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Distribution,risk evaluation,and source analysis of the heavy metals in the sediment deposition of the lower Shichuanhe River,Shaanxi,China
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作者 Chenhui Hou Caixia Feng Shen Liu 《Acta Geochimica》 EI CAS CSCD 2023年第5期832-844,共13页
In this study, 30 sediment samples were collected from the lower reaches of the Shichuanhe River in Xi’an, Shaanxi Province, China, to test the distribution of heavy metal elements in this area and for an analysis of... In this study, 30 sediment samples were collected from the lower reaches of the Shichuanhe River in Xi’an, Shaanxi Province, China, to test the distribution of heavy metal elements in this area and for an analysis of the pollution levels of this area, hope to provide guidance on agricultural production activities in this region. The results show that the heavy metal elements in this area are mainly concentrated at the Qinghe River and Shichuanhe River confluences. Furthermore, the element contents are higher than that of the background levels of the continental crust(UCC) and close to the background levels of the soil from Shaanxi Province;the two most enriched elements are Cd and As, with contents of 0.79 and 22.7 mg·kg-1, respectively, and their contents are 3.8 and 1.72 times higher than that of the background values. Herein, the heavy metal pollution assessment methods applied indicated that Cd and As are the two most abundant pollutant elements in the area’s soils. As has a peak geo-accumulation index value of 3, and the pollution level is high, while Cd exhibits high potential ecological risks due to its high toxicity(potential risk index of 143) and an active fraction of more than 64%.In addition, a principal component analysis and hierarchical cluster analysis study showed that there are two sources of the heavy metals in this area. The Zn, As, Ni, Cu, Pb,and Cr are mainly from natural sources, and the Cd likely comes from a discharge of untreated agricultural wastewater in the region. The Cd which poses a high potential risk and mainly results from human activities, needs to be further monitored. 展开更多
关键词 distribution Risk evaluation Source analysis heavy metals SEDIMENT Ecological risk
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Tissue distribution of cadmium and its effect on reproduction in Spodoptera exigua
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作者 Honghua Su Menglu Wu +3 位作者 Yong Yang Yan Deng Yizhong Yang Qingming Sun 《Journal of Integrative Agriculture》 SCIE CSCD 2024年第1期195-204,共10页
Vegetable fields are often contaminated by heavy metals,and Spodoptera exigua is a major vegetable pest which is stressed by heavy metals mainly by feeding.In this study,cadmium accumulation in the tissues of S.exigua... Vegetable fields are often contaminated by heavy metals,and Spodoptera exigua is a major vegetable pest which is stressed by heavy metals mainly by feeding.In this study,cadmium accumulation in the tissues of S.exigua exposed to cadmium and its effects on the growth and development of the parents and the offspring were investigated.Under the stress of different concentrations of cadmium(0.2,3.2,and 51.2 mg kg^(-1)),the cadmium content in each tissue of S.exigua increased in a dose-dependent manner.At the larval stage,the highest cadmium accumulation was found in midgut in all three cadmium treatments,but at the adult stage,the highest cadmium content was found in fat body.In addition,the cadmium content in ovaries was much higher than in testes.When F1S.exigua was stressed by cadmium and the F_(2)generation was not fed a cadmium-containing diet,the larval survival,pupation rate,emergence rate and fecundity of the F_(2)generation were significantly reduced in the 51.2 mg kg^(-1)treatment compared to the corresponding F1generation.Even in the F_(2)generation of the 3.2 mg kg^(-1)treatment,the fecundity was significantly lower than in the parental generation.The fecundity of the only-female stressed treatment was significantly lower than that of the only-male stressed treatment at the 3.2 and 51.2 mg kg^(-1)cadmium exposure levels.When only mothers were stressed at the larval stage,the fecundity of the F_(2)generation was significantly lower than that of the F1generation in the 51.2 mg kg^(-1)treatment,and it was also significantly lower than in the 3.2 and 0.2 mg kg^(-1)treatments.The results of our study can provide useful information for forecasting the population increase trends under different heavy metal stress conditions and for the reliable environmental risk assessment of heavy metal pollution. 展开更多
