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Spatial distribution and pollution assessment of heavy metals in urban soils from southwest China 被引量:100
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作者 Guanghui Guo fengchang wu +1 位作者 Fazhi Xie Ruiqing Zhang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2012年第3期410-418,共9页
To identify the concentrations and sources of heavy metals, and to assess soil environmental quality, 63 soil samples were collected in Yibin City, Sichuan Province, China. Mean concentrations of As, Pb, Zn, and Cu we... To identify the concentrations and sources of heavy metals, and to assess soil environmental quality, 63 soil samples were collected in Yibin City, Sichuan Province, China. Mean concentrations of As, Pb, Zn, and Cu were 10.55, 61.23, 138.88 and 56.35 mg/kg, respectively. As concentrations were comparable to background values, while Pb, Zn, and Cu concentrations were higher than their corresponding background values. Industrial areas exhibited the highest concentrations of As, Pb, Zn, and Cu, while the lowest concentrations occurred in parks. Statistical analysis was performed and two cluster groups of metals were identified with Pb, Zn, and Cu in one group and As in the other. Spatial distribution maps indicated that Pb, Zn, and Cu were mainly controlled by anthropogenic activities, whereas As could be mainly accounted for by soil parent materials. Pollution index values of As, Pb, Zn, and Cu varied in the range of 0.24-1.93, 0.66-7.24, 0.42-4.19, and 0.62-5.25, with mean values of 0.86, 1.98, 1.61, and 1.78, respectively. The integrated pollution index (IPI) values of these metals varied from 0.82 to 3.54, with a mean of 1.6 and more than 90% of soil samples were moderately or highly contaminated with heavy metals. The spatial distribution of IPI showed that newer urban areas displayed relatively lower heavy metal contamination in comparison with older urban areas. 展开更多
关键词 urban soils heavy metals pollution assessment spatial distribution
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Removal of antimony from antimony mine flotation wastewater by electrocoagulation with aluminum electrodes 被引量:19
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作者 Jing Zhu fengchang wu +2 位作者 Xiangliang Pan Jianyang Guo Dongsheng Wen 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2011年第7期1066-1071,共6页
Antimony (Sb) has received increasing environmental concerns due to its potential toxic and carcinogenic properties. In the present work, the electrocoagulation technique was used to treat the flotation wastewater f... Antimony (Sb) has received increasing environmental concerns due to its potential toxic and carcinogenic properties. In the present work, the electrocoagulation technique was used to treat the flotation wastewater from a heavy antimony polluted area, and the mechanism of removing Sb was also investigated. The study focused on the effect of operation parameters such as current density, initial pH and standing time on the Sb removal efficiency. Antimony concentration of below 1 mg/L in the treated wastewater was achieved, which meets the emission standards established by State Department of Environmental Protection and State Administration of China for Quality Supervision and Inspection and Quarantine of China. 展开更多
关键词 ANTIMONY ELECTROCOAGULATION sodium butyl xanthate aluminum
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A review of environmental characteristics and effects of low-molecular weight organic acids in the surface ecosystem 被引量:12
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作者 Min Xiao fengchang wu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2014年第5期935-954,共20页
Low molecular weight organic acids (LMWOAs) are prevalent on the earth's surface. They are vital intermediate products during metabolic pathways of organic matter and participate in the tricarboxylic acid cycle dur... Low molecular weight organic acids (LMWOAs) are prevalent on the earth's surface. They are vital intermediate products during metabolic pathways of organic matter and participate in the tricarboxylic acid cycle during life activities. Photochemical reactions are pivotal for LMWOAs' origination and play a large role in determining their diversity and their ultimate fate. Within the long time that organic matter is preserved in sediments, it can be decomposed and converted to release organic and inorganic pollutants as well as C, N, and P nutrients, which are of potential ecological risk in causing secondary pollution to lake water. The sediment pool is a comprehensive and complex compartment closely associated with overlying water by various biochemical processes, during which LMWOAs play critical roles to transport and transform elements. This article elucidates geochemical behaviors of LMWOAs in the surface environment in details, taking