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Phosphorus speciation,transformation and benthic processes with implications for environmental impacts in the aquaculture area of Rushan Bay
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作者 Yao Feng Jun Liu +4 位作者 Aijun Zhang Yibin Wang Lu Wang Zongqing Lv Xiangbin Ran 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第8期99-112,共14页
Phosphorus(P)is an essential nutrient for many organisms in the ocean,which plays a central role in the stability of ecosystems and the evolution of the environment.The distribution,occurrence and source-sink process ... Phosphorus(P)is an essential nutrient for many organisms in the ocean,which plays a central role in the stability of ecosystems and the evolution of the environment.The distribution,occurrence and source-sink process of P in offshore waters are highly influenced by mariculture activities.P transformation in water-sediment system is the key process in P cycling,however,the mechanism is poorly documented in the coastal sea which is influenced by human activities.Based on the comprehensive surveys in the adjacent waters outside Rushan Bay in May,July and August 2014 and February 2015,the form and transformation of P in the suspended particulate matter(SPM)and surface sediment were analyzed.The results showed that contents of total P,authigenic P and organic P of SPM increased with the increase in distance from the shoreline off Rushan Bay,and the detrital-P decreased.The partition coefficient of P between water and SPM was related to the chemical activity of different forms of P,and a higher reactivity of inorganic P associated with SPM was observed.Hypoxia induced by mariculture changes the distribution and morphological composition of P in SPM and sediment in this typical aquaculture area,which can result in a conversion of sink to source of P in the sediment,thereby having a significant impact on the regional nutrient budget and associated with eutrophication. 展开更多
关键词 phosphorus speciation TRANSFORMATION benthic process AQUACULTURE Rushan Bay
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Differential utilization and speciation transformation of orthorhombic α-S_8 and amorphous μ-S by substrate-acclimated mesophilic Acidithiobacillus ferrooxidans 被引量:2
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作者 刘红昌 夏金兰 +3 位作者 聂珍媛 郑雷 马陈燕 赵屹东 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第9期3096-3102,共7页
The utilization and speciation transformation of α-S8 and μ-S by the typical mesophilic acidophilic strain Acidithiobacillus ferrooxidans ATCC 23270 were investigated.A.ferrooxidans cells first acclimated to the ene... The utilization and speciation transformation of α-S8 and μ-S by the typical mesophilic acidophilic strain Acidithiobacillus ferrooxidans ATCC 23270 were investigated.A.ferrooxidans cells first acclimated to the energy source α-S8 or μ-S,respectively.The results of cell growth and sulfur oxidation behavior showed that the strain grown on α-S8 entered slowly(about 1 d later) into the exponential phase,while grew faster in the exponential phase and attained higher maximal cell density and lower p H value than that on μ-S.After bio-corrosion,both of the two sulfur samples were evidently eroded and modified by A.ferrooxidans cells.After growth of A.ferrooxidans,the surface composition of amorphous μ-S became 63.1% μ-S and 36.9% α-S8,and that of orthorhombic α-S8 became 68.3% α-S8 and 31.7% μ-S,while the surface compositions of α-S8 and μ-S in sterile experiment were not changed,indicating that these two elemental sulfur species can be interconverted by A.ferrooxidans. 展开更多
关键词 sulfur utilization sulfur speciation transformation α-S8 μ-S Acidithiobacillus ferrooxidans
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Primary Speciation Analysis on 6 Kinds of Microelements in Glycyrrhiza uralensis Fisch. 被引量:1
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作者 梁新华 李梦菊 +1 位作者 王俊 郑彩霞 《Agricultural Science & Technology》 CAS 2010年第1期96-98,146,共4页
[Objective]The aim was to analyze the primary speciation of 6 microelements in Glycyrrhiza uralensis Fisch. and provide theoretical basis for explaining pharmacodynamic principle of liquorice and discussing quality co... [Objective]The aim was to analyze the primary speciation of 6 microelements in Glycyrrhiza uralensis Fisch. and provide theoretical basis for explaining pharmacodynamic principle of liquorice and discussing quality control of liquorice planting. [Method]The 6 elements Cu,Zn,Ca,Fe,Mg and Mn in roots of G.uralensis were extracted based on traditional decoction method and were separated into water-soluble state and suspension state by micro porous filtering film. The elements in water-soluble state were detected by flame atomic adsorption spectrophotometry (FAAS). [Result]The results showed that extractive rates of the elements were in the range of 1.71%-60.06%,and immerse-residue ratio in 0.018 3-1.682 0; the results also indicated that the immerse-residue ratio of Zn was biggest (1.68),Zn played an important medical role and might be considered as the best characteristic element in G.uralensis; the recoveries of the elements were ranged from 95.72% to 103.15% and relative standard deviations (RSD) were less than 2.38%. [Conclusion]Because of its high accuracy,FAAS method is feasible for analyzing primary speciation of microelements in G.uralensis. 展开更多