关键词 heavy metal pollution CADMIUM Spodoptera exigua tissue distribution REPRODUCTION
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GIS Mapping, Biomonitoring and Distribution of Heavy Metal Concentrations Using Neem (Azadirachta indica) Bark in Makurdi Town, Benue State, Nigeria
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作者 Ada Florence Ogli Mohammed Ahmed +2 位作者 Adams Udoji Itodo Raymond Ahulle Wuana Rufus Sha’Ato 《Journal of Geoscience and Environment Protection》 2023年第7期213-226,共14页
The present work determined the concentration and spatial distribution of heavy metals (As, Hg, Cr, Cd and Pb) in soil samples from Makurdi and its environs using geographic information system (GIS). The specific obje... The present work determined the concentration and spatial distribution of heavy metals (As, Hg, Cr, Cd and Pb) in soil samples from Makurdi and its environs using geographic information system (GIS). The specific objective is to produce the spatial distribution maps showing the spatial distribution of toxic heavy metals in the study area. Inverse Distance Weighting (IDW), a GIS technique was used to produce dotted maps showing the spatial distribution of heavy metals in neem bark for better visualization of contamination zones and non-contamination zones. The map reveals few hotspot areas showing areas of high concentrations of the heavy metals investigated which were identified in red colours, the following concentration ranges were obtained;As (4.71 - 6.43 mg/kg), Cd (13.9 - 16.84 mg/kg), Cr (46.3 - 60.84 mg/kg), Hg (3.70 - 5.05 mg/kg) and Pb (24.02 - 31.34 mg/kg). These hotspot areas were found close to business outlets, fuel filling and service stations, farm sites where the application of fertilizers and pesticides were persistent coupled with heavy traffic of vehicles and other machinery which was associated with As, Hg, Cd, Pb and Cr been released into the environment thus, suggesting anthropogenic activities controlling the concentration of these heavy metals in the study areas. The cumulative effect of these heavy metals into the barks of neem could pose as danger, because this plant is used as herbs in folk medicine. 展开更多
关键词 heavy Metal Contamination Spatial distribution Inverse Distance Weighting Folk Medicine Makurdi
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Fraction distribution and risk assessment of heavy metals in sediments of Moshui Lake 被引量:46
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作者 LIU Honglei LI Liqing YIN Chengqing SHAN Baoqing 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第4期390-397,共8页
To examine the status and risk of heavy metal pollution in urban lakes, in China, the distribution of several heavy metals (e.g., Cr, Cu, Ni, Pb, Zn) in the sediment of Moshui Lake, Hangyang District, Wuhan City, wa... To examine the status and risk of heavy metal pollution in urban lakes, in China, the distribution of several heavy metals (e.g., Cr, Cu, Ni, Pb, Zn) in the sediment of Moshui Lake, Hangyang District, Wuhan City, was characterized. The process of rapid urbanization and industrialization of the district was also studied to find out its relationship with the metal accumulation profile in the sediment. It was found that the total concentration of heavy metals in the sediment was higher than the severe effect level (SEL), at all sampling sites, except those in the riparian zone. The Cr and Cu maximum concentrations were 1,780 and 1,250 mg/kg, approximately 16 and 11 times as much as the SEL values, and they appeared as deep as 32 cm in one sample. The carbonate and exchangeable fractions of Zn were more than 50% of the total Zn content, resulting in very high risk according to the Risk Assessment Code (RAC). For Cu and Ni, a medium RAC value was found for carbonate and exchangeable fractions of 11%-20%. As sensitive indicators of contaminants in aquatic systems, heavy metals in the sediment reflect the outcome of regional urbanization, industrialization, and environmental management. With rapid urbanization, sedimentary Pb and Zn concentrations increased. The experimental results showed that high sedimentary heavy metal concentrations had resulted from rapid urbanization and industrialization, which would absolutely lead to substantial aquatic environmental decline in urban lakes. 展开更多
关键词 distribution heavy metal risk sediment URBANIZATION
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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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Distribution and partitioning of heavy metals in large anthropogenically impacted river, the Pearl River, China 被引量:6