natural water, soil, and aerosol as examples, focusing on reviewing research developments on sources and characteristics, migration and mineralization of LMWOAs and relevant environmental effects. Simultaneously, this review article depicts the categories and contents of LMWOAs or their contribution to DOC in environmental media, and evaluates their importance during organic matter early diagenesis. Through concluding and discussing the conversion mechanisms and influencing factors, the next research orientations on LMWOAs in lake ecosystems are determined, mainly concerning relationships with hydrochemical parameters and microorganisms, and interactions with pollutants. This will enrich the knowledge on organic matter degradation and related environmental effects, and help reconstruct a theoretical framework for organic compound succession and influencing factors, providing basic data for lake eutrophication and ecological risk assessment, conducive to better control over water pollution and proper management of water quality. 展开更多
关键词 low molecular weight organic acids conversion mechanism POLLUTANTS environmental effects ecological risk management of water quality
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Fluorescence regional integration and differential fluorescence spectroscopy for analysis of structural characteristics and proton binding properties of fulvic acid sub-fractions 被引量:13
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作者 Fanhao Song fengchang wu +8 位作者 Weiying Feng Zhi Tang John P.Giesy Fei Guo Di Shi Xiaofei Liu Ning Qin Baoshan Xing Yingchen Bai 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2018年第12期116-125,共10页
Structural characteristics and proton binding properties of sub-fractions(FA3–FA13) of fulvic acid(FA), eluted stepwise by pyrophosphate buffer were examined by use of fluorescence titration combined with fluores... Structural characteristics and proton binding properties of sub-fractions(FA3–FA13) of fulvic acid(FA), eluted stepwise by pyrophosphate buffer were examined by use of fluorescence titration combined with fluorescence regional integration(FRI) and differential fluorescence spectroscopy(DFS). Humic-like(H-L) and fulvic-like(F-L) materials, which accounted for more than 80% of fluorescence response, were dominant in five sub-fractions of FA. Based on FRI analysis, except the response of F-L materials in FA9 and FA13, maximum changes in percent fluorescence response were less than 10% as pH was increased from 2.5 to 11.5.Contents of carboxylic and phenolic groups were compared for fluorescence peaks of FA sub-fractions based on pH-dependent fluorescence derived from DFS. Static quenching was the dominant mechanism for binding of protons by FA sub-fractions. Dissociation constants(p Ka) were calculated by use of results of DFS and the modified Stern-Volmer relationship. The p Kaof H-L, F-L, tryptophan-like and tyrosine-like materials of FA subfractions exhibited ranges of 3.17–4.06, 3.12–3.97, 4.14–4.45 and 4.25–4.76, respectively, for acidic pHs. At basic pHs, values of p Ka for corresponding materials were in ranges of 9.71–10.24, 9.62–10.99, 9.67–10.31 and 9.33–10.28, respectively. At acidic pH, protein-like(P-L)materials had greater affinities for protons than did either H-L or F-L materials. The dicarboxylic and phenolic groups were likely predominant sites of protonation for both H-L and F-L materials at both acidic and basic pHs. Amino acid groups were significant factors during proton binding to protein-like materials of FA sub-fractions at basic pH. 展开更多
关键词 Fluorescence titration PROTONATION Modified Stern-Volmer equation Dissociation constant BINDING
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Phosphorus speciation in the sediment profile of Lake Erhai, southwestern China: Fractionation and ^(31)P NMR 被引量:7
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作者 Runyu Zhang Liying Wang +1 位作者 fengchang wu Baoan Song 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2013年第6期1124-1130,共7页
The distribution characteristics of phosphorus (P) forms in the sediment profile of Lake Erhai, in southwestern China has been investigated by sequential extraction and 31p nuclear magnetic resonance spectroscopy (... The distribution characteristics of phosphorus (P) forms in the sediment profile of Lake Erhai, in southwestern China has been investigated by sequential extraction and 31p nuclear magnetic resonance spectroscopy (NMR) of NaOH extracts to understand P dynamics and its potential contribution to lake eutrophication. Contents of P fractions varied in the order of NH4C1 extracted P (NH4C1- P) 〈 bicarbonate-dithionite extracted P (BD-P) 〈 HC1-P, Residual-P 〈 NaOH extracted P (NaOH-P). The highly available NH4C1-P represented less than 1% of total P (TP). BD-P and NaOH extracted reactive P (NaOH-rP) averaged 39%, while the ratio of Fe/P was