关键词 Glycyrrhiza uralensis Fisch. Microelement Flame atomic adsorption sepctrophotometry (FAAS) Primary speciation analysis
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Multilocus phylogeography and ecological niche modeling suggest speciation with gene flow between the two Bamboo Partridges 被引量:1
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作者 Pengcheng Wang Chiafen Yeh +6 位作者 Jiang Chang Hongyan Yao Yiqiang Fu Chengte Yao Xiao Wang Shouhsien Li Zhengwang Zhang 《Avian Research》 CSCD 2021年第2期227-236,共10页
Background:Understanding how species diversify is a long-standing question in biology.The allopatric speciation model is a classic hypothesis to explain the speciation process.This model supposes that there is no gene... Background:Understanding how species diversify is a long-standing question in biology.The allopatric speciation model is a classic hypothesis to explain the speciation process.This model supposes that there is no gene flow during the divergence process of geographically isolated populations.On the contrary,the speciation with gene flow model supposes that gene flow does occur during the speciation process.Whether allopatric species have gene flow during the speciation process is still an open question.Methods:We used the genetic information from 31 loci of 24 Chinese Bamboo Partridges(Bambusicola thoracicus)and 23 Taiwan Bamboo Partridges(B.sonorivox)to infer the gene flow model of the two species,using the approxi-mate Bayesian computation(ABC)model.The ecological niche model was used to infer the paleo-distribution during the glacial period.We also tested whether the two species had a conserved ecological niche by means of a back-ground similarity test.Results:The genetic data suggested that the post-divergence gene flow between the two species was terminated before the mid-Pleistocene.Furthermore,our ecological niche modeling suggested that their ecological niches were highly conserved,and that they shared an overlapping potential distribution range in the last glacial maximum.Conclusions:The allopatric speciation model cannot explain the speciation process of the two Bamboo Partridges.The results of this study supported a scenario in which speciation with gene flow occurring between the allopatric species and have contributed to our understanding of the speciation process. 展开更多
关键词 Allopatric speciation Bamboo Partridge EVOLUTION Reproductive isolation speciation with gene flow
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Transformation of mercury speciation through the SCR system in power plants 被引量:38
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作者 YANG Hong-min PAN Wei-ping 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第2期181-184,共4页
Coal-fired utility boilers are now identified as the largest source of mercury in the United States. There is speculation that the installation of selective catalytic reduction (SCR) system for reduction of NOx can ... Coal-fired utility boilers are now identified as the largest source of mercury in the United States. There is speculation that the installation of selective catalytic reduction (SCR) system for reduction of NOx can also prompt the oxidation and removal of mercury. In this paper, tests at six full-scale power plants with similar type of the SCR systems are conducted to investigate the effect of the SCR on the transformation of mercury speciation. The results show that the SCR system can achieve more than 70%-80% oxidation of elemental mercury and enhance the mercury removal ability in these units. The oxidation of elemental mercury in the SCR system strongly depends on the coal properties and the operation conditions of the SCR systems. The content of chloride in the coal is the key factor for the oxidization process and the maximum oxidation of elemental mercury is found when chloride content changes from 400 to 600 ppm. The sulfur content is no significant impact on oxidation of elemental mercury. 展开更多
关键词 electric utility boiler selective catalytic reduction mercury speciation OXIDATION
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Changes of Cu, Zn, and Cd speciation in sewage sludge during composting 被引量:15
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作者 GAO Ding ZHENG Guo-di CHEN Tong-bin LUO Wei GAO Wei ZHANG Yi-an LI Yan-xia 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第6期957-961,共5页