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作者 Silan Liu Zhongwei Wang +7 位作者 Yuanyuan Zhang Yulong Liu Wei Yuan Ting Zhang Yujie Liu Ping Li Li He Jiubin Chen 《Acta Geochimica》 EI CAS CSCD 2019年第2期216-231,共16页
In order to evaluate the distribution and partitioning characteristics of heavy metals in the large anthropogenically impacted Pearl River Basin, the contents of ‘‘anthropophile'' elements(Cr, Ni, Cu, Zn, Cd... In order to evaluate the distribution and partitioning characteristics of heavy metals in the large anthropogenically impacted Pearl River Basin, the contents of ‘‘anthropophile'' elements(Cr, Ni, Cu, Zn, Cd and Pb,which are clearly influenced by human activities) were determined, and their partitioning coefficients(Kd) between water and sediments and enrichment factors(EF) were calculated for samples collected at different locations along the Pearl River main stream. The modified BCR sequential extraction procedure(proposed by the European Community Bureau of Reference in 1993), which involves the successive extraction of metals in a decreasing order of reactivity, was applied. Sediment samples from the upper,middle, and lower reaches were included in this study. The results showed that the content of most metals in water and sediment samples gradually increases from upstream to downstream, suggesting a possible input from human activities as shown by their increasing high EF, ranged from 1.4 to 3.9 for Cu, from 1.4 to 6.7 for Zn, from 2.5 to59.1 for Cd, and from 1.7 to 8.9 for Pb, respectively. Thehigher partition coefficients(Kd) for Cr, Zn, and Pb(10~5–10~6) indicated that they were mainly transported in solid phase, while parts of Ni, Cu, and Cd were transported in dissolved phase as they display relatively lower Kdin the range of 10~4–10~5. According to the results of the BCR leaching, the percentage of non-residual fraction of heavy metals in the sediments showed a decreasing order of Cd [ Pb [ Zn [ Cu [ Ni [ Cr, implying that Cd and Pb were more active and bioavailable compared to the other four metals, and thus would be potentially more harmful to the watershed ecosystem. 展开更多
关键词 PEARL RIVER Water and SEDIMENT heavy metals Partitioning distribution
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Distribution and their pollution assessment of heavy metals in the sediments of the Yalu River Estuary and its adjacent coastal waters 被引量:4
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作者 GAO Jianhua LI Jun +5 位作者 Wang Harry V WANG Yaping WANG Zhenyan BAI Fenglong GAO Shu CHENG Yan 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2009年第6期12-23,共12页
The present paper deals with the distribution patterns of heavy metals and the associated influenc- ing factors in the Yalu River Estuary and its adjacent coastal waters. Based upon the analysis of the surficial and c... The present paper deals with the distribution patterns of heavy metals and the associated influenc- ing factors in the Yalu River Estuary and its adjacent coastal waters. Based upon the analysis of the surficial and core sediments measurements, the pollution of heavy metal and potentiM ecological risk were evaluated. The burial flux and contents of heavy metals (except for copper) have been continuously increasing since the 1920s. Therefore, the gross potential ecological risk for the sedi- ments was high or very high, and the study area was endangered by heavy metals contamination. Heavy metals originated mainly from upstream pollutant input, correlation analysis showed that chromium, nickel, zinc~ cadmium, lead, arsenic, and mercury in the sediments of the middle and west channels as well as the sea area of the western Yalu River Estuary concentrations were most probably derived from similar sources. In contrast, the metal of copper most probably originated from sources different from the other metals. Preliminary studies indicate that copper contamina- tion was most likely the result of emission from mining activities situated at the upstream of the river. The contents of heavy metals in the sediments of estuarine turbidity maximum zone of Yalu River were larger than those of any other areas in the middle channel. With large portion of fine sediments, weaker hydrodynamics, and richer sources of heavy metals, the sediments of the west channel, were even more enriched with heavy metals than those of the middle channel. 展开更多
关键词 heavy metals SEDIMENT pollution distribution ACCUMULATION Yalu River
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Horizontal distribution and levels of heavy metals in the biggest snowstorm in a century in Shenyang,China 被引量:3
