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1.
J Environ Manage ; 346: 118947, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37699289

RESUMO

Combined remediation technologies are increasingly being considered to uranium contaminated groundwater, such as the joint utilize of permeable reactive bio-barrier (Bio-PRB) and electrokinetic remediation (EKR). While the assessment of uranium plume evolution in the combined remediation system (CRS) have often been impeded by insufficient understanding of multi-physical field superposition. Therefore, advanced knowledge in multi-physical field coupling in groundwater flow will be crucial to the practical application of these techniques. A two-dimensional multi-physical field coupling model was constructed for predicting the uranium degradation in CRS. The study demonstrates that the coupling model is able to predict the uranium plume evolution and rapidly evaluate the performance of CRS components. The results show that field electric direction and flow field strength are the key factors that affect the retardation and remediation performance of CRS. The reverse electric field direction significantly affected the contact reaction time of uranium in the system. The uranium residence time in the reverse electric field was 3.8 d, which was significantly greater than the original electric field (2.0 d). Depending on the voltage, the reverse electric field direction was 16%-36% more efficient than the original direction. The strength of the flow field was about two orders of magnitude higher than that of the electric field, so the groundwater flow rate dominated remediation efficiency. Reducing the flow rate by 1/2 could improve the performance of the system by approximately 66%. In addition, the coupling model can be utilized to design standard CRS for real site of uranium contaminated groundwater. To meet the optimal performance, the direction of the electric field should be set opposite to the flow field. This work has successfully used a coupling model to predict uranium contaminant-plume evolution in CRS and estimate the performance of each component.

2.
Sci Total Environ ; 896: 165140, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37391144

RESUMO

Hyporheic zone (HZ) systems have a natural purification capacity, and they are commonly used to provide high quality drinking water. However, the presence of organic contaminants in HZ systems in anaerobic environments causes the aquifer sediments to release metals (e.g., Fe) at levels above drinking water standards, which affects the quality of groundwater. In this study, the effects of typical organic pollutants (dissolved organic matter (DOM)) on Fe release from anaerobic HZ sediments were investigated. Ultraviolet fluorescence spectroscopy, three-dimensional excitation-emission matrix fluorescence spectroscopy, excitation-emission matrix spectroscopy coupled with parallel factor analysis and Illumina MiSeq high-throughput sequencing were used to determine the effects of the system conditions on Fe release from HZ sediments. Compared with the control conditions (low traffic and low DOM as a baseline), the Fe release capacity was enhanced by 26.7 % and 64.4 % at low flow rate (85.8 m/d) and high organic matter concentration (1200 mg/L), which was consistent with the residence-time effect. The transport of heavy metals under different system conditions varied with the influent organic composition. The influent organic matter composition and fluorescence parameters (the humification index, biological index and fluorescence index) were closely related to the release of the Fe effluent, while these factors had less influence on Mn and As. From 16S rRNA analysis of the aquifer media at different depths at the end of the experiment, under low flow rate and high influent concentration conditions, reduction of Fe minerals by Proteobacteria, Actinobacteriota, Bacillus, and Acidobacteria promoted the release of Fe. These functional microbes play an active role in the Fe biogeochemical cycle in addition to reducing Fe minerals to promote Fe release. In summary, this study reveals the effects of the flow rate and influent DOM concentration on the release and biogeochemistry of Fe in the HZ. The results presented herein will contribute to a better understanding of the release and transport of common groundwater contaminants in the HZ and other groundwater recharge environments.


Assuntos
Água Potável , Água Subterrânea , Metais Pesados , Poluentes Químicos da Água , Matéria Orgânica Dissolvida , Água Potável/análise , RNA Ribossômico 16S , Metais Pesados/análise , Água Subterrânea/química , Poluentes Químicos da Água/análise
3.
Chemosphere ; 320: 138054, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36739984

RESUMO

Methyl parathion (MP) is a typical organophosphorus pesticide that is widely used worldwide, and hydrolysis, oxidation and reduction are the main abiotic degradation processes. Manganese dioxide (MnO2) and organic acid can participate in various geochemical processes of pollutants, a reaction system was constructed to degrade MP using δ-MnO2 and oxalic acid. The δ-MnO2/oxalic acid reaction system could efficiently degrade MP, and the removal rate of MP (20 µM) reached 67.83% within 30 h under the optimized conditions (pH 5, [δ-MnO2] = 2 mM, [oxalic acid] = 100 mM). MP was hydrolyzed by substitution reactions of SN@P and SN@C, and reduced by conversion of the nitro groups (-NO2) in MP and its hydrolysates to amino groups (-NH2). The primary active substance produced in the reaction system was the complexes dominated by Mn(III)-oxalic acid. This study provides a scientific basis for the degradation of organophosphorus pesticides using MnO2 and an organic acid. The results have important theoretical significance and application value for pollution control and remediation of organophosphorus pesticides.


