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Using the method of dynamic factors for assessing the transfer of chemical elements from soil to plants from various perspectives 全文
2019
Baltrėnaitė, Edita | Baltrėnas, Pranas
Environmental, biological, and ecosystem-specific properties may influence the transfer of chemical elements (CEs) from soils to plants, including the variation in the chemical elements’ concentration, their types, and physiological parameters, such as biotransformation ability in the plants. The interface between the soil and a plant, or the concentration of a particular chemical element in a plant with respect to its concentration in the soil, is the basis for a widely used biological absorption coefficient, also known as the transfer factor, bioaccumulation factor, mobility ratio, or plant-soil coefficient, which is expressed in terms of the chemical element’s concentration in the plant and soil. However, from the biogeochemical perspective, these coefficients/factors can provide a comparison of the chemical element (CE) concentration in different media (plants and soil), but only in a particular place (under typical environmental conditions) and at a particular time. However, factors that highlight the variation in the processes, rather than the variation in the chemical element quantity under the conditions of the environmental variation, are required. The second-level or dynamic factors can be used for this purpose. A quantitative method, using the dynamic factors of bioaccumulation, biophilicity, translocation, bioavailability, and phytoremediation, is offered to assess the variation in the process of the uptake of chemical elements by different plants, to evaluate the influence of soil modification on their participation in the plants’ metabolism and to perform quantitative evaluation of phytoremediation efficiency over a particular period of time. The use of dynamic factors for describing the chemical elements’ uptake by plants in various cases, representing aerogenic and edaphic chemical elements’ transfer, is discussed.
显示更多 [+] 显示较少 [-]Freshwater lake ecosystem health assessment and its response to pollution stresses based on planktonic index of biotic integrity 全文
2019
Zhang, Huayong | Duan, Zhengda | Wang, Zhongyu | Zhong, Meifang | Tian, Wang | Wang, Hualin | Huang, Hai
Based on the planktonic data monitored in Lake Balihe, an ecosystem health assessment system referring to planktonic index of biotic integrity (P-IBI) was constructed to evaluate the lake health status and study the response mechanism of P-IBI to environmental factors. The results showed that a total of 7 phylum 59 species of phytoplankton and 3 phylum 28 species of zooplankton were identified in the lake, and both the plankton density and biomass varied significantly in time and space scales. The significant variation of Protozoa density should be responsible to the inconsistency between the distributions of zooplankton density and biomass, as well as the lowest value of P-IBI in summer. The P-IBI values and therefore the health levels can be seasonally ranked as winter > autumn > spring > summer and found spatially increased along the flow direction. Based on the relationships between P-IBI and the environmental factors, ammonia nitrogen = 0.46 mg/L and Secchi depth = 63 cm were found as the environmental protection thresholds of planktonic biotic integrity for this freshwater lake ecosystem. The findings of the research may provide some guidance to the ecological monitoring and protection of freshwater lake.
显示更多 [+] 显示较少 [-]A holistic study of neonicotinoids neuroactive insecticides—properties, applications, occurrence, and analysis 全文
2019
Buszewski, Boguslaw | Bukowska, Małgorzata | Ligor, Magdalena | Staneczko-Baranowska, Irena
Among pesticides and foliar sprays involved in the treatment of seed, soil, and grass, also to crops, an important group is neonicotinoids. Neonicotinoid pesticides present similar properties with nicotine, but the mentioned compounds are less harmful for humans. Nevertheless, neonicotinoids are poisonous to insects and some invertebrates, which can act against insects’ central nervous system, leading to their death. Moreover, neonicotinoids can affect the reproduction, foraging, and flying ability of honeybee and other insects including pollinators. In the present study, some neonicotinoids, such as imidacloprid, acetamiprid, clothianidin, thiacloprid, and thiamethoxam together with their toxic effects, have been presented. The Environmental Protection Agency (EPA) classifies these neonicotinoids as II and III class toxicity agents. Due to accumulation of these pesticides into the pollen of treated plants, especially due to their toxic effects against pollinators, the consequences of the occurrence of these insecticides have been discussed. Analytical aspects and methods involved in the isolation and determination of this class of pesticides have been presented in this contribution.
