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A critical review of the development, current hotspots, and future directions of Lake Taihu research from the bibliometrics perspective Full text
2016
Zhang, Yunlin | Yao, Xiaolong | Qin, Boqiang
Lake Taihu, as the important drinking water source of the Yangtze River Delta urban agglomeration and the third largest freshwater lake in China, has experienced serious lake eutrophication and water quality deterioration in the past three decades. Growing scientific, political, and public attention has been given to the water quality of Lake Taihu. This study aimed to conduct a comparative quantitative and qualitative analysis of the development, current hotspots, and future directions of Lake Taihu research using a bibliometric analysis of eight well-studied lakes (Lake Taihu, Lake Baikal, Lake Biwa, Lake Erie, Lake Michigan, Lake Ontario, Lake Superior and Lake Victoria) around the world based on the Science Citation Index (SCI) database. A total of 1582 papers discussing Lake Taihu research were published in 322 journals in the past three decades. However, the first paper about Lake Taihu research was not found in the SCI database until 1989, and there were only zero, one, or two papers each year from 1989 to 1995. There had been rapid development in Lake Taihu research since 1996 and a sharp increase in papers since 2005. A keyword analysis showed that “sediment,” “eutrophication”, “Microcystis aeruginosa”, “cyanobacterial blooms”, and “remote sensing” were the most frequently used keywords of the study subject. Owing to its significant impact on aquatic ecosystems, a crucial emphasis has been placed on climate change recently. In addition, the future focuses of research directions, including (1) environmental effects of physical processes; (2) nutrient cycles and control and ecosystem responses; (3) cyanobacteria bloom monitoring, causes, forecast and management; (4) eutrophication and climate change interactions; and (5) ecosystem degradation mechanism and ecological practice of lake restoration, are presented based on the keyword analysis. Through multidisciplinary fields (physics, chemistry, and biology) cross and synthesis study of Lake Taihu, the development of shallow lake limnology will be largely promoted.
Show more [+] Less [-]Microbial fuel cell assisted nitrate nitrogen removal using cow manure and soil Full text
2016
Vijay, Ankisha | Vaishnava, Monika | Chhabra, Meenu
Microbial fuel cells (MFCs) are emerging wastewater treatment systems with a proven potential for denitrification. In this study, we have developed a high-rate denitrifying MFC. The anode consisted of cow manure and fruit waste and the cathode consisted of cow manure and soil. The initial chemical oxygen demand (COD)/nitrate nitrogen (NO₃ ⁻-N) was varied from 2 to 40 at the cathode while keeping the anode ratio fixed at 100. NO₃ ⁻-N removal rate of 7.1 ± 0.9 kg NO₃ ⁻-N/m³ net cathodic compartment (NCC)/day was achieved at cathode COD/NO₃ ⁻-N ratio 7.31 with the current density of 190 ± 9.1 mA/m² and power density of 31.92 ± 4 mW/m² of electrode surface area. We achieved an open-circuit voltage (OCV) of 410 ± 20 mV at initial cathodic NO₃ ⁻-N of 0.345 g/l. The cathode COD/NO₃ ⁻-N ratio had a significant influence on MFC’s OCV and nitrate removal rate. Lower OCV (<150 mV) and NO₃ ⁻-N removal rates were observed at COD/NO₃ ⁻-N ratio >12 and <7. Experiments done at different cathode pH values indicated that the optimum pH for denitrification was 7. Under optimized biochemical conditions, nitrate removal rate of 6.5 kg NO₃ ⁻-N/m³ net cathodic compartment (NCC)/day and power density of 210 mW/m² were achieved in a low resistance MFC. The present study thus demonstrates the utility of MFCs for the treatment of high nitrate wastes.