Assuntos
Metil Paration , Praguicidas , Metil Paration/química , Óxidos/química , Compostos Organofosforados , Praguicidas/análise , Ácido Oxálico , Compostos de Manganês/química , Oxirredução , Cinética
4.
J Environ Manage ; 329: 117058, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36528944

RESUMO

Aquatic sediment polluted by potentially toxic elements (PTEs) from mining activities represents a potential health "time bomb" for humans and the local ecology, but the integrated analysis of pollution and hazards of PTEs in sediment around typical metal mines in China is limited. Presently, the associated pollution status, spatial distribution, and ecological and health hazards of Cd, Cu, Zn, Pb, Cr, and As were investigated through index evaluation, spatial analysis, health risk assessment models, and Monte Carlo simulation. Overall, the sediment exhibited varying degrees of PTE contamination; notably, the level of Cd was 104.85 times higher than its background value, and it became the most enriched element in the surveyed sediment, followed in descending order by Cu, As, Zn, Pb, and Cr. Nationally, over 64.5% of metal-mining-affected sediment presented a very high ecological risk, contributed mostly by Cd (43.2%-98.7%) followed by As, Pb, and Cu; the risk contributed by both Cr and Zn was found to be negligible. The adverse health risk posed to children by most sediment was 1.72 and 6.46 times higher than that posed to adults for cancerous and noncancerous risks, respectively. The potential noncarcinogenic risks were mainly caused by As, which contributed over 78.9% of the Hazard Index values, then followed by Pb (>9.3%). For both children and adults, the carcinogenic risk of PTEs decreased in the following order: As > Cd > Cr > Pb. The investigated sediment was found seriously affected by nearby metal mines, especially those in regions with long-term and large-scale nonferrous-metal-mining activities. This study could provide a reference for policymakers to develop control strategies for PTE pollution in sediment around mining areas.


Assuntos
Metais Pesados , Poluentes do Solo , Criança , Adulto , Humanos , Metais Pesados/análise , Monitoramento Ambiental , Cádmio , Chumbo , Solo , Poluentes do Solo/análise , China , Medição de Risco
5.
Artigo em Inglês | MEDLINE | ID: mdl-36498094

RESUMO

Heavy metals in the ocean exist in various media and assessing heavy metal pollution in the multimedia in seawater is important for proposing effective strategies to protect marine ecosystem health. However, comprehensive coastal pollution assessments and SSD-based assessments of heavy metals have been limited from an international perspective. This study discusses the distribution, sources, interactions, associated environmental factors, and potential ecological risks related to heavy metal pollution. To attain this objective, several tools and models were considered. The partition coefficient between sediment and water was used to understand the ability of heavy metals to be adsorbed from seawater by sediment. The water quality index was applied to evaluate the comprehensive heavy metal pollution at different sampling sites. The species diversity index was calculated by calculating the concentration of chlorophyll a. The geo-accumulation and potential ecological risk indexes were employed for the sediments' general pollution characteristic of heavy metals. Species sensitivity distribution was used for ecological risk evaluation. The results indicated that heavy metal pollution and ecological risk (Cu, Pb, Zn, Cd, As, Cr and Hg) are not serious, and the pollution conditions remain safe. Only Cu, Pb, and Hg concentrations in seawater exceed the Nation Class I Water Quality Standard. The concentrations of heavy metals showed significant spatial characteristics. Fisheries activities and industrial effluent discharges were identified as the main anthropogenic sources. This study provides a comprehensive assessment of heavy metals in multi-media, and the results will provide valuable information for nearshore ecological management and risk avoidance.