higher than 15, indicating low P release from the sediments under permanent oxic condition. The less bio-available HC1-P, NaOH extracted nonreactive P (NaOH-nrP) and residual-P contributed 61% of TP. Regression analysis revealed that BD-P, NaOH-rP and HC1-P were positively correlated with the contents of Fe and Mn, A1 and Fe, and Ca, respectively. The investigation of P compound groups in NaOH extracts by 31p NMR showed that ortho-P and monoester-P were the largest two constituents of the P pool, followed by diester-P, phosphonate and pyro-P. A comparison of vertical variations of P groups in the sediment profile suggested that these compounds were involved in the P recycling to different extents in Lake Erhai. In particular, the lake exhibits high potential for labile P release from the surface sediments, which should be taken into consideration even after the outsourced P runoff ceased. 展开更多
关键词 phosphorus SPECIATION FRACTIONATION 31p NMR SEDIMENT EUTROPHICATION
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Development of methods for establishing nutrient criteria in lakes and reservoirs: A review 被引量:8
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作者 Shouliang Huo Chunzi Ma +3 位作者 Beidou Xi Yali Zhang fengchang wu Hongliang Liu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2018年第5期54-66,共13页
Nutrient criteria provide a scientific foundation for the comprehensive evaluation, prevention,control and management of water eutrophication. In this review, the literature was examined to systematically evaluate the... Nutrient criteria provide a scientific foundation for the comprehensive evaluation, prevention,control and management of water eutrophication. In this review, the literature was examined to systematically evaluate the benefits, drawbacks, and applications of statistical analysis,paleolimnological reconstruction, stressor-response model, and model inference approaches for nutrient criteria determination. The developments and challenges in the determination of nutrient criteria in lakes and reservoirs are presented. Reference lakes can reflect the original states of lakes, but reference sites are often unavailable. Using the paleolimnological reconstruction method, it is often difficult to reconstruct the historical nutrient conditions of shallow lakes in which the sediments are easily disturbed. The model inference approach requires sufficient data to identify the appropriate equations and characterize a waterbody or group of waterbodies, thereby increasing the difficulty of establishing nutrient criteria. The stressor-response model is a potential development direction for nutrient criteria determination, and the mechanisms of stressor-response models should be studied further. Based on studies of the relationships among water ecological criteria, eutrophication, nutrient criteria and plankton, methods for determining nutrient criteria should be closely integrated with water management requirements. 展开更多
关键词 Nutrient criteria Statistical analysis approach Paleolimnological reconstructionapproach Stressor-response model Model inference approach
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Three decades of changes in water environment of a large freshwater Lake and its relationship with socio-economic indicators 被引量:5
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作者 Cuicui Li Weiying Feng +5 位作者 Fanhao Song Zhongqi He fengchang wu Yuanrong Zhu John P.Giesy Yingchen Bai 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2019年第3期156-166,共11页
Tai Lake(Ch: Taihu) has attracted international attention forcyanobacteria blooms.However, the drivers of cultural eutrophication, especially long-term socio-economic indicators have been little researched. The result... Tai Lake(Ch: Taihu) has attracted international attention forcyanobacteria blooms.However, the drivers of cultural eutrophication, especially long-term socio-economic indicators have been little researched. The results of research demonstrate how socioeconomic development affected quality of water and how it has been improved by anthropogenic activities. This study described variability in indicators of water quality in Tai Lakeand investigated thedrivers. Significant relationships existed between concentrations of annual mean total nitrogen(TN), total phosphorous(TP), chemical oxygen demand(COD) and biological oxygen demand(BOD), and population, per capital gross domestic production(GDP) and sewage discharge(p < 0.05). However, mechanisms causing change varied among TN, TP, COD and BOD. Before 2000, the main contributors to increases in concentrations of TN were human population, GDP and volumes of domestic sewage discharges. After 2000, discharges of industrial sewage become the primary contributor. After 1998, the regressions of annual mean TN, TP and COD on per capital GDP, population and domestic sewage discharge were reversed compared to the former period. Since 1999, an apparent inverted U-shaped relationship between environmental pollution and economic development has developed, which indicated that actions taken by governments have markedly improved quality of water in Tai Lake. The statistical relationship between BOD and per capital GDP didn't conform to the Kuznet curve. The Ushaped Kuznet curve may offer hope for the future that with significant environmental investments a high GDP can be reached and maintained without degradation of the environment, especially through appropriate management of industrial sewage discharge. 展开更多