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作者 AN Jing ZHOU Qixing +1 位作者 LIU Weitao REN Liping 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第7期846-851,共6页
The horizontal distribution and levels of heavy metals in the biggest snowstorm in Shenyang since 1904 were investigated by analyzing 4 metals (As,Cd,Pb,and Cu) in a series of ultraclean samples collected from 17 site... The horizontal distribution and levels of heavy metals in the biggest snowstorm in Shenyang since 1904 were investigated by analyzing 4 metals (As,Cd,Pb,and Cu) in a series of ultraclean samples collected from 17 sites distributed in different regions of the Shenyang area,China.The results showed that the concentrations of all the 4 heavy metals in snow from the industrial regions were high,up to 7.3 (As),2.2 (Cd),850.0 (Pb),and 0.197-20.2 (Cu)μg/kg,respectively.In the suburb,in contrast,their concentration... 展开更多
关键词 heavy metal distribution pollution level SNOWSTORM extreme climate
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Distribution and Migration of Heavy Metals in Undisturbed Forest Soils:A High Resolution Sampling Method 被引量:14
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作者 RUAN Xin-Ling ZHANG Gan-Lin +1 位作者 NI Liu-Jian HE Yue 《Pedosphere》 SCIE CAS CSCD 2008年第3期386-393,共8页
The vertical distribution and migration of Cu,Zn,Pb,and Cd in two forest soil profiles near an industrial emission source were investigated using a high resolution sampling method together with reference element Ti.On... The vertical distribution and migration of Cu,Zn,Pb,and Cd in two forest soil profiles near an industrial emission source were investigated using a high resolution sampling method together with reference element Ti.One-meter soil profile was sectioned horizontally at 2 cm intervals in the first 40 cm,5 cm intervals in the next 40 cm,and 10 cm intervals in the last 20 cm.The migration distance and rate of heavy metals in the soil profiles were calculated according to their relative concentrations in the profiles,as calibrated by the reference element Ti.The enrichment of heavy metals appeared in the uppermost layer of the forest soil,and the soil heavy metal concentrations decreased down the profile until reaching their background values.The calculated average migration rates of Cd,Cu,Pb,and Zn were 0.70,0.33,0.37,and 0.76 cm year-1,respectively,which were comparable to other methods.A simulation model was proposed,which could well describe the distribution of Cu,Zn,Pb,and Cd in natural forest soils. 展开更多
关键词 迁移速度 溶解能力 重金属 森林 土壤学
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Distribution of heavy-metals in the Grand Canal(Hangzhou section)and its contributing factors 被引量:1
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作者 Weng Huanxin, Zhang Dengrong Department of Earth Sciences, Zhejiang University, Hangzhou 310027, China Charlie Y.Xu Department of Geological Sciences, University of Illinois at Chicago. U.S.A. 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1997年第3期12-24,共13页
The Grand Canal (Hangzhou section), People's Republic of China, has been highly contaminated by heavy metals from both industrial and municipal sources since 1950s. This study investigated the distribution of heav... The Grand Canal (Hangzhou section), People's Republic of China, has been highly contaminated by heavy metals from both industrial and municipal sources since 1950s. This study investigated the distribution of heavy metals including As, Cr, Cd, Cu, Ni, Pb, and Zn. The results showed that these metals are largely accumulated in the top 0 3 meter layer of the river sediment.Despite the contamination, heavy metal concentrations in solution are increased in some locations only. The only exception is Zn whose concentrations are extremely high both in solution and in the top layer sediment. The top layer sediment appears to have reached almost its sorption capacity with respect to aqueous Zn. The extent of contamination is in the sequence of Zn>Cu>Pb>As>Cd. It is speculated that Cu distribution has been significantly affected by its binding to organic matter in the top layer sediment. Based on Pb distribution in both water and sediment, it is suggested that Pb transport in the canal is associated with colloids or particles suspended in water. The study showed that the top layer sediment in the Grand Canal serves as a sink to anthropogenic contaminants consisting of heavy metals as well as organic compounds. 展开更多
关键词 heavy metal distribution contributing factor the Grand Canal (Hangzhou section).