Assuntos
Mercúrio , Metais Pesados , Poluentes Químicos da Água , Monitoramento Ambiental , Ecossistema , Clorofila A , Poluentes Químicos da Água/análise , Medição de Risco , Metais Pesados/análise , China , Sedimentos Geológicos
6.
Artigo em Inglês | MEDLINE | ID: mdl-36231503

RESUMO

To better protect lacustrine ecologies and understand the evolutionary process of lake environments, it is critical to study the interacting mechanisms between lakes and the surrounding groundwater. The Wuliangsu Lake watershed is the largest wetland in the Yellow River basin and is the discharge area of the Hetao Irrigation District (HID), which is one of the three largest agricultural production areas in China. Due to the influence of human activities, the discharge water from the HID has led to the deterioration of the Wuliangsu Lake ecology and the degradation of the lake environment. Based on long-term observation data and water sampling data collected in 2021, a water-salt equilibrium model was used to analyze the recharge rate of groundwater to the lake. The contribution rate of groundwater to lake recharge in the study area was calculated with a Bayesian mixing model by combining D and 18O stable isotope data. Furthermore, the environmental evolutionary process of the lake was also analyzed using the collected water quality data. The results show that channel drainage was the main source of recharge to Wuliangsu Lake, accounting for more than 75%, while groundwater contributed less than 5% of lake recharge. After implementing the ecological water supplement plan, the concentration of various ions in the lake decreased, the concentration of the total dissolved solids (TDS) in the lake decreased from 1.7 g/L in 2016 to 1.28 g/L in 2021, and the ecological environment was improved. The contribution of groundwater to lake recharge was quantitatively analyzed. The results of this study can facilitate the development of vital strategies for preventing the further deterioration of lake water quality and for protecting wetland ecologies.


Assuntos
Água Subterrânea , Poluentes Químicos da Água , Teorema de Bayes , China , Monitoramento Ambiental/métodos , Água Subterrânea/análise , Humanos , Isótopos/análise , Lagos , Rios , Cloreto de Sódio/análise , Poluentes Químicos da Água/análise
7.
Sci Total Environ ; 836: 155725, 2022 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-35526625

RESUMO

Exploring the relationships between heavy metal release and salinity can help address the problems of combination of toxic heavy metals and salinization in contaminated soils. Therefore, in this study, the release characteristics of heavy metals (Cd, Cu and Zn) under different salt types and mass concentrations were investigated through batch desorption experiments. Spearman's correlation analysis was performed to assess the effects of typical physicochemical properties on metal release under salt stress. The results indicated that the types and concentration gradients of salt had notably different impacts on the release of different metals; specifically, there were significant impacts for Cd but slight impacts for Cu and Zn. MgCl2 and CaCl2 had more obvious promoting effects on Cd release, followed by a salt mixture and NaCl, and this pattern was similar for Zn release. Most salts could slightly restrain the release of Cu, except for MgCl2 and Na2SO4, which had slight promoting effects. Moreover, low levels of CaCl2 could effectively restrain the release of Cu. The results showed that the release capacities of metals followed the order of Cd > Cu > Zn, possibly attributed to the competitive adsorption among cations. Ferromanganese oxides in the soil favored the release of Cd and Zn under salt treatments, and redox potential was an important factor affecting Cu release. The results also suggested that the background values of metals could affect metal release, but the effects were varied under different salt treatments for Zn. The reason for this may be that the addition of different salts changed the effects of certain soil properties on the metal release. Overall, this study can serve as an important reference for controlling heavy metal pollution in soils in salinization and coastal areas.


Assuntos
Metais Pesados , Poluentes do Solo , Cádmio/análise , Cloreto de Cálcio , China , Monitoramento Ambiental , Metais Pesados/análise , Salinidade , Sais , Solo/química , Poluentes do Solo/análise , Zinco/análise
8.
Environ Res ; 204(Pt C): 112310, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34762928

RESUMO

90 groundwater samples and 14 surface water samples were collected in wet season (summer) and dry season (winter) in the North China Plain (NCP), and analyzed for 11 organophosphorus pesticides (OPPs). The results showed that the main types of OPPs in surface water and groundwater were dimethoate, dichlorvos, methyl-parathion, malathion in both summer and winter. The OPP concentrations in groundwater and surface water were higher in summer than in winter. In the vertical direction, the distribution characteristics of different four types of groundwater sampling points are different. In the horizontal direction: farmland adjacent to a river (FAR) > central farmland (CF) > nonfarm area adjacent to a river (NFAR) > central nonfarm area (CNF). The OPPs concentrations in surface water adjacent to farmland were higher than that in surface water adjacent to nonfarm area. The main factors influencing the distribution of OPPs in the groundwater and surface water were the interaction process between them, the groundwater flow field and the OPPs used in agricultural activities. The ecological risk of OPPs to surface water was greater in summer than in winter. Water Flea was at medium risk, and malathion had the greatest influence on Water Flea in both summer and winter. The non-carcinogenic and carcinogenic risks of the four main OPPs in surface water were higher than in groundwater, and were higher in summer than in winter, but they would not lead to adverse health effects on local residents.