Show more [+] Less [-]Salt stress-induced modulations in the shoot proteome of Brassica juncea genotypes Full text
2016
Yousuf, Peerzada Yasir | Ahmad, Altaf | Ganie, Arshid Hussain | Iqbal, Muhammad
Indian mustard [Brassica juncea (L.) Czern and Coss] is cultivated mainly in the northwestern agroclimatic region of India and suffers huge losses in productivity due to salinization. In an effort to figure out adaptation strategies of Indian mustard to salt stress, we conducted a comparative proteome analysis of shoots of its two genotypes, with contrasting sensitivity to salt stress. Differential expression of 21 proteins was observed during the two-dimensional electrophoresis (2DE). The identified salt-stress-responsive proteins were associated with different functional processes including osmoregulation, photosynthesis, carbohydrate metabolism, ion homeostasis, protein synthesis and stabilization, energy metabolism, and antioxidant defense system. Salt-tolerant genotype (CS-52) showed a relatively higher expression of proteins involved in turgor regulation, stabilization of photosystems and proteins, and salt compartmentalization, as compared to salt-sensitive genotype (Pusa Varuna). Our results suggest that modulating the expression of salt-responsive proteins can pave the way for developing salt tolerance in the Indian mustard plants.
Show more [+] Less [-]Degradation of dibutyl phthalate (DBP) by UV-254 nm/H2O2 photochemical oxidation: kinetics and influence of various process parameters Full text
2016
Wang, Dong | Duan, Xiaodi | He, Xuexiang | Dionysiou, Dionysios D.
Degradation of dibuytl phthalate (DBP), a plasticizer and also a widely distributed endocrine disruptor, by UV-254 nm/H₂O₂ advanced oxidation process (AOP) was investigated in this study. A significant DBP removal of 77.1 % at an initial concentration of 1.0 μM was achieved at UV fluence of 160 mJ/cm², initial H₂O₂ dosage of 1.0 mM, and pH of 7.6 ± 0.1. The DBP degradation exhibited a pseudo-first-order reaction kinetic pattern, with the rate constants linearly increasing with increasing H₂O₂ dosage while decreasing with increasing initial DBP concentration and pH value in a specific range. DBP destruction was significantly inhibited in the presence of alkalinity and natural organic matter (NOM), two known factors that should be taken a serious consideration of in the research and design of UV/H₂O₂-based AOPs. Presence of common inorganic anions (i.e., Cl⁻, SO₄ ²⁻, and NO₃ ⁻) and metal cations (i.e., Fe³⁺ and Zn²⁺) had a slight impact on the degradation of DBP, although Cu²⁺ could improve the degradation efficiency even at a concentration as low as 0.01 mg/L, suggesting a strong potential of applying UV/H₂O₂ for the removal of DBP with an environmental relevant level of copper.
Show more [+] Less [-]Elemental sulfur in sediments: analytical problems Full text
2016
Rogowska, Justyna | Sychowska, Joanna | Cieszynska-Semenowicz, Monika | Wolska, Lidia
In the paper, a modified method for elemental sulfur (S₈) determining using gas chromatography coupled with mass spectrometry (GC-MS) is proposed with estimation of selected validation parameters. The aim of this work was a review of problems associated with the determination of S₈ and selection of the most optimal conditions for S₈ analysis with GC-MS. The presented studies have shown that the temperature of the injector and the chromatographic column during S₈ determination should not exceed 180 °C. At temperatures over 180 °C, the sulfur S₈ is decomposed to the other sulfur species such as S₂, S₃, S₄, S₅, and S₆. During decreasing injector and column temperature below 180 °C the chromatographic peak eluted as S₈ is badly extended and asymmetric. To minimize the problems of S₈ decomposition to other sulfur species during chromatographic process also other parameters of the GC-MS have been selected. In order to apply the proposed method for real sediments samples, determination of sulfur S₈ in bottom sediments, collected in the Gulf of Gdansk (southern Baltic Sea), has been performed. The concentration of S₈ fell in the range from below the limit of detection to 0.1432 ± 0.0095 mg/g d.w. The research has also shown that addition of approx. 200 mg of activated copper is effective for removing sulfur from bottom sediment extracts.