The potential toxicity risks from heavy metals depend on their chemical speciation. The four stages of the Tessier sequential extraction method were employed to investigate changes in heavy metal speciation (Cu, Zn, ... The potential toxicity risks from heavy metals depend on their chemical speciation. The four stages of the Tessier sequential extraction method were employed to investigate changes in heavy metal speciation (Cu, Zn, and Cd) of sewage sludge during forced aeration composting, and then to identify whether the composting process would reduce or enhance their toxicities. Throughout the composting process, the exchangeable, carbonate-bound, Fe-Mn oxide-bound, and organic matter-bound fractions of Cu were converted to the residual Cu fraction. The organic matter-bound Cu fraction greatly contributed to this transformation. Residual Zn fraction was transformed to the Fe-Mn oxide-bound and organic matter-bound fractions after composting. The residual Zn fraction was a major contributor to the organic matter-bound Zn fraction. The availability of Cu and Zn was reduced by composting such that the risk of heavy metal toxicity decreased with prolonged treatment times. Additionally, attention should be paid to the increased availability of Cd in sewage sludge after composting treatment. 展开更多
关键词 COMPOSTING distribution heavy metal sewage sludge speciation
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Influences of phosphate nutritional level on the phytoavailability and speciation distribution of cadmium and lead in soil 被引量:11
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作者 CHEN Su SUN Tie-heng +2 位作者 SUN Li-na ZHOU Qi-xing CHAO Lei 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2006年第6期1247-1253,共7页
A pot experiment was conducted to examine the influence of phosphate levels on the phytoavailability and speciation distribution of cadmium (Cd), lead (Pb) in soil. Spring wheat (Triticum aestivum L.) was select... A pot experiment was conducted to examine the influence of phosphate levels on the phytoavailability and speciation distribution of cadmium (Cd), lead (Pb) in soil. Spring wheat (Triticum aestivum L.) was selected as the tested plant. There were 5 phosphate fertilizer(Ca(H2PO4)2) levels including 0, 50, 100, 200, and 400 mg P2O5/kg soil, marked by P0, P1, P2, P3, and P4, respectively. CdCl2·2.5H2o and Pb(NO3)2 were added to soil as the following levels: Cd + Pb = 25+0, 0+1000, and 25+1000 mg/kg, marked by T1, T2, and T3, respectively. The results showed that the P fertilizer promoted the dry weight of wheat in all treatments and alleviated the contamination induced by Cd and Pb. With increasing levels of the additional P fertilizer, Cd concentration in different parts (root, haulm, chaffand grain) of wheat decreased at the P1 level at first and then increased. The soluble plus exchangeable (SE) fraction of Cd in soil decreased at the P1 level and then increased from P2 to P4 levels. The moderate P fertilizer reduced the phytoavailability of Cd. The application of P could obviously restrain the uptake of Pb by wheat and there were significantly negative correlations between the levels of P and the uptake of Pb. Phosphorus supply resulted in a decrease in the SE fraction of Pb and there was a significantly negative correlation between the levels of P and the SE fraction of Pb in soil. All the levels of the P fertilizer in this experiment could reduce the phytoavailability of Pb. Thus, it is feasible to apply the P fertilizer (Ca(H2PO4)2) to Pb contaminated soils. However, the levels of P application should be restricted in case that redundant P may increase the phytoavailability of Cd. 展开更多
关键词 PHOSPHATE PHYTOAVAILABILITY speciation distribution CADMIUM LEAD
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Speciation, distribution, and potential ecological risk assessment of heavy metals in Xiamen Bay surface sediment 被引量:11
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作者 LIN Cai LIU Yang +2 位作者 LI Wenquan SUN Xiuwu JI Weidong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2014年第4期13-21,共9页
Based on the survey of surface sediment in Xiamen Bay in October 2011, the speciation, distribution, and potential ecological risk assessment of heavy metals (Cu, Pb, Zn, Cd, and Cr) in this area were studied us-ing... Based on the survey of surface sediment in Xiamen Bay in October 2011, the speciation, distribution, and potential ecological risk assessment of heavy metals (Cu, Pb, Zn, Cd, and Cr) in this area were studied us-ing the sequential extraction method and ecological risk assessment method. The results indicated:(1) the total concentrations of these heavy metals were influenced by runoff, industrial wastewater, and sewage, and were all higher in the coastal area than the offshore area while the highest area of Pb was a little far-ther away from the coastal water due to atmosphere deposition;(2) sequential extractions suggested that Cu was mainly composed with residual and Fe/Mn-oxide bound fractions, Pb was bound to Fe/Mn-oxide, Zn and Cr were dominated by residual, and Cd bound to exchangeable and carbonate fractions; (3) the order of migration and transformation sequence was Cd&gt;Pb&gt;Cu&gt;Zn&gt;Cr and the degree of pollution was Cd&gt;Pb&gt;Cu&gt;Zn&gt;Cr;and (4) the ratios of the secondary and primary phases showed that Zn and Cr were both clean, Cu may be polluted, Pb was moderately polluted, while Cd was heavily polluted. 展开更多
