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Chemical characterization of mountain forest soils: impact of long-term atmospheric deposition loadings (Czech–Polish–German border region) Full text
2020
Havelcová, Martina | Machovič, Vladimír | Novák, František | Lapčák, Ladislav | Mizera, Jiří | Hendrych, Jiří
The composition of lipids in soil offers clues to soil degradation processes due their persistency and selectivity in soil, and close relation to long-term processes in the ecosystem, thanks to their role in cell membranes of organisms. Organic solvent-extractable compounds were recovered from soils collected at two sites differing in the degree of forest damage. Gas chromatography/mass spectroscopy and Fourier transform infrared spectroscopy were applied in order to characterize solvent-extractable lipids. Raman spectroscopy was also applied as it provides distinct advantages for determining the structural order of carbonaceous materials. The organic matter measurement techniques were combined with an established simultaneous multi-element measurement technique. Variations in individual soil horizons from the sites were reflected in the crystallinity of epicuticular waxes, presence of long-chain aliphatic hydrocarbons, concentrations of n-alkanes, saturated and unsaturated fatty acids, dicarboxylic acids, and in the content of aromatic structures, hydroxyl, ester, and carboxylic acid groups. The results are explained by differently transformed organic matter. The concentrations of elements in the soils were also affected by atmospheric depositions, including higher accumulations of arsenic and antimony, and lower contents of natural nutrients. These data have potential to be used as sensitive biogenic indicators of ecosystem damage by long-term atmospheric depositions.
Show more [+] Less [-]Investigation of the vulnerability of a partly covered karst feature in Veszprém, Hungary Full text
2020
Trájer, Attila J. | Mlinárik, Lilla | Hammer, Tamás | Földényi, Rita | Somlai, János | Bede-Fazekas, Ákos
Karst aquifers represent the most important renewable sources of drinking water. Because anthropogenic influences threaten the integrity of karst aquifers, it is important to determine the soil erosion and karst denudation rates. In order to study the complex signs of degradation processes of the karst, a paleodoline (paleo-polje) was selected near to the county seat Veszprém, Hungary. It was found that gamma radiation measurements can be a useful tool to detect the level of soil erosion since the low gamma radiation indicates the surface proximity of the carbonate bedrock. The level of gamma radiation also predicts the potential agricultural usability of a site. Both the patterns of contamination and the erosion attack zone are strongly defined by the relief. The gullies and the deepest parts of the karstic landscape are the traps of organic materials and pollutants. The amounts of ⁴⁰K and its decay products originate from the covering sediment and negatively correlate with the soil depth. In the case of covered karsts, the measuring of the concentration of radionuclides and field gamma-ray dose measurement together can characterize the general horizontal and vertical trends of soil erosion, the potential land use, and the vegetation.
Show more [+] Less [-]Impact assessment of Bt maize expressing the Cry1Ab and Cry2Ab protein simultaneously on non-target arthropods Full text
2020
Yin, Yue | Xu, Yudi | Cao, Kaili | Qin, Zifang | Zhao, Xinxin | Dong, Xuehui | Shi, Wangpeng
Transgenic maize expressing the Cry1Ab and Cry2Ab protein simultaneously from Bacillus thuringiensis (Bt-maize) has been grown for farm-scale study to investigate its potential impact to non-target arthropod (NTA). The trials were conducted between Bt maize 2A-7 and its parental line (B73-329) in Beijing, China, over 3 years. Richness (C), Shannon index (H), Pielou index (J), Simpson index (D), and Bray-Curtis index were used to evaluate the population dynamics and biodiversity of the dominant arthropods from per 50 plants in crop field. The mainly abundant groups were Aphidoidea, Araneae, Coccinellidae, Anthocoridae, and Thripidae which represented about 90% of the total number of NTA. Although the abundance of NTA varied from year to year, there is no significant difference between Bt maize and non-Bt maize field. Fluctuations were found at individual sample dates, but the trend of these descriptors remained consistent. Further analysis showed the biodiversity indexes of the dominant arthropods C, H, J, D, and Bray-Curtis dissimilarity between Bt maize producing Cry1Ab and Cry2Ab toxin simultaneously and its parental line had no significant difference except for some sampling dates. These results suggested that Bt maize is compatible with the NTAs and provides further evidence of the ecological impact of genetically modified maize.