关键词 EUTROPHIC lake Water environment INDICATORS Population GDP SEWAGE discharge ASIA
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Sedimentary record of polycyclic aromatic hydrocarbons in Lake Erhai,Southwest China 被引量:6
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作者 Jianyang Guo Zhang Liang +3 位作者 Haiqing Liao Zhi Tang Xiaoli Zhao fengchang wu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2011年第8期1308-1315,共8页
The temporal distribution of polycyclic aromatic hydrocarbons (PAHs) was investigated in a sediment core from Lake Erhai in Southwest China using gas-chromatography/mass spectrometry (GC/MS) method. The total orga... The temporal distribution of polycyclic aromatic hydrocarbons (PAHs) was investigated in a sediment core from Lake Erhai in Southwest China using gas-chromatography/mass spectrometry (GC/MS) method. The total organic carbon (TOC) normalized total PAHs concentrations (sum of US Environmental Protection Agency proposed 16 priority PAHs) ranged from 31.9 to 269 ixg/g dry weight (dw), and were characterized by a slowly increasing stage in the deeper sediments and a sharp increasing stage in the upper sediments. The PAHs in the sediments were dominated by low molecular weight (LMW) PAHs, suggesting that the primary source of PAHs was low- and moderate temperature combustion processes. However, both the significant increase in high molecular weight (HMW) PAHs in the upper sediments and the vertical profile of diagnostic ratios pointed out a change in the sources of PAHs from low-temperature combustion to high-temperature combustion. The ecotoxicological assessment based on consensus-based sediment quality guidelines implied that potential adverse biological impacts were possible for benzo(ghi)perylenelene and most LMW PAHs. In addition, the total BaP equivalent quotient of seven carcinogenic polycyclic aromatic hydrocarbons (BaA, CHr, BbF, BkF, BaP, DBA and INP) was 106.1 rig/g, according to the toxic equivalency factors. Although there was no great biological impact associated with the HMW PAils, great attention should be paid to these PAH components based on their rapid increase in the upper sediments. 展开更多
关键词 polycyclic aromatic hydrocarbons sediment core Lake Erhai risk assessment Southwest China
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Characteristics and distribution of low molecular weight organic acids in the sediment porewaters in Bosten Lake, China 被引量:7
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作者 Min Xiao fengchang wu +3 位作者 Haiqing Liao Wen Li Xinqing Lee Rongsheng Huang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第3期328-337,共10页
The composition and vertical profiles of low molecular-weight organic acids (LMWOAs) and the contribution of them to dissolved organic matter (DOM) in sediment porewaters in Bosten Lake, Xinjiang, China were inves... The composition and vertical profiles of low molecular-weight organic acids (LMWOAs) and the contribution of them to dissolved organic matter (DOM) in sediment porewaters in Bosten Lake, Xinjiang, China were investigated. The results showed that total concentration of LMWOAs was up to 94.5 μmol/L and their proportion in DOM was 5.6%, suggesting that LMWOAs were important chemical components in DOM in lake sediment porewaters. Among the seven LMWOAs, pyruvic and acetic acid had the highest concentrations with 26.30 and 8.31 μmol/L, accounting for 51.4% and 14.92% of LMWOAs, respectively. Trifluoroacetic and sorbic acid had the lowest concentrations, indicating that the compositions of LMWOAs in relative reducing environments were largely different from those reported in glacier, atmosphere and soils. The concentrations of lactic, acetic, formic, sorbic and oxalic acid decreased with increasing depth, probably relating to stronger microbial activities in the initial stage of early diagenesis. Trifluoroacetic acid was mainly anthropogenic with its concentration, showing a diusive trend from the surface to bottom sediments. The concentrations of lactic acid and nitrate generally showed a consistent profile. The increasing concentration of pyruvic acid in the vertical profile was just opposite to that of sulfate, revealing a significant negative relationship between them. Oxalic acid remained constant except for an obvious peak at 6 cm depth. The results indicated the diversities in sources and behaviors for various LMWOAs during early diagenesis in sediments. 展开更多