关键词 Xiamen Bay heavy metals speciation DISTRIBUTION ecological risk
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Evaluation of mercury speciation and removal through air pollution control devices of a 190 MW boiler 被引量:14
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作者 Chengli Wu Yan Cao +3 位作者 Zhongbing Dong Chinmin Cheng Hanxu Li Weiping Pan 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第2期277-282,共6页
Air pollution control devices (APCDs) are installed at coal-fired power plants for air pollutant regulation. Selective catalytic reduction (SCR) and wet flue gas desulftLrization (FGD) systems have the co-benefi... Air pollution control devices (APCDs) are installed at coal-fired power plants for air pollutant regulation. Selective catalytic reduction (SCR) and wet flue gas desulftLrization (FGD) systems have the co-benefits of air pollutant and mercury removal. Configuration and operational conditions of APCDs and mercury speciation affect mercury removal efficiently at coal-fired utilities. The Ontario Hydro Method (OHM) recommended by the U.S. Environmental Protection Agency (EPA) was used to determine mercury speciation simultaneously at five sampling locations through SCR-ESP-FGD at a 190 MW unit. Chlorine in coal had been suggested as a factor affecting the mercury speciation in flue gas; and low-chlorine coal was purported to produce less oxidized mercury (Hg^2+) and more elemental mercury (Hg^0) at the SCR inlet compared to higher chlorine coal. SCR could oxidize elemental mercury into oxidized mercury when SCR was in service, and oxidation efficiency reached 71.0%. Therefore, oxidized mercury removal efficiency was enhanced through a wet FGD system. In the non-ozone season, about 89.5%-96.8% of oxidized mercury was controlled, but only 54.9%-68.8% of the total mercury was captured through wet FGD. Oxidized mercury removal efficiency was 95.9%-98.0%, and there was a big difference in the total mercury removal efficiencies from 78.0% to 90.2% in the ozone season. Mercury mass balance was evaluated to validate reliability of OHM testing data, and the ratio of mercury input in the coal to mercury output at the stack was from 0.84 to 1.08. 展开更多
关键词 mercury speciation mercury removal air pollution control device field testing
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Study of heavy metal speciation in branch sediments of Poyang Lake 被引量:11
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作者 LUO Mingbiao LI Jianqiang +1 位作者 CAO Weipeng WANG Maolan 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第2期161-166,共6页
This study concentrates on the environmental pollution level of sediments in the six branches of Poyang Lake, the biggest fresh water lake in China. This is the first systematic report on the speciation analysis of he... This study concentrates on the environmental pollution level of sediments in the six branches of Poyang Lake, the biggest fresh water lake in China. This is the first systematic report on the speciation analysis of heavy metals (Cu, Co, Cd, Pb, and Ni) in the six branches of the lake. A reported analytical procedure involving a five-step sequential extraction is used for the partition of particulating heavy metals. The sediment samples are analyzed using flame atomic absorption spectroscopy (FAAS). Experimental results obtained from five replicate samples of fluvial bottom surface sediments at the sampling points demonstrated that the relative standard deviation of the sequential extraction procedure was generally better than 10% (Cd except). The average extracted contents of the five elements, analyzed after all five steps, are found to be (mg/kg) for Cu: 26.89, Co: 16.25, Cd: 1.08, Pb: 37.98, and Ni: 20.46. The content of the exchangeable species was generally lower. Except Cu, the percentage of the species bond to organic matter was lower than 20%. The fractions containing the most metal for Cu, Co, and Ni were the residues (52.26%, 45.28%, and 74.82%, respectively). 展开更多
关键词 Poyang Lake speciation analysis heavy metal sequential extraction
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Speciation and fractionation of heavy metals in soil experimentally contaminated with Pb, Cd, Cu and Zn together and effects on soil negative surface charge 被引量:10
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作者 ZHOU Dong mei, HAO Xiu zhen, TU Cong, CHEN Huai man, SI You bin (Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China. ) 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2002年第4期439-444,共6页
