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A comparative study of trace elements in Cymodocea nodosa from three semi-enclosed coastal areas in Tunisia Full text
2019
Zakhama-Sraieb, Rym | Zribi, Imen | Mnasri, Intissar | Charfi-Cheikhrouha, Faouzia
The present study quantifies the levels of five trace elements (TEs) Zn, Cu, Ni, Pb, and Cd in the leaves and rhizomes of Cymodocea nodosa as well as the surficial sediments from three semi-enclosed coastal areas in Tunisia, in the south Mediterranean Sea. Samples were taken from the Bizerte and Ghar El Melh lagoons and from marina Cap Monastir. The TE ranking was found to be Zn > Cu > Pb > Ni > Cd in sediments and Zn > Cu = Ni = Pb = Cd in C. nodosa leaves and rhizomes. Except for Ni, levels of Zn, Cu, Pb, and Cd significantly differed between the sites. Translocation factors (TFs) were > 1 for all trace elements proving the high capacity of C. nodosa to accumulate TEs in its above-ground tissues. Results show that marina Cap Monastir’s meadow exhibits higher TFs than the Bizerte and Ghar El Melh lagoons. This can be due to the presence of the non-indigenous species Halophila stipulacea. The present study highlights the need for further investigation on the effect of interspecific interaction on TE uptake by seagrasses.
Show more [+] Less [-]Distribution of heavy metal and macroelements of Indian and imported cigarette brands in Turkey Full text
2019
Özcan, Mehmet Musa | Aljuhaimi, Fahad | Uslu, Nurhan | Ghafoor, Kashif | Mohamed Ahmed, Isam A. | Babiker, Elfadıl E.
While Cd contents of cigarettes are determined between 0.44 (C8) and 1.55 mg/kg (C7), Co contents of cigarette samples varied between 0.26 (B5) and 2.19 mg/kg (B3). Also, while Cr contents of tested cigarettes are determined between 0.88 mg/kg (C5) and 1.72 mg/kg (B2), Mo contents of cigarettes ranged from 0.39 (C7) to 1.13 mg/kg (B2). In addition, Cu contents of cigarettes varied between 10.36 (C11) and 30.47 mg/kg (C18), while Fe contents of cigarette samples range between 306.03 (C5) and 595.42 mg/kg (C16). In addition, while Ni contents of cigarettes vary between 1.00 (C7) and 3.17 mg/kg (C1), Pb contents of brands varied between 0.16 (B4) and 7.37 mg/kg (B1). In general, Indian and imported cigarette samples used in Turkey are rich in Ca, K, Mg, P, and S. In Indian samples, B4 and B5 cigarette samples contained lower heavy metals compared with other cigarettes.
Show more [+] Less [-]Engine parameter optimization of palm oil biodiesel as alternate fuel in CI engine Full text
2019
Kumar, Akula Naresh | Kishore, Pisipaty Srinivas | Raju, Kalidindi Brahma | Kasianantham, Nanthagopal | Bragadeshwaran, Ashok
Stringent emission regulations and depletion of crude oil are driving researchers toward alternative fuels. In this context, palm oil emerges as a good competitor as it is highly economical compared to other alternative fuels. The current research work centers around the impact of palm oil methyl ester on performance, combustion, and emission characteristics at varying injection timings and exhaust gas recirculation rates. In the first phase of this research work, various blends of palm oil methyl ester with diesel with volume concentrations of 10, 20, and 30% were prepared and tested at different load conditions. Injection timing was then varied for the optimized blend. In the second phase, the impact of exhaust gas blending with fresh charge was studied at optimized injection timing. The test outcomes revealed that 20% mix of palm oil at 27° bTDC with exhaust gas blending of 20% generated higher brake thermal efficiency, higher peak pressure, and less hydrocarbon and nitrogen oxide emissions compared to diesel at standard injection timing of 23° bTDC and no blending of exhaust gases with fresh charge. However, progression of injection timing with 20% exhaust gas mixing indicated a slight penalty in smoke discharges. Brake thermal efficiency at advanced injection timing with 20% mix of exhaust gases reduced by 7.7% for diesel and increased by 6.5% for 20% blend of palm oil when compared to standard injection timing of diesel and no blending of exhaust gases. Significant diminishments in oxides of nitrogen (lessened by 6.6%) and hydrocarbons (decreased by 30.43%) have been noted for 20% mix of biodiesel at advanced injection timing with 20% exhaust gas mix contrasted to diesel at standard conditions. Therefore, the present examination prescribes 20% merging of exhaust gases for 20% blend of palm oil with advancement of injection timing for diesel engine applications.