关键词 dissolved organic matter low molecular-weight organic acids sediment porewaters early diagenesis
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A Historical Sedimentary Record of Mercury in a Shallow Eutrophic Lake: Impacts of Human Activities and Climate Change 被引量:6
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作者 Hanxiao Zhang Shouliang Huo +3 位作者 Kevin M. Yeager Beidou Xi Jingtian Zhang fengchang wu 《Engineering》 SCIE EI 2019年第2期296-304,共9页
Mercury and its derivatives are hazardous environmental pollutants and could affect the aquatic ecosystems and human health by biomagnification. Lake sediments can provide important historical information regarding ch... Mercury and its derivatives are hazardous environmental pollutants and could affect the aquatic ecosystems and human health by biomagnification. Lake sediments can provide important historical information regarding changes in pollution levels and thus trace anthropogenic or natural influences. This research investigates the 100-year history of mercury (Hg) deposition in sediments from Chao Lake, a shallow eutrophic lake in China. The results indicate that the Hg deposition history can be separated into three stages (pre-1960s, 1960s–1980s, and post-1980s) over the last 100 years. Before the 1960s, Hg concentrations in the sediment cores varied little and had no spatial difference. Since the 1960s, the concentration of Hg began to increase gradually, and showed a higher concentration of contamination in the western half of the lake region than in the eastern half of the lake region due to all kinds of centralized human-input sources. The influences of anthropogenic factors and hydrological change are revealed by analyzing correlations between Hg and heavy metals (Fe, Co, Cr, Cu, Mn, Pb, and Zn), stable carbon and nitrogen isotopes (d13C and d15N), nutrients, particle sizes, and meteorological factors. The results show that Hg pollution intensified after the 1960s, mainly due to hydrological change, rapid regional development and urbanization, and the proliferation of anthropogenic Hg sources. Furthermore, the temperature, wind speed, and evaporation are found to interactively influence the environmental behaviors and environmental fate of Hg. 展开更多
关键词 LAKE sediment MERCURY Vertical distribution ANTHROPOGENIC activities
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Enlightenment from the COVID-19 Pandemic:The Roles of Environmental Factors in Future Public Health Emergency Response 被引量:4
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作者 Xiaolei Wang fengchang wu +6 位作者 Xiaoli Zhao Xiao Zhang Junyu Wang Lin Niu Weigang Liang Kenneth Mei Yee Leung John P.Giesy 《Engineering》 SCIE EI 2022年第1期108-115,共8页
The coronavirus disease 2019(COVID-19)pandemic is challenging the current public health emergency response systems(PHERSs)of many countries.Although environmental factors,such as those influencing the survival of viru... The coronavirus disease 2019(COVID-19)pandemic is challenging the current public health emergency response systems(PHERSs)of many countries.Although environmental factors,such as those influencing the survival of viruses and their transmission between species including humans,play important roles in PHERSs,little attention has been given to these factors.This study describes and elucidates the roles of environmental factors in future PHERSs.To improve countries’capability to respond to public health emergencies associated with viral infections such as the COVID-19 pandemic,a number of environmental factors should be considered before,during,and after the responses to such emergencies.More specifically,to prevent pandemic outbreaks,we should strengthen environmental and wildlife protection,conduct detailed viral surveillance in animals and hotspots,and improve early-warning systems.During the pandemic,we must study the impacts of environmental factors on viral behaviors,develop control measures to minimize secondary environmental risks,and conduct timely assessments of viral risks and secondary environmental effects with a view to reducing the impacts of the pandemic on human health and on ecosystems.After the pandemic,we should further strengthen surveillance for viruses and the prevention of viral spread,maintain control measures for minimizing secondary environmental risks,develop our capability to scientifically predict pandemics and resurgences,and prepare for the next unexpected resurgence.Meanwhile,we should restore the normal life and production of the public based on the“One Health”concept,that views global human and environmental health as inextricably linked.Our recommendations are essential for improving nations’capability to respond to global public health emergencies. 展开更多