Assuntos
Água Subterrânea , Praguicidas , Poluentes Químicos da Água , China , Monitoramento Ambiental/métodos , Compostos Organofosforados , Praguicidas/análise , Medição de Risco , Poluentes Químicos da Água/análise
9.
J Hazard Mater ; 411: 125125, 2021 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-33486225

RESUMO

Heavy metal pollution has been a global concern and key points of environmental pollution prevention and control due to the growing problems of urbanization and industrialization. Rapidly and correctly apportioning sources of heavy metal is still a great challenge because of the stability of source fingerprint and complex interaction of multiple contaminants and sources. In this study, we perform a combination of optimization of pollution source fingerprint and source apportionment through jointly utilizing two machine classification and screening methods for characterizing the pollution sources of heavy metal in the sediments of an urban river and its surrounding soils. Dominance-based rough set model (DRS), content optimization tools, and multivariate curve resolution-alternating least squares model (MCR-WALS) were employed to screen representative pollution source samples, optimize pollution source fingerprint, and apportion the potential sources of heavy metals, respectively. Further, Support vector machine (SVM) was adopted to correspondence analysis results and pollution fingerprint based on the factor characteristics for achieving source apportionment accurately. Results showed that the pollution source pollution source fingerprints optimized by DRS and optimization tools are more representative and stable, and the results obtained by SVM and MCR-WALS are more accurate comparing with traditional methods. As whole, source apportionment suggested that printing and dyeing, chemical, electroplating, metal processing were the main origins of heavy metals in this area and the proportions of them in sediment and soil pollution sources were 67.05% and 28.43%, respectively. Besides, coal combustion was also the main sources of heavy metal pollution in soils, accounting about 34.16%. Results of the study can advance our knowledge to better understand the characterization of heavy metal pollution in the peri-urban ecosystem and to design effective targeted strategies for reducing heavy metal pollution diffusion.

10.
J Environ Manage ; 281: 111874, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33385909

RESUMO

Surface-water irrigation is one of the most important irrigation methods in areas with abundant surface water. Although this method of irrigation is both economical and convenient, many contaminants are also introduced into the soil-water systems such as organophosphorus pesticides (OPPs). To study the influence of surface-water irrigation on the distribution of OPPs in soil-water systems, 42 water samples (38 groundwater and four surface water) and 85 soil samples (78 profile soil samples and seven topsoil samples) were taken from Shahu in the Jianghan Plain, China. Shahu is a typical Chinese surface-water irrigation district. During sampling, three types of areas were considered: surface-water irrigated areas, groundwater-irrigated areas away from rivers, and non-irrigated areas adjacent to rivers. The results showed that the concentrations of OPPs in the groundwater and soil in the surface-water irrigated farmland were higher than those in groundwater-irrigated farmland. The groundwater flow field and surface-water irrigation were responsible for the OPPs. Thus, it is clear that the surface-water irrigation had a strong influence on the distribution of OPPs in soil-water systems. Principal component analysis for OPPs content in groundwater showed that the key influencing factors on the distribution of OPPs in groundwater were the groundwater flow field and current pesticide use.