Show more [+] Less [-]Risk assessment and vertical distribution of thallium in paddy soils and uptake in rice plants irrigated with acid mine drainage Full text
2016
Huang, Xuexia | Li, Ning | Wu, Qihang | Long, Jianyou | Luo, Dinggui | Zhang, Ping | Yao, Yan | Huang, Xiaowu | Li, Dongmei | Lu, Yayin | Liang, Jianfeng
The objective of this paper is to assess the influence of irritating paddy fields with acid mine drainage containing thallium (Tl) to rice plant-soil system and potential health risks for local residents. Vertical distribution of Tl, pH, organic matter (OM), and cation exchange capacity (CEC) in 24 paddy soil profiles around Yunfu pyrite mine area was investigated. Rice plant samples were collected from the corresponding soil sampling site. The results showed that Tl concentrations in paddy soils at 0–60 cm depth range from 3.07 to 9.42 mg kg⁻¹, with a mean of 5.74 mg kg⁻¹, which were significantly higher than the background value of soil in China (0.58 mg kg⁻¹). On the whole, Tl contents in paddy soil profiles increased quickly with soil depth from 0 to 30 cm and decreased slowly with soil depth from 30 to 60 cm. The soil Tl content was significant negatively correlated with soil pH. The mean content of Tl in the root, stem, leaf, and rice was 4.36, 1.83, 2.74, and 1.42 mg kg⁻¹, respectively, which exceeded the proposed permissible limits for foods and feedstuffs in Germany. The Tl content in various tissues of the rice plants followed the order root > leaf > stem (rice), which suggested that most Tl taken up by rice plants retained in the root, and a little migrated to the leaf, stem, and rice. Correlation analysis showed that Tl content in root was significant positively correlated with Tl content in leaf and rice. The ranges of hazard quotient (HQ) values were 4.08∼24.50 and 3.84∼22.38 for males and females, respectively. Males have higher health risk than females in the same age group. In childhood age groups (2 to <21 years) and adult age groups (21 to <70 years), the highest health risk level was observed in the 11 to 16 age group and 21 to 50 age group, respectively. The findings indicated that regular irrigation with Tl-bearing acid mine drainage led to considerable contamination of Tl in paddy soil and rice plant. Local government should take various measures to treat Tl contamination, especially the tailings.
Show more [+] Less [-]A system coupling hybrid biological method with UV/O3 oxidation and membrane separation for treatment and reuse of industrial laundry wastewater Full text
2016
Mozia, Sylwia | Janus, Magdalena | Brożek, Piotr | Bering, Sławomira | Tarnowski, Krzysztof | Mazur, Jacek | Morawski, Antoni W.
The possibilities of application of a three-step system combining hybrid biological treatment followed by advanced UV/O₃ oxidation with in situ generated O₃ and membrane separation (ultrafiltration (UF) and nanofiltration (NF)) to treat and reuse the wastewater from an industrial laundry are presented. By the application of a hybrid moving bed biofilm reactor (HMBBR), the total organic carbon concentration was reduced for about 90 %. However, since the HMBBR effluent still contained organic contaminants as well as high concentrations of inorganic ions and exhibited significant turbidity (8.2 NTU), its further treatment before a possible reuse in the laundry was necessary. The UV/O₃ pretreatment prior to UF was found to be an efficient method of the membrane fouling alleviation. During UF, the turbidity of wastewater was reduced below 0.3 NTU. To remove the inorganic salts, the UF permeate was further treated during NF. The NF permeate exhibited very low conductivity (27–75 μS/cm) and contained only small amounts of Ca²⁺ and Mg²⁺; thus ,it could be reused at any stage of the laundry process.