显示更多 [+] 显示较少 [-]A global prospective of environmental degradations: economy and finance 全文
2019
Hafeez, Muhammad | Yuan, Chunhui | Yuan, Qiuyan | Zhuo, Zhang | Stromaier, David | Sultan Musaad O, Almalki
Finance plays a crucial role in a fast-growing economy that can lead to environmental degradation. The present study utilizes balanced panel data of 105 countries for the time span 1980–2016 to investigate empirical linkage among environmental degradations: economy and finance. It also unfolds the nonlinear impact of economy and finance on environmental degradation. Existing literature on environmental issues mainly focuses on individual case studies uncovering particular regions, but the comprehensive analysis is not available. To fill this gap, panels were classified into five divisions: global, regional, income-based, OECD-based, and carbon emission. The cross-sectional dependence test is applied to identify the degree of cross-sectional dependence among concerned 16 divisions. The second-generation panel models (CADF and Westerlund cointegration, DOLS, and DH heterogenous causality) are employed on a sample set to compute to unit root, cointegration, and long-run and short-run dynamics among concerned variables, respectively. The findings infer the inverted EKC and U-shaped EKC in 10 and 3 out of 16 divisions with respect to environmental degradation—economy nexus, respectively, while 8 and 2 out of 16 divisions indicate the inverted EKC and U-shaped EKC, respectively, in terms of environmental degradation—finance nexus. In 12 out of 16 divisions, the energy consumption uplifts the CO₂ emissions. The DH causality affirmed a bidirectional causality among economy, finance, and energy consumption, respectively.
显示更多 [+] 显示较少 [-]Preparation and optimization photocatalytic activity of polymer-grafted Ag@AgO core-shell quantum dots 全文
2019
Mohammadi, Marziyeh | Hekmatara, Seyedeh Hoda | Moghaddam, Razieh Shekari | Darehkordi, Ali
A linear-dendric copolymer containing polyethylene glycol-polycitric acid used as a capping agent to the green inter-matrix synthesis of silver/silver oxide core-shell quantum dots (Ag@AgO QDs). Water-soluble Ag@AgO QDs were synthesized with high yield and narrow size distribution. Here, Ag ions were trapped in the polymer branches and covalently bonded to it. Another sample of Ag@AgO QDs was synthesized through the same method and conditions without any capping agent (raw nanoparticles). Structure, size distribution, and morphology of raw and copolymer-grafted nanoparticles were identified using X-Ray diffraction, field emission scanning electron microscopy (FESEM), and high-resolution transmission electron microscopy (HRTEM). The results from XRD pattern and UV spectra confirmed the Ag@AgO structure of both nanoparticles. From the FESEM image, the size of Ag nanoparticles obtained at the range of 1–20 nm. HRTEM image of grafted nanoparticles directly showed that these nanoparticles have very tiny size in the range of 1–2 nm and presented in the form of core-shell Ag@AgO. Thus, both raw and polymer-grafted samples are in the range of quantum dots (QDs). Raw and polymer-grafted Ag@AgO QDs which take the advantage of water solubility and biosafety, were used as photocatalyst for degradation of cationic methylene blue (MB) and anionic methyl orange (MO) dyes at low and high concentrations of each dye. Results shows using polymer-grafted QDs leads to a significant enhancement both in the efficiency and rate of dye degradation, compared to the case of using raw nanoparticles.