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Seasonal and spatial distribution of heavy metals in the Selenga River Delta 被引量:1
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作者 Z.I. KHAZHEEVA A.K. TULOKHONOV +1 位作者 YAO Rui HU Weiping 《Journal of Geographical Sciences》 SCIE CSCD 2008年第3期319-327,共9页
In order to estimate the present-day pollution levels in the ecosystem of the Selenga River Delta and to monitor the changes caused by the discharge of household refuse and industrial wastes,as well as the functioning... In order to estimate the present-day pollution levels in the ecosystem of the Selenga River Delta and to monitor the changes caused by the discharge of household refuse and industrial wastes,as well as the functioning of the agricultural and stock farming,a comprehensive study of the water and bottom sediments in the main branches of the Selenga River Delta was carried out.This study has determined the concentrations of heavy metals in river water and bottom sediments in its delta. 展开更多
关键词 heavy metal seasonal and spatial distribution Selenga River Delta
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Heavy Metals in Urban Soils of Xuzhou, China: Spatial Distribution and Correlation to Specific Magnetic Susceptibility 被引量:1
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作者 Xuesong Wang 《International Journal of Geosciences》 2013年第2期309-316,共8页
The investigation of the anthropogenic contamination by heavy metals of soils is very important for environmental planning and monitoring in urban areas. In the present study, surface soils (0-20 cm) samples from 167 ... The investigation of the anthropogenic contamination by heavy metals of soils is very important for environmental planning and monitoring in urban areas. In the present study, surface soils (0-20 cm) samples from 167 sampling sites in Xuzhou (China) were collected in 2010 and analyzed for heavy metals including Zn, Pb, Fe, Mn, Cu, Cd, Sr, Ba Cr, Ni and Mo via inductively coupled plasma/mass spectrometry (ICP-MS). Compared with their levels in natural soils of China, these metals investigated exhibited a slight build-up in Xuzhou topsoils. The multivariate statistical analyses including factor analysis (FA) and cluster analysis (CA) were performed. The obtained results enabled the identification of two main groups of metals, discriminating Ni, Mo and Cr from Zn, Pb, Fe, Mn, Cu, Cd, Sr and Ba. Signifcant associations between Pb, Zn, Fe and specific magnetic susceptibility (c) indicated that specific susceptibility can serve as proxies for these metals levels in Xuzhou urban soils. 展开更多
关键词 heavy metals Spatial distribution SPECIFIC Magnetic SUSCEPTIBILITY Urban SOILS XUZHOU
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Spatial Distribution and Risk Assessment of Heavy Metals in Paddy Soils of Yongshuyu Irrigation Area from Songhua River Basin,Northeast China 被引量:9
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作者 CUI Zhengwu WANG Yang +3 位作者 ZHAO Na YU Rui XU Guanghui YU Yong 《Chinese Geographical Science》 SCIE CSCD 2018年第5期797-809,共13页
There is an increasing concern for potentially hazardous metals pollution, which can threaten crops production and human health. In this study, the spatial distribution and environmental risks of eight heavy metals in... There is an increasing concern for potentially hazardous metals pollution, which can threaten crops production and human health. In this study, the spatial distribution and environmental risks of eight heavy metals in surface soil samples collected from the paddy fields in Yongshuyu irrigation area, Northeast China were investigated. The mean concentrations of Pb, Cr, Cu, Ni, Zn, Cd, Hg and As were 34.6 ± 4.67, 82.8 ± 9.51, 17.3 ± 4.09, 21.2 ± 12.0, 88.6 ± 17.9, 0.18 ± 0.15, 0.22 ± 0.07 and 8.77 ± 2.47 mg/kg, respectively, which were slightly higher than their corresponding background values of Jilin