Show more [+] Less [-]Occurrence of pharmaceuticals and UV filters in swimming pools and spas Full text
2016
Ekowati, Yuli | Buttiglieri, Gianluigi | Ferrero, Giuliana | Valle-Sistac, Jennifer | Díaz-Cruz, M. Silvia | Barceló, Damià | Petrović, M. (Mira) | Villagrasa, Marta | Kennedy, Maria D. | Rodríguez-Roda, Ignasi
The occurrence of 32 pharmaceuticals and 14 UV filters in swimming pools and spas was studied. Fifty-one water samples were collected from 17 pools located in sport centres and hotels in Catalonia, Spain. The samples were analysed by liquid chromatography-tandem mass spectrometry. The pharmaceuticals atenolol, carbamazepine, hydrochlorothiazide, metronidazole, ofloxacin, sulfamethoxazole, acetaminophen, ibuprofen, ketoprofen and phenazone were measured in water samples at concentrations higher than their limit of quantification (LOQ). The highest concentration of any individual pharmaceutical was measured for the diuretic hydrochlorothiazide (904 ng/L). The most frequently detected pharmaceutical was carbamazepine, as it was observed in more than half of all the water samples measured (53 %, 27/51). The UV filters at concentrations higher than LOQ in water samples were BP1, BP2, BP3, BP8, THB, 4DHB, 4MBC, OD-PABA, 1HBT, MeBT and DMeBT. The highest concentration of UV filter observed was 4MBC (69.3 ng/L) while the most frequent UV filters in the samples were 1HBT (59 %, 30/51). The results also showed that pharmaceuticals and UV filters were most frequently found in spas. Finally, from a water treatment technology perspective, the lowest occurrence of pharmaceuticals was in the pools applying sand filters followed by disinfection by sodium hypochlorite, while the lowest occurrence of UV filters was in the pools applying coagulation, sand filtration, UV and salt electrolysis.
Show more [+] Less [-]Additional disturbances as a beneficial tool for restoration of post-mining sites: a multi-taxa approach Full text
2016
Řehounková, Klára | Čížek, Lukáš | Řehounek, Jiří | Šebelíková, Lenka | Tropek, Robert | Lencová, Kamila | Bogusch, Petr | Marhoul, Pavel | Máca, Jan
Open interior sands represent a highly threatened habitat in Europe. In recent times, their associated organisms have often found secondary refuges outside their natural habitats, mainly in sand pits. We investigated the effects of different restoration approaches, i.e. spontaneous succession without additional disturbances, spontaneous succession with additional disturbances caused by recreational activities, and forestry reclamation, on the diversity and conservation values of spiders, beetles, flies, bees and wasps, orthopterans and vascular plants in a large sand pit in the Czech Republic, Central Europe. Out of 406 species recorded in total, 112 were classified as open sand specialists and 71 as threatened. The sites restored through spontaneous succession with additional disturbances hosted the largest proportion of open sand specialists and threatened species. The forestry reclamations, in contrast, hosted few such species. The sites with spontaneous succession without disturbances represent a transition between these two approaches. While restoration through spontaneous succession favours biodiversity in contrast to forestry reclamation, additional disturbances are necessary to maintain early successional habitats essential for threatened species and open sand specialists. Therefore, recreational activities seem to be an economically efficient restoration tool that will also benefit biodiversity in sand pits.
Show more [+] Less [-]Effects of γ-Fe2O3 nanoparticles on the survival and reproduction of Biomphalaria glabrata (Say, 1818) and their elimination from this benthic aquatic snail Full text
2016
Oliveira-Filho, Eduardo C. | Filho, José Sousa | Novais, Luana A. | Peternele, Wilson S. | Azevedo, Ricardo B. | Grisolia, Cesar K.
This study aims to evaluate the effects of maghemite nanoparticles (γ-Fe₂O₃) coated with meso-2, 3-dimercaptosuccinic acid (DMSA) stabilizer on the survival and reproduction of the aquatic snail Biomphalaria glabrata. The cumulative means of egg masses and eggs per individual in the control group at the end of 4 weeks were 18.8 and 326.7, respectively. These values at the concentration of 1 mg/L were 17.2 and 291.6; at 10 mg/L, they were 19.6 and 334.4 ,and at 100 mg/L, they were 14.3 and 311.1. Results showed no significant differences between the tested and the control groups at the level of p < 0.05. Exposure of embryos for 10 days showed absence of mortality, malformation, or hatching delay. X-ray microtomography confirmed the presence of nanoparticles in exposed individuals and showed the complete elimination of the nanoparticles after 30 days in clean water. In the studied conditions, it is clear that γ-Fe₂O₃ coated with stabilizing DMSA did not alter the fecundity or the fertility of the snail B. glabrata after 4 weeks of exposure, and accumulation was not present after 30 days in clean water.
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