Show more [+] Less [-]Ca, Cu, and Li in washed and unwashed specimens of needles, bark, and branches of the blue spruce (Picea pungens) in the city of Ankara Full text
2020
Cetin, Mehmet | Sevik, Hakan | Cobanoglu, Oguzhan
The use of certain types of plants to determine the accumulation of HMs (heavy metals) has yielded quite consistent results in the research fields. Many researches have focused on particular types of HMs due to their common presence in the air (Pb, Cd, Ni, Co, Cr to name a few). However, it is equally as important to shed light on other types of HMs and the scale of their existence in our atmosphere, hence this paper. Blue spruce (Picea pungens) tree organs were used in an experiment to calculate the recent concentration of HMs. The research concentrates on Ca, Cu, and Li elements in the washed and unwashed needles, branches, and barks, and these organs were evaluated depending on the organ age. The study results showed that the concentration of the elements subjected to the research changed depending on the organ, washing status and organ age, and that the lowest concentrations of Ca and Cu elements were obtained in the barks in general. In relation to the organ age, it was found that there was an increase in the concentration of Ca with age, and that the concentration of Li element was inversely proportional to age.
Show more [+] Less [-]Assessment of spring water quality and associated health risks in a high-level natural radiation area, North Iran Full text
2020
Amini Birami, Farideh | Moore, Farid | Faghihi, Reza | Keshavarzi, Behnam
In this study, the spring water quality of a high natural background radiation region in North Iran was evaluated by measuring hydrochemical characteristics and concentration of potentially toxic elements (PTEs) and activity concentration of radioactive elements. The carcinogenicity potential from exposure to PTEs and radioactive elements was also investigated using probabilistic approach. The hydrochemical properties of water samples revealed that there were two different water types in the study area: (1) non-thermal Ca-HCO3 type and (2) thermal Na-Cl type. The concentrations of Al, Cd, Cr, Cu, Pb, Mo, Ni, Sb, Zn, and ⁴⁰K were within the recommended water quality standard set by the World Health Organization (WHO). Elevated concentrations of As, Mn, Hg, ²²⁶Ra, and ²³²Th occur in Na-Cl water type while elevated concentrations of Fe occur in Ca-HCO₃ water type. Also, health complications of dermal contact (via balneology or bathing) are within the safe limits. The major concern regarding the contaminated springs is the possibility of soil and groundwater contamination through uncontrolled runoff and spa effluents. Preventing the spread of toxic constituents in the study area via high-risk spring water requires periodic monitoring, and applying control measures where necessary.
Show more [+] Less [-]Correction to: Associations of trace elements in blood with the risk of isolated ventricular septum defects and abnormal cardiac structure in children Full text
2020
Zhu, Yu | Xu, Cheng | Zhang, Yuxi | Xie, Zongyun | Shu, Yaqin | Lu, Changgui | Mo, Xuming
The original publication of this paper contains an error.
Show more [+] Less [-]Green preparation of activated carbon from pomegranate peel coated with zero-valent iron nanoparticles (nZVI) and isotherm and kinetic studies of amoxicillin removal in water Full text
2020
Ali, Imran | Afshinb, Shirin | Poureshgh, Yousef | Āz̲arī, ʻAlī | Rashtbari, Yousef | Feizizadeh, Abolfazl | Hamzezadeh, Asghar | Fazlzadeh, Mehdi
In present research, the activated carbon was prepared by a green approach from pomegranate peel coated with zero-valent iron nanoparticles (AC-nZVI) and developed as adsorbent for the removal of amoxicillin from aqueous solution. The physicochemical properties of the AC-nZVI were investigated using XRD, FTIR, and FESEM techniques. The optimal values of the parameters for the best efficiency (97.9%) were amoxicillin concentration of 10 mg/L, adsorbent dose of 1.5 g/L, time of 30 min, and pH of 5, respectively. The adsorption equilibrium and kinetic data were fitted with the Langmuir monolayer isotherm model (qmax 40.282 mg/g, R² 0. 0.999) and pseudo-first order kinetics (R² 0.961). The reusability of the adsorbent also revealed that the adsorption efficiency decreased from 83.54 to 50.79% after five consecutive repetitions. Overall, taking into account the excellent efficiency, availability, environmental friendliness, and good regeneration, AC-nZVI can be introduced as a promising absorbent for amoxicillin from aquatic environments.