关键词 Public health emergency Public health emergency response system Environmental factors Prevention and control Viral infections
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Molecular diversity of arbuscular mycorrhizal fungi at a large-scale antimony mining area in southern China 被引量:8
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作者 Yuan Wei Zhipeng Chen +6 位作者 fengchang wu Hong Hou Jining Li Yuxian Shangguan Juan Zhang Fasheng Li Qingru Zeng 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2015年第3期18-26,共9页
Arbuscular mycorrhizal fungi (AMF) have great potential for assisting heavy metal hyperaccumulators in the remediation of contaminated soils. However, little information is available about the community composition ... Arbuscular mycorrhizal fungi (AMF) have great potential for assisting heavy metal hyperaccumulators in the remediation of contaminated soils. However, little information is available about the community composition of AMF under natural conditions in soils contaminated by antimony (Sb). The objective of this study was to investigate the characteristics of AMF molecular diversity, and to explore the effects of Sb content and soil properties on the AMF community structure in an Sb mining area. Four Sb mine spoils and one adjacent reference area were selected from around the Xikuangshan mine in southern China. The association of AMF molecular diversity and community composition with the rhizosphere soils of the dominant plant species was studied by Polymerase Chain Reaction-Denaturing Gradient Gel Electrophoresis (PCR-DGGE). Results from all five studied sites showed that the diversity of AMF decreased with increasing Sb concentration. Principal component analysis (PC_A) indicated that the AMF community structure was markedly different among these groups. Further redundancy analysis (RDA) showed that Sb contamination was the dominating factor influencing the AMF community structure in the Sb mine area. However, the multivariate analysis showed that, apart from the soil Sb content, extractable nitrogen content and organic matter content also attributed to AMF sequence distribution type. Some AMF sequences were only found in the highly contaminated area and these might be ideal candidates for improving phytoremediation efficiency in Sb mining regions. Gene sequencing analysis revealed that most species were affiliated with Gloraus, suggesting that Glomus was the dominant AMF genus in the studied Sb mining area. 展开更多
关键词 Antimony Arbuscular mycorrhizal fungi Molecular diversity Gommunity structure
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Mobility and sulfidization of heavy metals in sediments of a shallow eutrophic lake, Lake Taihu, China 被引量:8
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作者 Shouliang Huo Jingtian Zhang +4 位作者 Kevin M.Yeager Beidou Xi Yanwen Qin Zhuoshi He fengchang wu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2015年第5期1-11,共11页
The technique of DGT(diffusive gradients in thin films) using three diffusive gel thicknesses was applied to estimate the mobility and bioavailability of heavy metals in sediments and porewater of Lake Taihu, China.... The technique of DGT(diffusive gradients in thin films) using three diffusive gel thicknesses was applied to estimate the mobility and bioavailability of heavy metals in sediments and porewater of Lake Taihu, China. The DGT results showed significantly positive correlations between Co, Pb, Cd and Mn, and Ni and Fe concentrations in porewater. Cu and Zn showed a significantly negative correlation with Mn, due to Cu combination with carbonates and Zn derived from agricultural pollution, respectively. The rank order of average concentrations of Co, Ni and Cd at each station was DGT1.92〉DGT0.78〉 DGT0.39, suggesting stronger resupply from sediments to porewater when using thicker diffusive gels. Comparing centrifugation and DGT measurements, Co, Ni and Cd are highly labile; Mn and Fe are moderately labile; and Cu, Zn and Pb are slightly labile. The variations of AVS concentrations in sediment cores indicate that metal sulfides in deeper layers are easily diffused into surface sediments. 展开更多
关键词 Sulfidization process Heavy metals DGT(diffusive gradients in thin films)
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Historical records of polycyclic aromatic hydrocarbon deposition in a shallow eutrophic lake:Impacts of sources and sedimentological conditions 被引量:6
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作者 Chaocan Li Shouliang Huo +5 位作者 Zhiqiang Yu Wei Guo Beidou Xi Zhuoshi He Xiangying Zeng fengchang wu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2016年第3期261-269,共9页