Show more [+] Less [-]Potential of indigenous plant species for phytoremediation of metal(loid)-contaminated soil in the Baoshan mining area, China Full text
2019
Pan-Pan, | Lei, Mei | Qiao, Pengwei | Zhou, Guangdong | Wan, Xiaoming | Chen, Tongbin
A field survey was conducted to investigate metal(loid) concentration in soils and native plants in the Baoshan mining area for potential application in phytoremediation. Total concentrations of arsenic (As), cadmium (Cd), lead (Pb), and zinc (Zn) in soil varied from 125 to 6656, 5.10 to 1061, 568 to 49294, and 241 to 17296 mg kg⁻¹, respectively, showing severe contamination. Among 20 species native to this area, Pteris ensiformis accumulated 1091 mg kg⁻¹ As in the shoot, and its translocation factor (TF) was greater than 1, suggesting potential capacity for As phytoextraction. Boehmeria nivea, Aster prorerus, and Hydrocotyle sibthorpioides showed potential for phytoextraction of Cd due to their high accumulation of Cd in shoots (490.3, 175.4, and 128.5 mg kg⁻¹, respectively) and high TFs (92.0, 22.1, and 6.7, respectively). Eleusine indica and P. ensiformis were found to contain high concentrations of Pb (7474 mg kg⁻¹) and Zn (1662 mg kg⁻¹) in roots, but with low TFs for Pb (0.4) and Zn (0.2), suggesting potential capability for phytostabilization. There was a positive correlation (p < 0.01, N = 25) of TFs between the metal(loid)s, indicating a synergic interaction in the uptake of metal(loid)s by these plants. According to metal(loid) concentrations in shoots, bioconcentration factors (BFs), and TFs, as well as the botanical features such as wide occurrence, high biomass yield, and rapid growth of the plants, the five native species identified above have the potential for phytoremediation in the Baoshan mining area.
Show more [+] Less [-]Meltwater hydrochemistry at four glacial catchments in the headwater of Indus River Full text
2019
Zhang, Fan | Qaiser, Faizan-ur-Rehman | Zeng, Chen | Pant, Ramesh Raj | Wang, Guanxing | Zhang, Hongbo | Chen, Deliang
Glacier runoff shows significant change under global warming in the headwater region of the Indus River with great impact on its highly populated downstream area, but the hydrochemistry characteristics of meltwater and the changing mechanism remain unclear in this region. In this study, runoff water samples were collected during May and June, 2015, from four glacial catchments in the Upper Indus Basin to investigate general characteristics and daytime dynamics of meltwater runoff together with sediment and chemical contents. Results showed that glacier runoff in the studied area had an alkaline pH and much higher sediment yields than the local average of the non-glacier areas. The carbonate-dominated geological feature in the four catchments resulted in single chemical facies of Ca–HCO₃. The dominant process determining the glacier runoff chemistry was rock-water interaction, with less soluble minerals and less intensive evaporate weathering in the Passu and Gulmit catchments than the B&B and Hinarchi catchments. Comparing the investigated catchments, the larger glacier with longer flow path exhibited higher runoff but lower melting rate, higher SSC resulting from higher erosive power of flow, and higher solute concentrations as a consequence of more intensive contact of meltwater with rock minerals along the longer flow path. For individual catchments, a negative correlation between TDS and flow rate (R² = 0.26~0.53) and changing trends of ion ratios with flow rate demonstrated that under intensive melting conditions, rock-water interactions were reduced, resulting in dilution of solutes. Overall, the general chemical characteristics of the investigated glacier runoff indicated geological control, whereas individual glacier illustrated hydrological control on the daytime dynamics of glacier runoff chemistry. The presence of glacier terminal lake and agriculture land can significantly alter the hydrochemistry of downstream runoff.
Show more [+] Less [-]Cadmium phytoextraction from contaminated paddy soil as influenced by EDTA and Si fertilizer Full text
2019
Zhang, Pengbo | Zhao, Dandan | Liu, Yuqiao | Zhang, Yangzhu | Wei, Xiao | Xu, Bo | Bocharnikova, Elena | Matichenkov, Vladimir
The efficiency of heavy metal (HM) phytoextraction from contaminated soil directly depends on the pollutant bioavailability, which can be increased by some soil amendments. In field test, the impacts of soil-applied ethylenediaminetetraacetic acid (EDTA) and amorphous silicon dioxide (ASD) and foliar-applied monosilicic acid (MS) on cadmium (Cd) uptake by rice plants from contaminated paddy soil were investigated. Without EDTA, the solid or liquid Si materials reduced the Cd accumulation in the aboveground part of rice by 26 to 52%. If EDTA was applied, the Cd accumulation by plants was increased by 60 to 92%; however, the biomass was reduced by 16 to 35%. The combined application of Si-rich materials and EDTA provided enhanced plant tolerance to a negative influence of EDTA, while kept high Cd content in the rice stems and leaves. As a result, the Cd amounts extracted by the stems and leaves from the unit area of contaminated paddy soil were greater by 25 and 37% in comparison with those for only EDTA treatment.