Speciation and fractionation of heavy metals in soil subsamples experimentally loaded with Pb, Cd, Cu and Zn in orthogonal design was investigated by sequential extraction, and operationally defined as water soluble ... Speciation and fractionation of heavy metals in soil subsamples experimentally loaded with Pb, Cd, Cu and Zn in orthogonal design was investigated by sequential extraction, and operationally defined as water soluble and exchangeable(SE), weakly specific adsorbed(WSA), Fe and Mn oxides bound(OX) and organic bound(ORG). The results showed that fractions of heavy metals in the soil subsamples depended on their speciation. About 90% of Cd and 75% of Zn existed in soil subsamples in the SE fraction. Lead and Cu existed in soil subsamples as SE, WSA and OX fractions simultaneously, although SE was still the major fraction. Organic bound heavy metals were not clearly apparent in all the soil subsamples. The concentration of some heavy metal fractions in soil subsamples showed the good correlation with ionic impulsion of soil, especially for the SE fraction. Continuous saturation of soil subsamples with 0.20 mol/L NH 4Cl, which is the first step for determination of the negative surface charge of soil by the ion retention method, resulted in desorption of certain heavy metals from the soil. It was found that the percentage desorption of heavy metals from soil subsamples depended greatly on pH, the composition and original heavy metal content of the soil subsamples. However, most of the heavy metals in the soil subsamples were still be retained after multiple saturation. Compared with the parent soil, the negative surface charge of soil subsamples loaded with heavy metals did not show difference significantly from that of the parent one by statistical analysis. Heavy metals existed in the soil subsamples mainly as exchangeable and precipitated simultaneously. 展开更多
关键词 SOIL heavy metals speciation soil surface charge
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The role of arbuscular mycorrhiza on change of heavy metal speciation in rhizosphere of maize in wastewater irrigated agriculture soil 被引量:9
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作者 HUANGYi TAOShu CHENYou-jian 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第2期276-280,共5页
To understand the roles of mycorrhiza in metal speciation in the rhizosphere and the impact on increasing host plant tolerance against excessive heavy metals in soil, maize(Zea mays L.) inoculated with arbuscular myco... To understand the roles of mycorrhiza in metal speciation in the rhizosphere and the impact on increasing host plant tolerance against excessive heavy metals in soil, maize(Zea mays L.) inoculated with arbuscular mycorrhizal fungus(Glomus mosseae) was cultivated in heavy metal contaminated soil. Speciations of copper, zinc and lead in the soil were analyzed with the technique of sequential extraction. The results showed that,in comparison to the bolked soil, the exchangeable copper increased from 26% to 43% in non-infected and AM-infected rhizoshpere respectively; while other speciation (organic, carbonate and Fe-Mn oxide copper) remained constant and the organic bound zinc and lead also increased but the exchangeable zinc and lead were undetectable. The organic bound copper, zinc and lead were higher by 15%, 40% and 20%, respectively, in the rhizosphere of arbuscular mycorrhiza infected maize in comparison to the non-infected maize. The results might indicate that mycorrhiza could protect its host plants from the phytotoxicity of excessive copper, zinc and lead by changing the speciation from bio-available to the non-bio-available form. The fact that copper and zinc accumulation in the roots and shoots of mycorrhia infected plants were significantly lower than those in the non-infected plants might also suggest that mycorrhiza efficiently restricted excessive copper and zinc absorptions into the host plants. Compared to the non-infected seedlings, the lead content of infected seedlings was 60% higher in shoots. This might illustrate that mycorrhiza have a different mechanism for protecting its host from excessive lead phytotoxicity by chelating lead in the shoots. 展开更多
关键词 heavy metal speciation arbuscular mycorrhiza Glomus mosseae RHIZOSPHERE
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Chemodynamics of heavy metals in long-term contaminated soils:Metal speciation in soil solution 被引量:7
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作者 Kwon-Rae Kim Gary Owens 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第11期1532-1540,共9页
The concentration and speciation of heavy metals in soil solution isolated from long-term contaminated soils were investigated. The soil solution was extracted at 70% maximum water holding capacity (MWHC) after equi... The concentration and speciation of heavy metals in soil solution isolated from long-term contaminated soils were investigated. The soil solution was extracted at 70% maximum water holding capacity (MWHC) after equilibration for 24 h. The free metal concentrations (Cd^2+, Cu^2+, Pb^2+, and Zn^2+) in soil solution were determined using the Donnan membrane technique (DMT). Initially the DMT was validated using artificial solutions where the percentage of free metal ions were significantly correlated with the percentages predicted using MINTEQA2. However, there was a significant difference between the absolute free ion concentrations