Sediment core samples collected from Lake Chaohu were analyzed for 15 priority polycyclic aromatic hydrocarbons(PAHs)to assess the spatial and temporal distributions of the PAHs during lacustrine sedimentary process... Sediment core samples collected from Lake Chaohu were analyzed for 15 priority polycyclic aromatic hydrocarbons(PAHs)to assess the spatial and temporal distributions of the PAHs during lacustrine sedimentary processes and regional economic development.Assessing the PAH sedimentary records over an approximately 100-year time span,we identified two stages in the PAH inputs and sources(before the 1970 s and after the 1970s)in the eastern lake region near a village,whereas three stages(before the 1950 s,1950s–1990s and after the1990s)were identified in the western lake region near urban and industrial areas.Rapid increases in the PAH depositional fluxes occurred during the second stage due to increased human activities in the Lake Chaohu basin.The composition and isomeric ratios of the PAHs revealed that pyrolysis is the main source of PAHs in this lake.Strong positive relationships between PAH concentration and the total organic carbon concentration,sediment grain size(〈 4 μm),as well as the local population and Gross Domestic Product indicated that the sedimentary conditions impact the depositional characteristics of the PAHs;simultaneously,socioeconomic activities,such as energy consumption and the levels of urban industrialization and civilization,affect both the composition and abundance of the PAHs. 展开更多
关键词 PAHs Vertical distribution Flux Sedimentological impact Socioeconomic
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Investigation of low-molecular weight organic acids and their spatiotemporal variation characteristics in Hongfeng Lake,China 被引量:6
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作者 Min Xiao fengchang wu +2 位作者 Liying Wang Xinqing Li Rongsheng Huang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2013年第2期237-245,共9页
The identities and concentrations of low-molecular-weight organic acids (LMWOAs) were determined by ion chromatography throughout a 20-m water column in Hongfeng Lake, China. The spatiotemporal variations of LMWOAs ... The identities and concentrations of low-molecular-weight organic acids (LMWOAs) were determined by ion chromatography throughout a 20-m water column in Hongfeng Lake, China. The spatiotemporal variations of LMWOAs and their contributions to dissolved organic matter (DOM) in a research period of 24 hr were also investigated. The results demonstrated that five LMWOAs (lactic, acetic, pyruvic, sorbic, oxalic acid) were detected, and their total concentration and proportion in DOC were 6.55 μmol/L and 7.47%. Their average levels were 2.50, 0.65, 2.35, 0.96 and 0.09 μmol/L, respectively. LMWOAs were higher during daytime (10:00-18:00 on Jun 13, 2008) than nighttime (21:00-6:00 the next morning), in particular 4.99 μmol/L high in the epilimnion ( 1 m water depth), reflecting the fact that direct import from terrigenous sources and photochemical production from humic materials were dominant during LMWOAs' origin and accumulation. The same factors caused LMWOAs to be 0.63 μmol/L in the epilimnion higher than in the hypolimnion. The rapid decrease of total organic acid (TOA) up until 18:00 mainly resulted from bio-uptake and mineralization in the hypolimnion (〉1 m water depth). Pyruvic acid increased with time in the epilimnion and decreased in the hypolimnion, largely related to the two contrary processes of continuous degradation and synthesis of macromolecular organic matter during life materials' cycle mediated by organisms. Simultaneously, plankton behavior and thermal stratification played a pivotal role in LMWOAs' behavior in the water column, causing decreasing and increasing profiles. The distribution of LMWOAs represents an interesting resource for biogeochemical research of DOM in aquatic ecosystems. 展开更多
关键词 Hongfeng Lake low-molecular-weight organic acids photochemical production spatiotemporal variations thermal stratification
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Phosphorus speciation in surface sediments of a hypertrophic lake,Southwestern China:insights from fractionation and ^(31)P NMR 被引量:1
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作者 Runyu Zhang Liying Wang fengchang wu 《Chinese Journal Of Geochemistry》 EI CAS CSCD 2015年第2期167-176,共10页