Assuntos
Água Subterrânea , Praguicidas , Poluentes Químicos da Água , Irrigação Agrícola , China , Monitoramento Ambiental , Praguicidas/análise , Solo , Água , Poluentes Químicos da Água/análise
11.
J Hazard Mater ; 407: 124796, 2021 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-33352419

RESUMO

Contaminated sites have been recognized as posing serious comprehensive social and environmental issues and have earned worldwide attention. China is becoming one of the largest contaminated sites remediation markets in the world and the contaminated sites in northeastern China need to rehabilitate urgently. However, remediation planning is often hindered by high financial costs resulting from incomplete assessments of pollution and inappropriate remediation plans. In-depth contaminated site assessments can provide the necessary baseline data for remediation alternatives screening. Therefore, risk assessments and remediation decisions will play crucial roles in the rehabilitation and reconstruction of contaminated sites in China. The main objectives of this study were to present a novel method for health risk assessment (HRA) and to demonstrate a multicriteria decision analysis (MCDA) based on this method to select the most suitable remediation alternatives of groundwater and to prioritize management of contaminated site. To demonstrate the HRA and MCDA processes, a typical contaminated site in Longtan, Jilin province, China, was used. The results of this research indicated that Benzene (PhH) and 1,2-Dichloroethylene (1,2-DCE) were the main organic pollutants and the vanillin plant in the north of the site was main pollution source. Pollution migrated from the north to the south and the health risk range in winter was significantly greater than in summer. Four remediation alternatives were proposed on the basis of the HRA results. The MCDA results showed that PRB was the most suitable technology for integrating the relevant environmental, social, economic, and technical aspects required for remediation. This study may help responsible agencies to strengthen local risk-based program screening frameworks for contaminated sites, to promote reconstruction projects, and to increase local public confidence of contaminated sites remediation.


Assuntos
Recuperação e Remediação Ambiental , Água Subterrânea , Petróleo , China , Poluição Ambiental , Petróleo/análise
12.
Ecotoxicol Environ Saf ; 208: 111524, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33129121

RESUMO

As one of the most widespread pollutants worldwide, nitrogen has long been a concern in the environment, including groundwater. However, due to the limitations of investigations and study progress, there is still a poor understanding of groundwater nitrogen pollution and its potential effects on human health in many areas, particularly in developing countries. The spatiotemporal evolution of groundwater nitrate nitrogen levels and potential human health risks in the Songnen Plain, Northeast China were comprehensively studied based on both our own test data and available published data that were collected by us over a study period from 1995 to 2015. Groundwater nitrate nitrogen concentrations exhibited significant temporal and spatial differences: there was an increasing trend with time; and the distribution of high concentration areas expanded from the central and western areas to the east with time. The similar pattern existed in the potential health risks posed to the residents considering the two exposure pathways including drinking water and dermal contact. The effects of groundwater nitrate nitrogen on human health depend on the nitrate concentration but there were also age differences, namely, in the order of infants > children > adult females ≈ adult males, according to the hazard quotient (HQ) used in the human health risk assessment (HHRA) model. The spatiotemporal evolution of groundwater nitrate nitrogen levels and potential human health risks indicate that the issue of nitrogen pollution in groundwater in the study area is worsening and needs further attention. The drivers that increased nitrate nitrogen concentrations in the groundwater of the study area were the increased fertilizer use due to the increased cultivated land area and implementation of a land fertility policy by the local government. It should be acknowledged that the results have uncertainties that not only come from the layout of sampling points and selection of spatial interpolation methods but also come from the parameter settings in the assessment model and assumptions of drinking water scenarios. However, the conclusions still have important reference value for groundwater pollution control and management and human health risk supervision and early warning.


Assuntos
Exposição Ambiental/estatística & dados numéricos , Nitratos/análise , Poluentes Químicos da Água/análise , Poluição Química da Água/estatística & dados numéricos , Criança , China , Água Potável/análise , Monitoramento Ambiental , Feminino , Fertilizantes , Água Subterrânea , Humanos , Lactente , Masculino , Nitrogênio/análise , Medição de Risco
13.
J Cell Mol Med ; 24(18): 10501-10511, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32705806