predicted by MINTEQA2 and the values determined by the DMT. This was due to the significant metal adsorption onto the cation exchange membrane used in the DMT with 20%, 28%, 44%, and 8% mass loss of the initial total concentration of Cd, Cu, Pb, and Zn in solution, respectively. This could result in a significant error in the determination of free metal ions when using DMT if no allowance for membrane cation adsorption was made. Relative to the total soluble metal concentrations the amounts of free Cd^2+ (3%-52%) and Zn^2+ (11%-72%) in soil solutions were generally higher than those of Cu^2+ (0.2%-30%) and Pb^2+ (0.6%-10%). Among the key soil solution properties, dissolved heavy metal concentrations were the most significant factor governing free metal ion concentrations. Soil solution pH showed only a weak relationship with free metal ion partitioning coefficients (Kp) and dissolved organic carbon did not show any significant influence on Kp. 展开更多
关键词 Donnan membrane technique free metal ion heavy metals partitioning coefficient SOLUBILITY speciation
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Heavy metals in surficial sediments of the central Bohai Sea:their distribution,speciation and sources 被引量:7
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作者 LIU Ming FAN Dejiang +2 位作者 LIAO Yongjie CHEN Bin YANG Zuosheng 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第9期98-110,共13页
The semi-enclosed Bohai Sea has received large amount of pollutants from surrounding rivers and sewage channels along the densely populated and industrializing Bohai coasts,as well as the offshore oil exploration in t... The semi-enclosed Bohai Sea has received large amount of pollutants from surrounding rivers and sewage channels along the densely populated and industrializing Bohai coasts,as well as the offshore oil exploration in the sea.The concentrations of heavy metals copper,cobalt,nickel,zinc,lead,chromium and cadmium in 25 surface sediment samples from the central Bohai Sea are obtained by ICP-MS analysis.The speciation of these heavy metals is extracted and their distribution,fractionation,pollution status and sources are presented.High concentrations of copper,cobalt,nickel,zinc and chromium are found in the sediments off the coastal area of the Bohai Bay and the central Bohai Sea mud,while high concentrations of cadmium and lead are found in the sediments in the whole study area.The residual fraction is the dominant form of copper,cobalt,nickel,zinc and chromium in the surface sediments,while cadmium and lead have large proportions in the nonresidual fractions.The ecological risk assessment shows that the sediments in the study area are unpolluted with respect to the heavy metals of cobalt,nickel and chromium and unpolluted to moderately polluted with respect to copper,zinc,cadmium and lead.Cobalt,nickel and chromium mainly have natural origin and their concentrations significantly vary with the composition of the sediments.The contents of copper,zinc,lead and especially cadmium in sediments are suggested to be influenced by pollutants of human activities.The heavy metals in the surface sediments at most sampling stations are mainly come from the Huanghe River; the heavy metals in the sediments in the northernmost part of the study area are significantly affected by the sediment from the Luanhe River; while in the Bohai Bay and the central region they were affected by the sediment from the Haihe River and aerosol deposition. 展开更多
关键词 heavy metal central Bohai Sea speciation environment quality source
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Phosphorus speciation in sediments of Lake Hongfeng, China 被引量:7
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作者 蒋翠红 胡继伟 +4 位作者 黄先飞 李存雄 邓家军 张杰 刘峰 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第1期53-62,共10页
This study was conducted to evaluate the distribution characteristics of phosphorus and its species in 14 sediments samples collected from Lake Hongfeng based on sequential extraction. Lake Hongfeng, a major drinking-... This study was conducted to evaluate the distribution characteristics of phosphorus and its species in 14 sediments samples collected from Lake Hongfeng based on sequential extraction. Lake Hongfeng, a major drinking-water source for Guiyang City in southwestern China, is one of the largest artificial reservoirs located in a typical karstic area of the Yunnan-Guizhou Plateau. The results of this study indicate that the average percentages of DP, Al-P, Fe-P, Ca-P and OP in the lake sediments were 0.52, 6.59, 6.09, 42.85 and 40.27, respectively. The concentrations of organic phosphorus (OP) were lower than those of inorganic phosphorus (IP), which consisted mainly of calcium-bound phosphorus (Ca-P). The high concentrations of Ca-P may temporarily control the release of phosphorus from the sediments because it is a relatively stable, inert, and non-bioavailable phosphorus fraction. However, a large number of phosphate solubilizing bacteria can transform insoluble phosphate into bioavailable forms. Moreover, the concentrations of total phosphorus (TP) in the lake sediments were high; thus, the potential for the release of phosphorus from the sediments to the water column and phosphorus bioavailability were still significant. Further statistical analyses of the results revealed significant correlations between phosphorus species in sediments from the lake with two extractable principal component species (PCs) and five selectable cluster levels allowing interpretation of possible origins of phosphorus loading and the release of phosphorus. Furthermore, available remediation measures were briefly assessed for the lake with consideration of its distinctive environmental features. 展开更多