显示更多 [+] 显示较少 [-]Alpha lipoic acid attenuates the long-term effects of lead exposure in retinal ischemic injury mouse model 全文
2019
Modgil, Shweta | Bammidi, Sridhar | Banik, Avijit | Sharma, Vijay Lakshmi | Anand, Akshay
Lead (Pb) exposure is reported to be unsafe for humans. There have been several studies documenting acute and chronic Pb toxicity on the organ systems. New studies suggest that early-life exposure to such environmental toxins may increase the susceptibility to late-onset degenerative disorders. We aimed to examine the long-term effects of early-life postnatal exposure of Pb on retinal degeneration. Pb exposure (200 ppm) was provided either at postnatal day 1 through lactation (early-life exposure) or at 7th week of age (adulthood exposure) directly through drinking water for 20 days. The Pb-treated mice were followed till 20 weeks of age. At 20th week, ischemia/reperfusion (I/R) injury was induced in these mice by pterygopalatine artery ligation. Further, alpha lipoic acid (ALA) was administered to examine its neuroprotective effects against retinal damage. Histological and molecular analysis revealed that Pb-treated mice had greater retinal damage after I/R injury as compared to untreated or ALA treated mice, suggesting that ALA protects the early-life Pb exposure and its consequent impact on later life. The elevated levels of glial derived neurotrophic factor (GDNF) and ciliary neurotrophic factor (CNTF) and reduced levels of glial fibrillary acidic protein (GFAP) upon ALA pre-treatment suggest that it probably exerts anti-inflammatory effects via upregulation of neurotrophic factors.
显示更多 [+] 显示较少 [-]Assessment of the content, occurrence, and leachability of arsenic, lead, and thallium in wastes from coal cleaning processes 全文
2019
Makowska, Dorota | Strugała, Andrzej | Wierońska, Faustyna | Bacior, Martyna
The aim of the study was to evaluate the content, occurrence, and leachability of arsenic (As), lead (Pb), and thallium (Tl) in wastes from coal cleaning processes with respect to the safe management of this waste. The study focused on wastes resulting from the wet gravitation and flotation processes employed for the purposes of coking coal cleaning in four coal mines situated in the Upper Silesian Coal Basin (Poland). The scope of the study included (i) determination of the content of these elements in the investigated wastes using atomic absorption spectrometry, (ii) evaluation of their mode of occurrence using electron microprobe analysis, and (iii) preliminary assessment of their leachability in deionized water. The content of the analyzed elements in the examined samples of coal waste was twice as high as the average content of these elements in the Earth’s crust. The contents of As and Pb, however, did not exceed their permissible contents in inert waste in accordance with Polish legal regulations based on EU directives. The limit on the content of Tl is not specified by these regulations, but its amount in the examined samples was similar to that occurring in the soils. Moreover, leaching tests have shown that these elements are hardly eluted from the analyzed material. Their content in the water leachates was generally lower than the detection limit of the analytical method, complying with the standards for good and very good water quality. Low leachability of these elements most probably results from their mode of occurrence in the investigated wastes. The chemical analysis using an electron microprobe and the analysis of the correlation between these elements, e.g., total and pyritic sulfur, have shown that Pb, As, and Tl are mainly found in sulfide minerals which are characterized by negligible solubility. In conclusion, the investigated hard coal processing waste does not constitute a threat to the environment and can be commercially used or safely neutralized, e.g., by landfilling.
显示更多 [+] 显示较少 [-]HSPF-based watershed-scale water quality modeling and uncertainty analysis 全文
2019
Roostaee, Maryam | Deng Zhiqiang,
This paper presents findings on uncertainties, introduced through digital elevation model (DEM) resolution and DEM resampling, in watershed-scale flow and water quality (NO₃, P, and total suspended sediment) simulations. The simulations were performed using the Better Assessment Science Integrating Point and Nonpoint Sources/Hydrological Simulation Program Fortran watershed modeling system for two representative study watersheds delineated with both the original DEMs of four different resolutions (including 3.5, 10, 30, and 100 m) and the resampled DEMs of three different resolutions (including 10, 30, and 100 m), creating 14 simulation scenarios. Parameter uncertainties were quantified by means of the GLUE approach and compared to input data uncertainties. Results from the 14 simulation scenarios showed that there was a common increasing trend in errors of simulated flow and water quality parameters when the DEM resolution became coarser. The errors involved in the watershed with a mild slope were found to be substantially (up to 10 times) greater than those of the other watershed with a relatively steep slope. It was also found that sediment was the most sensitive and NO₃ was the least sensitive parameters to the variation in DEM resolution, as evidenced by the maximum normalized root mean square error (NRMSE) of 250% in the simulated sediment concentration and 11% in the simulated NO₃ concentration, respectively. Moreover, results achieved from the resampled (particularly coarser) DEMs were significantly different from corresponding ones from original DEMs. By comparing uncertainties from different sources, it was found that the parameter-induced uncertainties were higher than the resolution-induced uncertainties particularly in simulated NO₃ and P concentrations for studied watersheds. The findings provide new insights into the sensitivity and uncertainty of water quality parameters and their simulation results, serving as the guidelines for developing and implementing water quality management and watershed restoration plans.