RESUMO

Andrographolide (Andro), a component from Chinese medicinal herb Andrographis paniculata, could alleviate pulmonary fibrosis in rodents. Yet, whether and how Andro mitigates epithelial-mesenchymal transition (EMT) induced by TGF-ß1 remain unknown. This study aimed to explore the effect of Andro on TGF-ß1-induced EMT in human alveolar epithelial cells (AECs) and the mechanisms involved. We illustrated that Andro inhibited TGF-ß1-induced EMT and EMT-related transcription factors in alveolar epithelial A549 cells. Andro also reduced TGF-ß1-induced cell migration and synthesis of pro-fibrotic factors (ie CCN-2, TGF-ß1), matrix metalloproteinases (ie MMP-2, MMP-9) and extracellular matrix (ECM) components (ie collagen 1), implying the inhibiting effect of Andro on TGF-ß1-induced EMT-like cell behaviours. Mechanistically, Andro treatment not only repressed TGF-ß1-induced Smad2/3 phosphorylation and Smad4 nuclear translocation, but also suppressed TGF-ß1-induced Erk1/2 phosphorylation and nuclear translocation in A549 cells. And treatment with ALK5 inhibitor (SB431542) or Erk1/2 inhibitors (SCH772984 and PD98059) remarkably reduced EMT evoked by TGF-ß1. In addition, Andro also reduced TGF-ß1-induced intracellular ROS generation and NOX4 expression, and elevated antioxidant superoxide dismutase 2 (SOD2) expression, demonstrating the inhibiting effect of Andro on TGF-ß1-induced oxidative stress, which is closely linked to EMT. Furthermore, Andro remarkably attenuated TGF-ß1-induced down-regulation of sirtuin1 (Sirt1) and forkhead box O3 (FOXO3), implying that Andro protects AECs from EMT partially by activating Sirt1/FOXO3-mediated anti-oxidative stress pathway. In conclusion, Andro represses TGF-ß1-induced EMT in AECs by suppressing Smad2/3 and Erk1/2 signalling pathways and is also closely linked to the activation of sirt1/FOXO3-mediated anti-oxidative stress pathway.


Assuntos
Células Epiteliais Alveolares/metabolismo , Diterpenos/farmacologia , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Fator de Crescimento Transformador beta1/farmacologia , Células A549 , Células Epiteliais Alveolares/efeitos dos fármacos , Antioxidantes/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Diterpenos/química , Regulação para Baixo/efeitos dos fármacos , Proteína Forkhead Box O3/metabolismo , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Oxidantes/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sirtuína 1/metabolismo , Proteínas Smad/metabolismo , Fatores de Transcrição/metabolismo
14.
Sci Total Environ ; 714: 136856, 2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-32018988

RESUMO

Bioenergy carbon capture and storage (BECCS) is an effective option for mitigation of greenhouse gas (GHG) emissions. Nevertheless, there is barely serious debate about whether its implementation can possibly jeopardize the global water resources security. Here, we provided an assessment of biomass-based Substitute Natural Gas (BioSNG) production combined with CCS, a promising BECCS technology, in terms of global water resources security, with a focus on the growth of two typical second-generation bioenergy crops: switchgrass and miscanthus. A bottom-up analysis approach was applied in this paper to calculating water consumption for BECCS and estimating water quality deterioration caused by increasing fertilizer and pesticide application. The results indicated that water usage of BECCS was equal to adding 12.86%-16.64% (switchgrass) and 17.59%-26.06% (miscanthus) additional water stress on global available water resources at 2100. Additional N fertilizer application in 2100 would be equal to over 84%, 55% and 42% for both switchgrass and miscanthus under three CCS capture efficiency scenarios, respectively, comparing to such global scale in 2012. Additional phosphate fertilizer adding to global annual available water at 2100 were 0.004-0.008 mg L-1 (switchgrass) and 0.003-0.006 mg L-1 (miscanthus), respectively. The secondary environmental hazards, such as N2O emission, would offset GHG emission mitigation by BECCS. Meanwhile, the enrichment and leaching of pesticide residues increased the risk of groundwater contamination. This study revealed water consumption and contamination issues caused by BECCS cannot be neglected. Thus, additional studies of accurate land-use models in global scale and advanced technology for biofuel extraction are needed in the future.


Assuntos
Água , Biocombustíveis , Biomassa , Carbono , Produtos Agrícolas
15.
Sci Total Environ ; 709: 136147, 2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-31905573