Show more [+] Less [-]Assessing barriers and solutions for Yemen energy crisis to adopt green and sustainable practices: a fuzzy multi-criteria analysis Full text
2020
Al Asbahi, Ahmed Abdulwali Mohammed Haidar | Fang, ZhiGeng | Chandio, Zaheer Ahmed | Tunio, Mehran Khan | Ahmed, Javed | Abbas, Majed
Currently, the renewable energy sectors have dynamically revolved around targeting green turbulence, mainly due to increased customer environmental awareness. Therefore, this paper investigates green initiatives. The results show barriers and explain the strategies for adopting green renewable energy sources in Yemen. The political barrier has the highest weight of 0.191, while technical barrier sored the second highest weight of 0.181. The weights of managerial and information energy were found to be 0.18 and 0.17, respectively. Market barrier weighed the lowest score of 0.12, while economic barrier (0.15 weight) is the barrier to develop renewable energy road map. The research developed a comprehensive decision making framework to identify major barriers, sub-barriers, and develop plans for green energy in Yemen. Fuzzy analytical hierarchal process (FAHP) results indicate that the category of political obstacles is more important than other obstacles. Yemen has undergone power reforms and achieved better energy efficiency, compared to the countries that have applied imperfect. Economic efficiency in Yemen is the lowest among the considered barriers. Twenty-five percent of the considered barriers were identified with an alarming efficiency of 0.5%. The effects of FTOPSIS show that the planned explanation “developing research methods to achieve green innovation in renewable” energy is significant to address the obstacles to green innovation in renewable energy.
Show more [+] Less [-]Comprehensive evaluation on water resource carrying capacity in karst areas using cloud model with combination weighting method: a case study of Guiyang, southwest China Full text
2020
Peng, Tao | Deng, Hongwei
It is important to maintain the sustainable development of water resources. Objective assessment on water resource carrying capacity (WRCC) is beneficial to the formulation of scientific and reasonable water management practices. In view of the problem that evaluation indicators of WRCC cannot describe the fuzziness and randomness, a cloud model was introduced into regional WRCC assessment. This study selected a typical karst area (Guiyang) as the research object to study WRCC by using cloud model with combination weighting method. WRCC was assessed from the following five dimensions: water environment subsystem, social subsystem, economic subsystem, ecological subsystem, and humanities (water resource management and policy regulation) subsystem. In addition, evaluation results after normalizing all of indicators data were also calculated. And these two kinds of evaluation results were compared with that of technique of order preference similarity to the ideal solution (TOPSIS), finding that evaluation results of cloud model were consistent with that of TOPSIS method. The cloud model realizes the transformation from qualitative evaluation to quantitative evaluation, which overcome insufficiencies of traditional evaluation methods in considering fuzziness and randomness. Results showed that during the period of 2008–2017, the state of WRCC in Guiyang was improving year by year, increasing from the serious overload carrying capacity level in 2008 to the strong carrying capacity level in 2017 (serious overload-overload-critical-weak carrying capacity–strong carrying capacity). However, some certain evaluation indicators are still in danger situation, such as population natural growth rate and use of the fertilizer per unit cultivated area, which needs to be further enhanced and improved. Moreover, the contradiction among economic development, population growth, and water resources is becoming increasingly apparent. To ensure the effective utilization of water resources in Guiyang, reasonable policies and measures should be formulated and put into effect. Research results could provide certain reference for the sustainable development of regional water resources.
Show more [+] Less [-]A non-conformational QSAR study for plant-derived larvicides against Zika Aedes aegypti L. vector Full text
2020
Saavedra, Laura M. | Romanelli, Gustavo P. | Duchowicz, Pablo R.
A set of 263 plant-derived compounds with larvicidal activity against Aedes aegypti L. (Diptera: Culicidae) vector is collected from the literature, and is studied by means of a non-conformational quantitative structure-activity relationships (QSAR) approach. The balanced subsets method (BSM) is employed to split the complete dataset into training, validation and test sets. From 26,775 freely available molecular descriptors, the most relevant structural features of compounds affecting the bioactivity are taken. The molecular descriptors are calculated through four different freewares, such as PaDEL, Mold², EPI Suite and QuBiLs-MAS. The replacement method (RM) variable subset selection technique leads to the best linear regression models. A successful QSAR equation involves 7-conformation-independent molecular descriptors, fulfiling the evaluated internal (loo, l30%o, VIF and Y-randomization) and external (test set with Nₜₑₛₜ = 65 compounds) validation criteria. The practical application of this QSAR model reveals promising predicted values for some natural compounds with unknown experimental larvicidal activity. Therefore, the present model constitutes the first one based on a large molecular set, being a useful computational tool for identifying and guiding the synthesis of new active molecules inspired by natural products.
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