显示更多 [+] 显示较少 [-]Bacterial community structure in rotating biological contactor treating coke wastewater in relation to medium composition 全文
2019
Ziembińska-Buczyńska, Aleksandra | Ciesielski, Sławomir | Żabczyński, Sebastian | Cema, Grzegorz
Biological wastewater treatment using biofilm systems is an effective way to treat difficult wastewater, such as coke wastewater. The information about the structure and the dynamics of this microbial community in biofilm, which are responsible for wastewater treatment, is relevant in the context of treatment efficacy and the biochemical potential to remove various pollutants. However, physico-chemical factors can influence the biofilm community significantly, causing performance disturbances. Therefore, we decided to examine the structure of microbial community in rotating biological contactor (RBC) biofilm during coke wastewater treatment and to investigate the possible shift in the community structure caused by the feeding medium change from synthetic to real coke wastewater. The experiment performed with high-throughput next-generation sequencing (NGS) revealed that bacteria commonly present in wastewater treatment plant (WWTP) systems, responsible for nitrite oxidizing, such as Nitrospira or Nitrobacter, were absent or below detection threshold, while Nitrosomonas, responsible for ammonia oxidizing, was detected in a relatively small number especially after shift to real coke wastewater. This research indicates that medium change could cause the change from autotrophic into heterotrophic nitrification led by Acinetobacter. Moreover, biofilm systems can be also a potential source of bacteria possessing high biochemical potential for pollutants removal but less known in WWTP systems, as well as potentially pathogenic microorganisms.
显示更多 [+] 显示较少 [-]Ball-milled biochar for alternative carbon electrode 全文
2019
Lyu, Honghong | Yu, Zebin | Gao, Bin | He, Feng | Huang, Jun | Tang, Jingchun | Shen, Boxiong
Ball-milled biochars (BM-biochars) were produced through ball milling of pristine biochars derived from different biomass at three pyrolysis temperatures (300, 450, and 600 °C). The results of scanning electron microscopic (SEM), surface area, hydrodynamic diameter test, and Fourier transform infrared spectroscopy (FTIR) revealed that BM-biochars had smaller particle size (140–250 nm compared to 0.5–1 mm for unmilled biochar), greater stability, and more oxygen-containing functional groups (2.2–4.4 mmol/g compared to 0.8–2.9 for unmilled biochar) than the pristine biochars. With these changes, all the BM-biochar-modified glassy carbon electrodes (BM-biochar/GCEs) exhibited prominent electrochemical properties (e.g., ΔEₚ of 119–254 mV compared to 850 mV for bare GCE). Cyclic voltammetry (CV) and electrochemical impedance spectra (EIS) show that ball-milled 600 °C biochar/GCE (BMBB600/GCE and BMBG600/GCE) had the smallest peak-to-peak separation (ΔEₚ = 119 and 132 mV, respectively), series resistance (RS = 88.7 and 89.5 Ω, respectively), and charge transfer resistance (RCT = 1224 and 1382 Ω, respectively), implying its best electrocatalytic activity for the reduction of Fe(CN)₆³⁻. It is supposed that the special structure (i.e., internal surface area, pore volume, oxygen-containing functional groups, and graphitic structure) facilitates the electron transfer and reduces interface resistance. Economic cost of BM-biochar/GCE was 1.97 × 10⁻⁷ USD/cm², much lower than that of a “low-cost platinum electrode” (0.03 USD/cm²). The results indicate potential application of the novel BM-biochar for low cost and high efficient electrodes. Graphical abstract
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