RESUMO

Groundwater level is an important variable in the evolution process of ecological environment systems. However, spatiotemporal changes in groundwater level are attributed to the comprehensive influence of natural and anthropogenic activities. Therefore, understanding the major driving forces to changes in spatiotemporal patterns of groundwater level is essential for sustainable utilization of regional groundwater and sustaining healthy ecosystems, especially in arid areas. In this study, based on monthly observations of depth to groundwater table (DTGT) from 67 monitoring wells during 2001-2010 in the Yichang Irrigation Sub-district (YISD) of the Hetao Irrigation District (HID), which is located in Northwest China with an arid climate, the empirical orthogonal function (EOF) method was used to analyze the spatiotemporal variations of DTGT and the major driving forces. The EOF analysis results showed that the first two spatial structures (EOF1 and EOF2) of DTGT were found in this region, which explained over 65% and 8% of the spatial variation of DTGT, respectively. Meteorological factors (evaporation and temperature) were the first leading factors to drive the temporal pattern of the first expansion coefficient (EC1) corresponding to the EOF1 at intra-annual scale as well as inter-annual scale. Particularly, temperature controlled the EC1 pattern during the freezing period from December to March. Soil texture was shown to have good correlations with the spatial patterns of DTGT, although these correlations diminished when the depth exceeded 250 cm. This study provides strong evidence that the principal spatiotemporal variations of groundwater can be effectively extracted by the EOF method, thereby obtaining integrated views of the relationships between the groundwater system and meteorological and anthropogenic factors.

16.
Sci Total Environ ; 707: 135601, 2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-31767320

RESUMO

The composition and distribution of microplastics in surface water of the Yellow River lower reach near estuary were investigated in this work. The major shape types of microplastics can be classified to fibers, fragments and particles, and 93.12% of microplastics in the surface water were fibers. The microplastics <200 µm were most abundant at all sample sites, which accounted for 87.94% of microplastics. The composition of microplastics was identified as polyethylene, polypropylene, and polystyrene according to infrared spectrometer analysis. The amounts of primary microplastics accounted for approximately three-fourths according to scanning electron microscope and microscope photo observing. The microplastics at different weathering processes could be also observed. The average abundances of microplastics in the dry and wet seasons were 930 and 497 item/L, respectively. The abundances of microplastics in the dry season all higher than that in the wet season. The microplastic concentrations in the surface water decreased linearly with the distances from the estuary of Yellow River with rather high positive correlation coefficients at wet season (r = 0.8104, p < .01) and at dry season (r = 0.8333, p < .01). The distribution of microplastics in the river section and the density of microplastics may be the primary factors to influence the microplastic concentrations in the surface water. The researches about distribution of microplastics in the river section might provide useful information that could be used for calculating either mass fluxes or inventories of microplastics.

17.
Toxicol Lett ; 321: 103-113, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31706003

RESUMO

Idiopathic pulmonary fibrosis (IPF) is a progressive lung disease with no effective medication. Andrographolide (Andro), extracted from Chinese herbal Andrographis paniculata, could attenuate bleomycin (BLM)-induced pulmonary fibrosis via inhibition of inflammation and oxidative stress, however, the anti-fibrotic mechanisms have not been clarified. Myofibroblasts are the primary cell types responsible for the accumulation of extracellular matrix (ECM) in fibrotic diseases, and targeting fibroblast proliferation and differentiation is an important therapeutic strategy for the treatment of IPF. Hence, this study aimed to investigate the effects of Andro on the fibroblast proliferation and differentiation in the in vivo and in vitro models. The results showed that Andro improved pulmonary function and inhibited BLM-induced fibroblast proliferation and differentiation and ECM deposition in the lungs. In vitro, Andro inhibited proliferation and induced apoptosis of TGF-ß1-stimulated NIH 3T3 fibroblasts and primary lung fibroblasts (PLFs). Andro also inhibited TGF-ß1-induced myofibroblast differentiation and ECM deposition in both cells. We also found that Andro suppressed TGF-ß1-induced Smad2/3 and Erk1/2 activation, suggesting that Smad2/3 and Erk1/2 inactivation mediates Andro-induced effects on TGF-ß1-induced fibroblast proliferation and differentiation. These results indicated that Andro has novel and potent anti-fibrotic effects in lung fibroblasts via inhibition of the proliferation and myofibroblast differentiation of fibroblasts and subsequent ECM deposition, which are modulated by TGF-ß1-mediated Smad-dependent and -independent pathways.