Phosphorus(P) species in surface sediments from a shallow,hypertrophic lake,Lake Dianchi,China,were investigated by P fractionation and ^(31)P nuclear magnetic resonance(NMR) spectroscopy during a regional algal bloom... Phosphorus(P) species in surface sediments from a shallow,hypertrophic lake,Lake Dianchi,China,were investigated by P fractionation and ^(31)P nuclear magnetic resonance(NMR) spectroscopy during a regional algal bloom.In addition,their potential contributions to the overlying water were also evaluated.Labile fractions of P extracted by NH_4C1,bicarbonate dithionite and NaOH ranged from 340.6 to 1,725.8 mg kg^(-1),accounting for20.5%-67.2%of the total P.A two-step extraction method refinement of P recovery was performed before the^(31)P NMR analysis.Recovery rates of sedimentary TP and organic P,by combining EDTA pretreatment and NaOH or mixed reagents,ranged from 31.8%to 69.3%and from19.8%to 51.7%.^(31)P NMR results showed that ortho-P and monoester-P were the most abundant P components in the sediment extractable P of sediments,followed by diester-P and pyro-P.Spatial distribution of the sum of ortho-P,diester-P and pyro-P detected by P NMR corresponded well with the labile P concentration determined by fractionation.Both exhibited a significant positive correlation with the total P in the water column,suggesting that internal loading may be an important source of P for the lake ecosystem.Biogenic P other than ortho-P may contribute to phytoplankton growth,with the relative proportion being 4.4%-18.7%.The release of labile P fractions fueled algal bloom,and the decay of organic matter,following the bloom events,consumed oxygen and elevated the pH value.This co-dependence might lead to a vicious cycle.Transformation mechanisms of various P species remain ambiguous and are worthy of further investigation. 展开更多
关键词 表层沉积物 NMR分析 中国西南地区 湖泊生态系统 磷形态 分馏 肥大 连二亚硫酸钠
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Total concentrations and bioavailability of rare-earth elements in latesol in Hainan Province, China 被引量:1
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作者 Weihuang ZHU Yuangen YANG +2 位作者 fengchang wu Hua BI Qiang LIU 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期76-76,共1页
关键词 稀土元素 生物利用率 土壤 海南
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Adsorption of Ca2+on single layer graphene oxide 被引量:3
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作者 Amalia Terracciano Jianfeng Zhang +2 位作者 Christos Christodoulatos fengchang wu Xiaoguang Meng 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2017年第7期8-14,共7页
Graphene oxide(GO) holds great promise for a broad array of applications in many fields,but also poses serious potential risks to human health and the environment.In this study,the adsorptive properties of GO toward... Graphene oxide(GO) holds great promise for a broad array of applications in many fields,but also poses serious potential risks to human health and the environment.In this study,the adsorptive properties of GO toward Ca^(2+) and Na+were investigated using batch adsorption experiments,zeta potential measurements,and spectroscopic analysis.When pH increased from 4 to 9,Ca^(2+)adsorption by GO and the zeta potential of GO increased significantly.Raman spectra suggest that Ca^(2+)was strongly adsorbed on the GO via –COO Ca~+ formation.On the other hand,Na+was adsorbed into the electrical diffuse layer as an inert counterion to increase the diffuse layer zeta potential.While the GO suspension became unstable with increasing pH from 4 to 10 in the presence of Ca^(2+),it was more stable at higher pH in the NaC l solution.The findings of this research provide insights in the adsorption of Ca^(2+)on GO and fundamental basis for prediction of its effect on the colloidal stability of GO in the environment. 展开更多
关键词 Graphene oxide Calcium adsorption Raman spectra Colloidal stability
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Determination of Hg and MeHg complexation with dissolved organic matter by fluorescence quenching titration
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作者 Pingqing FU fengchang wu Feiyue WANG 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期264-265,共2页
关键词 甲基水银 溶解有机物 荧光性 水文科学 毒性
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Beyond animal testing:An integrated framework for modern chemical hazard identification and risk assessment
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作者 Tuantuan Fan Zhenfei Yan +1 位作者 Chenglian Feng fengchang wu 《Environmental Science and Ecotechnology》 2025年第6期18-20,共3页
The report“Making Peace with Nature:A scientific blueprint to tackle the climate,biodiversity and pollution emergencies,”released by the United Nations Environment Programme,highlights that the Earth is facing three... The report“Making Peace with Nature:A scientific blueprint to tackle the climate,biodiversity and pollution emergencies,”released by the United Nations Environment Programme,highlights that the Earth is facing three major crises:climate change,biodiversity loss,and environmental pollution[1].The Lancet Commission on pollution and health stated that 9 million people,representing one-sixth of global fatalities,died from pollution in 2019,among which more than 1.8 million deaths were caused by toxic chemical pollution[2]. 展开更多
关键词 risk assessment chemical hazard identification toxic chemical pol environmental pollution biodiversity loss toxic chemical pollution climate change
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