Show more [+] Less [-]Comprehensive evaluation of ecological compensation effect in the Xiaohong River Basin, China Full text
2019
Meng, Yu | Liu, Meng | Guan, Xinjian | Liu, Wenkang
Due to the complexity of ecological compensation standards and methods, some problems cannot be expected before compensation, but the evaluation of eco-compensation effect can feedback the implementation effect of eco-compensation policies and provide reference for the improvement of eco-compensation policies. This paper constructed a comprehensive evaluation index system of eco-compensation, which covered social and economic development, pollution discharge and monitoring, and pollution treatment aspects. An eco-compensation comprehensive evaluation model was established, which consisted of the projection pursuit model (PP model) and the chaotic particle swarm optimization algorithm (CPSO algorithm). The Xiaohong River Basin in China was selected as a case study. Before and after the implementation of eco-compensation policy, the compensation effects in the four counties in the basin from 2008 to 2015 were evaluated. The results showed that through the implementation of the basin eco-compensation policies, the comprehensive indicators in the four counties showed an upward trend, which indicated that the eco-compensation of the basin had achieved certain effects. Among them, Xincai was the best, and could provide reference for other counties. The research results can provide new ideas and new methods for the evaluation of eco-compensation effects.
Show more [+] Less [-]Heavy metals and PAHs in an open fishing area of the East China Sea: Multimedia distribution, source diagnosis, and dietary risk assessment Full text
2019
Wang, Qian | Peng, Fei | Chen, Yiqin | Jin, Ling | Lin, Jun | Zhao, Xu | Yin, Jie | Li, Juan-Ying
This study involved a comprehensive investigation of heavy metals and polycyclic aromatic hydrocarbons (PAHs) in seawater, sediments, and seafoods in an important open fishing area connecting China and Japan. Cu, Pb, Cd, Cr, As, and PAHs were detected in all the studied environmental media. Specifically, Pb and low molecular weight PAHs (LMW-PAHs) were observed at high levels, due to intensive ship activities and accidental crude oil spills. Additionally, source diagnosis of PAHs suggested a potential impact from combustion. Bioaccumulation factors (BAFs) and biota-sediment accumulation factors (BSAF) suggested moderate or low bioaccumulation potentials of the analytes from water and sediments, respectively. Noncarcinogenic risk assessment, based on target hazard quotients (THQs), indicated a potential low risk by consuming the studied seafoods, while the incremental lifetime carcinogenic risk assessment (ILCRs) suggested “acceptable risk” or “potential risk.” However, it should be noted that there have been possibilities that the carcinogenic risk could be elevated due to bioaccumulation of the PAHs in the seafoods after long-term exposure. In summary, it is necessary to evaluate the seafood security carefully in this open fishing area due to the potential health risks.
Show more [+] Less [-]Performance evaluation of a decentralized wastewater treatment system in India Full text
2019
Singh, Anju | Sawant, Megha | Kamble, Sheetal Jaisingh | Herlekar, Mihir | Starkl, Markus | Aymerich, Enrique | Kazmi, Absar
A Decentralized Wastewater Treatment System (DEWATS) provides an economically feasible and efficient wastewater treatment solution especially in developing countries. It has an enormous potential for developing a sustainable environmental sanitation system. In this study, the treatment efficiency of eight DEWATS plants was evaluated in the state of Maharashtra, India, for their performance in terms of selected physico-chemical parameters of the wastewater. Although the efficiency of some of the plants was lower than that reported in literature, the effluent quality of all the plants was within the permissible discharge limits of the Central Pollution Control Board for all the parameters. Comprehensive assessment of Plant I was carried in terms of its technical and socio-economic aspects. Moreover, LCA tool has been utilized to evaluate the environmental impacts of the operation stage of DEWATS. The midpoint, CML 2001 (April 2015) methodology was adopted, in which 11 impact categories were considered. From the life cycle impact assessment and interpretation, the main impacts are identified as releases of COD, P-PO₄³⁻, and N-NH₄⁺ to water bodies and disposal of sludge. Due to negligible energy consumption, the operation stage was found to be less damaging to the environment. It was concluded that DEWATS can be a good alternative for treating wastewater with negligible energy and chemical consumption.
Show more [+] Less [-]Attitudes to climate change, perceptions of disaster risk, and mitigation and adaptation behavior in Yunlin County, Taiwan Full text
2019
Lee, Yung-Jaan | Tung, Chuan-Ming | Lin, Shih-Chien
Issues that are associated with climate change have global importance. Most related studies take a national or regional perspective on the impact of climate change. Taiwan is constrained by its geographical conditions, which increase its vulnerability to climate change, especially in its western coastal areas. The county that is most affected by climate change is Yunlin. In 2013–2014, projects that were sponsored by Taiwan’s government analyzed the relationship among synthesized vulnerability, ecological footprint (EF) and adaptation to climate change and proposed 15 categories of synthesized vulnerability and EF values. This study further examines the relationship between vulnerability and EF values and examines how residents of four townships—Linnei, Sihu, Mailiao, and Huwei—cope with the effects of climate change. This study investigates whether the residents of the four townships vary in their attitudes to climate change, their perceptions of disaster risk, and their behavioral intentions with respect to coping with climate change. The structural equation model (SEM) is used to examine the relationships among attitudes to climate change, perceptions of disaster risk, and the behavioral intentions of residents in townships with various vulnerabilities to climate change. The results that are obtained using the SEM reveal that climate change mitigation/adaptation behavior is affected by attitudes to climate change and perceptions of disaster risk. However, the effects of attitudes and perceptions on mitigation and adaptation that are mediated by place attachment are not statistically significant.
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