addition, aluminum also altered the sodium and potassium ions in both extracellular and intracellular environments. There was an increase in the activity of antioxidative enzymes such as catalase (CAT), superoxide dismutase (SOD), and ascorbic peroxidase (APX) ranging from 58, 79, and 40%, respectively, at 0.6 mM aluminum. The increase in intracellular concentration of aluminum was directly proportional to the inhibition of cyanobacterial growth at pH 7.5. In conclusion, aluminum showed acute toxicity on the hot-spring cyanobacterium Nostoc sp. strain HKAR-2, which indicates that aluminum may adversely affect the microbiota of hot-spring habitats.
Показать больше [+] Меньше [-]Development of an on-site early warning water quality monitoring system for pesticide detection by absorption and photo-induced fluorescence Полный текст
2020
Bakhoum, Jean-Pierre | Diop, Ndeye A. | Bodian, El Hadji T. | Mbaye, Olivier M. A. | Diaw, Pape. A. | Cissé, Lamine | Gaye-Seye, Mame D. | Thiare, Diene D. | Coly, Atanasse | Le Jeune, Bernard | Giamarchi, Philippe
This paper describes prototypes of an on-site early warning water quality monitoring system (EWWQMS) for pesticide quantification in natural waters by fluorescence and absorbance. As many pesticides are not naturally fluorescent, this EWWQMS uses UV irradiation to transform these compounds into highly fluorescent photoproducts and obtain sufficient sensitivity. To obtain a better specificity, the system uses four UV LEDs at different wavelengths to excite the fluorescent photoproducts. For pesticides that are not sensitive to photoconversion, the EWWQMS prototypes also use UV absorption for their quantification, thus offering a wider application range. A first system uses a diode array spectrometer for detection. A second system uses a higher resolution spectrometer and an intensified CCD camera detection to increase sensitivity. Analytical applications were conducted for the determination of fipronil, acetamipride, cyprodinil, trifluraline and pendimethaline in water using both the EWWQMS prototypes. The analytical performances of these new systems are good compared with other photo-induced fluorescence methods already published. Limits of detection without pre-concentration are in the range of 0.2 to 3 ng mL⁻¹ and the recovery values range from 95 to 108%. These results show that the EWWQMS prototypes can be used as an alert system to protect industrial plants from pesticide contaminations that exceed the capabilities of their cleaning processes.
Показать больше [+] Меньше [-]Raising the water temperature: consequences in behavior and biochemical biomarkers of the freshwater crab Aegla longirostri (Crustacea, Anomura) Полный текст
2020
Cerezer, Cristina | Leitemperger, Jossiele Wesz | do Amaral, Aline Monique Blank | Ferreira, Bruna Ceretta | Marins, Aline Teixeira | Loro, Vania Lucia | Bartholomei-Santos, Marlise Ladvocat | Santos, Sandro
Understanding how temperature alone affects biomarkers commonly used in ecotoxicology studies and biomonitoring programs is important to obtain a more real response in field studies, especially in freshwater. Thus, we analyzed the behavioral responses, the lethality, and the biochemical biomarkers in the freshwater crustacean Aegla longirostri at different water temperatures. Animals were exposed under laboratory conditions, to 18 °C, 21 °C, 24 °C, and 26 °C for 48 h. There were significant changes in biochemical parameters in different tissues (hepatopancreas, gills, and muscle) and in the behavioral tests in A. longirostri. Hepatopancreas was especially affected by the elevation of temperature, as showed by the high levels of carbonyl proteins. The activity of acetylcholinesterase increased in a temperature-dependent manner in muscle. Glutathione S-transferase activity decreased with the elevation of temperature in all tissues sampled. The results obtained in this study indicate that when assessing the health of polluted limnic ecosystems through the use of organisms in situ, the intrinsic effect of abiotic factors, such as temperature, on biomarkers must be considered.
Показать больше [+] Меньше [-]Ecological risk assessment of heavy metals to aquatic organisms in the Lhasa River, Tibet, China Полный текст
2020
Mao, Guozhu | Zhang, Yu | Tong, Yindong | Huang, Xiang | Mehr, Faryal
The Lhasa River is the largest and most important tributary of the Yarlung Tsangpo River on the Tibetan Plateau, China. It is an important source of drinking water and irrigation for the inhabitants living in the watershed. Despite the increasing focus on water chemistry, the ecological risk assessment (ERA) caused by heavy metals to aquatic organisms in the Lhasa River has not been performed before. Based on the documented monitoring data for heavy metals, the species sensitivity distributions (SSDs) method was applied in this study. The potential ecological risks induced by eight major heavy metals (including arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), mercury (Hg), manganese (Mn), lead (Pb), and zinc (Zn)) in the Lhasa River to four typical categories of freshwater organisms, including insects, crustaceans, fish, and mollusks, were assessed in different water periods (e.g., high, normal, and low water-periods). Results suggested that the downstream part of the Lhasa River and the Meldromarchu and Tölungchu tributaries are the principal zones for the high aquatic ecological risks. For most of the monitoring sites, the ecological risks decreased in the following order: high-water period > normal-water period > low-water period. During the high-water period, Cu had the highest ecological risks for all selected species. For the insects, the ecological risks were quite low (< 1%) throughout the year. These results suggested that particular attention should be paid to the contamination of certain heavy metals (e.g., Cu and Cr) in the future water management in the Lhasa River.
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