Assuntos
Bleomicina , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Diterpenos/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Fibrose Pulmonar Idiopática/prevenção & controle , Pulmão/efeitos dos fármacos , Miofibroblastos/efeitos dos fármacos , Proteínas Smad/metabolismo , Fator de Crescimento Transformador beta1/farmacologia , Animais , Apoptose/efeitos dos fármacos , Modelos Animais de Doenças , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/metabolismo , Matriz Extracelular/patologia , Fibrose Pulmonar Idiopática/induzido quimicamente , Fibrose Pulmonar Idiopática/metabolismo , Fibrose Pulmonar Idiopática/patologia , Pulmão/metabolismo , Pulmão/patologia , Masculino , Camundongos , Miofibroblastos/metabolismo , Miofibroblastos/patologia , Células NIH 3T3 , Ratos Sprague-Dawley , Transdução de Sinais
18.
Sci Total Environ ; 696: 133972, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31461695

RESUMO

Increasing anthropogenic contamination poses a significant threat to groundwater security. Identifying potential contamination sources and apportioning their corresponding contributions are of vital importance for the prevention of contamination and management of groundwater resources. In this study, principal component analysis (PCA), modified grey relational analysis (MGRA), absolute principal component score-multiple linear regression (APCS-MLR), and positive matrix factorization (PMF) receptor modeling technologies were employed to evaluate the groundwater quality and apportion the potential contamination sources in the Lalin river basin, a main grain production district in the northeast of China. The contamination assessment with PCA and MGRA suggested that the groundwater in Lalin river basin was polluted due to human activities. The PCA method identified five and four potential contamination sources in wet and dry seasons, respectively, and the main sources were basically same. The APCS-MLR and PMF methods apportioned the source contributions to each groundwater quality variable. The final results showed that agricultural sources including waste water, agrochemicals and fertilizers were identified as the main sources of groundwater contamination both in wet and dry seasons. In addition, groundwater management strategies learned from the advanced experiences were discussed to protect the groundwater system in that region.

19.
Environ Sci Pollut Res Int ; 26(24): 25235-25246, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31256394

RESUMO

We explored the effect of the presence or absence of humic acid (HA) on the sorption behaviour of Sr onto soil. We examined three different experimental cases for Sr sorption: (1) sorption in the presence of only colloidal HA, (2) sorption in the presence of only soil and (3) sorption in the presence of both colloidal HA and soil (HS). A batch technique was used to study the influencing factors, including the amount of colloidal HA, solid content, pH, initial concentration of Sr and contact time. The experiments showed that the influencing factors significantly affected the sorption process. For example, in the case of soil and HS, the sorption percentage increased rapidly with increasing solid content at m/V < 20 g/L, changing from 8.35% and 37.54% to 49.09% and 77.03%, respectively. Moreover, scanning electron microscopy and Fourier transform infrared spectroscopy were used to characterize samples. The kinetics and isotherms of Sr were best described by the pseudo-second-order and Langmuir models, which indicated that the process was controlled by chemisorption and uniform monolayer sorption with constant energy on the outer surface. These findings provide valuable information for predicting strontium migration in radioactive waste disposal sites.


Assuntos
Coloides/química , Substâncias Húmicas , Resíduos Radioativos/análise , Poluentes do Solo/química , Estrôncio/química , Instalações de Eliminação de Resíduos , Adsorção , Geologia , Cinética , Radioatividade , Solo/química , Poluentes do Solo/análise , Espectroscopia de Infravermelho com Transformada de Fourier
20.
Chemosphere ; 171: 635-643, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28056450

RESUMO

A detailed assessment of vanadium contamination characteristics in China was conducted based on the first national soil pollution survey. The map overlay analysis was used to evaluate the contamination level of vanadium and the non-carcinogenic risk assessment model was calculated to quantify the vanadium exposure risks to human health. The results showed that, due to the drastically increased mining and smelting activities, 26.49% of soils were contaminated by vanadium scattered in southwest of China. According to Canadian soil quality guidelines, about 8.6% of the national soil pollution survey samples were polluted, and pose high non-carcinogenic risks to the public, especially to children living in the vicinity of heavily polluted mining areas. We propose the area near the boundary of Yunnan, Guizhou, Guangxi, and Sichuan provinces as priority control areas due to their higher geochemical background or higher health risks posed to the public. Finally, recommendations for management are proposed, including minimization of contaminant inputs, establishing stringent monitoring program, using phytoremediation, and strengthening the enforcement of relevant laws. Therefore, this study provides a comprehensive assessment of soil vanadium contamination in China, and the results will provide valuable information for China's soil vanadium management and risk avoidance.


Assuntos
Poluentes do Solo/análise , Vanádio/análise , Adulto , Criança , China , Monitoramento Ambiental , Humanos , Metalurgia , Mineração , Medição de Risco , Solo
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