关键词 EUTROPHICATION karstic environment lake sediments phosphorus speciation sequential extraction procedure
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Chemical speciation and mobility of heavy metals in municipal solid waste incinerator fly ash 被引量:8
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作者 LIUFeng LIUJian-guo +1 位作者 YUQian-feng NIEYong-feng 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第6期885-888,共4页
Chemical speciation is a significant factor that governs the toxicity and mobility of heavy metals in municipal solid waste incinerator fly ash. Sequential extraction procedure is applied to fractionate heavy metals(P... Chemical speciation is a significant factor that governs the toxicity and mobility of heavy metals in municipal solid waste incinerator fly ash. Sequential extraction procedure is applied to fractionate heavy metals(Pb, Zn, Cd, Cu, and Cr) into five defined groups: exchangeable, carbonate, Fe-Mn oxide, organic, and residual fractions. The mobility of heavy metals is also investigated with the aid of toxicity characteristic leaching procedure. In the fly ash sample, Pb is primarily presented in the carbonate(51%) and exchangeable(20%) fractions; Cd and Zn mainly exist as the exchangeable(83% and 49% respectively); Cu is mostly contained in the last three fractions(totally 87%); and Cr is mainly contained in the residual fraction(62%). Pb, Zn and Cd showed the high mobility in the investigation, thus might be of risk to the natural environment when municipal solid waste incinerator fly ash is landfilled or reutilized. 展开更多
关键词 municipal solid waste incinerator fly ash heavy metals chemical speciation MOBILITY
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Phosphorus speciation and distribution in surface sediments of the Yellow Sea and East China Sea and potential impacts on ecosystem 被引量:7
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作者 SONG Guodong LIU Sumei 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第4期84-91,共8页
For better understanding the phosphorus (P) cycle and its impacts on one of the most important fishing grounds and pressures on the marine ecosystem in the Yellow Sea (YS) and East China Sea (ECS), it is essenti... For better understanding the phosphorus (P) cycle and its impacts on one of the most important fishing grounds and pressures on the marine ecosystem in the Yellow Sea (YS) and East China Sea (ECS), it is essential to distinguish the contents of different P speciation in sediments and have the knowledge of its distribution and bioavailability. In this study, the modified SEDEX procedure was employed to quantify the different forms of P in sediments. The contents of phosphorus fractions in surface sediments were 0.20–0.89μmol/g for exchangeable-P (Exch-P), 0.37–2.86μmol/g for Fe-bound P (Fe-P), 0.61–3.07μmol/g for authigenic Ca-P (ACa-P), 6.39–13.73μmol/g for detrital-P (DAP) and 0.54–10.06μmol/g for organic P (OP). The distribution of Exch-P, Fe-P and OP seemed to be similar. The concentrations of Exch-P, Fe-P and OP were slightly higher in the Yellow Sea than that in the East China Sea, and low concentrations could be observed in the middle part of the ECS and southwest off Cheju Island. The distribution of ACa-P was different from those of Exch-P, Fe-P and OP. DAP was the major fraction of sedimentary P in the research region. The sum of Exch-P, Fe-P and OP may be thought to be potentially bioavailable P in the research region. The percentage of bioavailable P in TP ranged from 13%to 61%. Bioavailable P burial flux that appeared regional differences was affected by sedimentation rates, porosity and bioavailable P content, and the distribution of bioavailable P burial flux were almost the same as that of TP burial flux. 展开更多
关键词 phosphorus speciation burial flux SEDIMENT Yellow Sea East China Sea
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Al(III) speciation distribution and transformation in high concentration PACl solutions 被引量:6
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作者 HUANG Li TANG Hong-xiao +2 位作者 WANG Dong-sheng WANG Shui-feng DENG Zai-jun 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2006年第5期872-879,共8页
Effects of Al(Ⅲ) concentration and pH on the speciation of Al(Ⅲ) in polyaluminum chloride (PACl) solutions especially on the Al13 fraction were investigated. A series of PACl samples were prepared over the ran... Effects of Al(Ⅲ) concentration and pH on the speciation of Al(Ⅲ) in polyaluminum chloride (PACl) solutions especially on the Al13 fraction were investigated. A series of PACl samples were prepared over the range of Al(Ⅲ) concentration from 0.01 to 2.0 mol/L with the B (OH/Al ratio) value from 1.0 to 2.5 by forced hydrolysis of AICl3. The samples were characterized by ferron assay, pH and 27^Al NMR. It was shown that the Al(Ⅲ) concentration had a dramatic effect on the hydrolysis processes and the species distribution of PACl was in relate to the decrease of pH. The fraction of Al species, Alb (or Al13) decreased and Al0 increased with increase of total Al(Ⅲ) concentration. Under the condition of Al(Ⅲ) 2.0 reel/L, B = 2.5, the pH value was 2.73 and no Al13 could be detected. During diluting and aging, the species distribution evoIved. The Al13 could then be detected again and the amounts increased with time. If the diluted samples were concentrated by freeze dry at -35℃ or heating at 80℃, the pH value and Al13 content would decrease with the increased concentration. It demonstrated that the key factor for formation of Al13 in concentrated PACl was pH value. 展开更多
关键词 PACL AL13 B value pH speciation
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Environmental impact factors and mercury speciation in the sediment along Fujian and eastern Guangdong coasts 被引量:6
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作者 ZHANG Yuanbiao HUO Yunlong +3 位作者 LIU Xiyao KUANG Weiming YUAN Dongxing JI Weidong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2013年第2期76-80,共5页
Concentrations of total mercury (THg) and methyl mercury (MeHg) were determined for 32 surface sed- iments collected along the coastal line of Fujian Province and eastern Guangdong Province. The spatial distributi... Concentrations of total mercury (THg) and methyl mercury (MeHg) were determined for 32 surface sed- iments collected along the coastal line of Fujian Province and eastern Guangdong Province. The spatial distributions of THg and MeHg and their environmental impact factors were investigated. The average con- centrations of THg and MeHg in the sediments were 31.5 ng/g and 0.096 ng/g, respectively. Both sediment THg and MeHg concentrations showed relatively high value in the Minjiang Estuary and the coastal areas of Quanzhou and Putian. The concentrations overall decreased as the distance to the shoreline increased. The correlations among environmental impact factors and THg, MeHg were analyzed. The sediment THg concentration was highly correlated to the concentrations of organic matter, copper, total nitrogen (TN) and total phosphorus (TP), and significantly correlated to pH value of the bottom seawater and concentration of sediment sulfide. The sediment MeHg concentration was highly correlated to the concentrations of organic matter and copper, and significant correlated to the concentrations of sulfide, TN, TP and pH value of the bottom seawater. 展开更多
关键词 MERCURY methyl mercury coastal area SEDIMENT speciation
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Effects of As on As uptake, speciation, and nutrient uptake by winter wheat (Triticum aestivum L.) under hydroponic conditions 被引量:6
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作者 LIU Quanji HU Chengxiao TAN Qiling SUN Xuecheng SU Jingjun LIANG Yuexiang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第3期326-331,共6页
A hydroponic experiment was conducted to investigate the effects of arsenic (As) stress on growth, nutrition and As uptake, and speciation in shoots and roots of winter wheat (Triticum aestivum L.). Winter wheat h... A hydroponic experiment was conducted to investigate the effects of arsenic (As) stress on growth, nutrition and As uptake, and speciation in shoots and roots of winter wheat (Triticum aestivum L.). Winter wheat has high tolerance to As. Most As is accumulated in the roots, and an As concentration of 4,421 mg/kg was observed at a solution concentration of 20 mg/L As. Arsenic concentrations in roots were approximately 40-100 times greater than those in shoots. Arsenic in winter wheat roots and shoots occurred as both As^3+ and As^5+ species, although As^3+ was the main species in winter wheat tissues. Arsenic significantly decreased the biomass of winter wheat shoots and roots and affected absorption and transport of micro- and macro-elements in winter wheat tissue. Arsenic treatment significantly increased the concentrations of total Magnesium (Mg) and calcium (Ca) in shoots and enhanced the transport of Mg and Ca from roots to shoots but decreased potassium (K), nitrogen (N), and phosphorus (P) concentrations in both shoots and roots, particularly the concentration of P. Concentrations of iron, copper, and zinc in winter wheat shoots were negatively related to As rates, with correlation coefficients (R^2) of 0.93, 0.94, and 0.97, respectively. 展开更多
关键词 arsenic (As) winter wheat nutrients speciation
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