Province, indicating enrichment of these metals in the paddy soils, especially for Ni, Cd and Hg. The spatial distribution of heavy metals was closely correlated with local anthropogenic activities, such as agricultural production, mining and transportation. The hot-spot areas of As and Cd were mainly concentrated in the up-midstream where were associated with agricultural activities. Cr and Cu showed similar spatial distributions with hot-spot areas distributed the whole irrigation area uniformly. Ni was mainly distributed in the downstream where Ni quarries concentrated, while the spatial distribution patterns of Hg was mainly located in the upstream and downstream where the soil was significantly influenced by irrigation and coal mining emission. The spatial distributions of Pb and Zn were mainly concentrated along the highway side. The pollution levels of Yongshuyu irrigation area were estimated through index of geo-accumulation(Igeo), Nemerow integrated pollution index(NIPI) and potential ecological risk index(PERI). The results showed that Cd and Hg were the main pollutants in the study area. Health risk assessment results indicated that children were in higher non-carcinogenic and carcinogenic risks than adults with the carcinogenic metal of As. Ingestion was the main exposure pathway to non-carcinogenic and carcinogenic risk for both adults and children. Principal component analysis(PCA) indicated that Cr and Cu were mainly from parent materials, while Cd and As were mainly affected by agricultural activities. Pb and Zn were controlled by traffic activities, and the accumulations of Ni and Hg were associated with mining activities. This study would be valuable for preventing heavy metals inputs and safety in rice production of the Songhua river basin. 展开更多
关键词 健康风险评价 空间分布 土壤样品 分发模式 重金属 灌溉区 中国 东北
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Spatial distribution,sources and ecological risk assessment of heavy metals in Shenjia River watershed of the Three Gorges Reservoir Area 被引量:10
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作者 WANG Yong-yan WEN An-bang +2 位作者 GUO Jin SHI Zhong-lin YAN Dong-chun 《Journal of Mountain Science》 SCIE CSCD 2017年第2期325-335,共11页
Surface soil/sediment samples were collected from the Water-Level Fluctuation Zone(WLFZ), cultivated land and forest land at 50 different grid points from Shenjia watershed, the Three Gorges Reservoir area in August 2... Surface soil/sediment samples were collected from the Water-Level Fluctuation Zone(WLFZ), cultivated land and forest land at 50 different grid points from Shenjia watershed, the Three Gorges Reservoir area in August 2013. The spatial distribution, sources and ecological risk assessment for Arsenic(As), Cadmium(Cd),Chromium(Cr), Copper(Cu), Nickel(Ni), Lead(Pb)and Zinc(Zn) were analyzed in this study. The results showed all tested metals had similar distribution patterns except Ni and Cr, with areas of high concentrations distributed in the southwest(WLFZ and watershed outlet) of the study area. Ni and Cr,which were highly positively correlated and present in high concentrations, were primarily distributed in the south and middle zones of the study area. Lower concentration areas of all metals were uniformly distributed west of the high-elevation zones and forest land. Factor analysis(FA) and factor analysismultiple linear regression(FA-MLR) showed that the major sources of Cd were fertilizer and traffic sources,which together accounted for 87% of Cd. As, Zn and Cu levels were primarily supplied by industrial and domestic sources, accounting for 76% of As, 75% of Cu and 67% of Zn. Surface soils/sediments of the study watershed contaminated by Cd represent a high ecological risk, whereas other metals represent low ecological risks. The potential ecological risk index(PERI) analysis indicated that it had a low(widerange) ecological risk and a moderate(small-range)ecological risk primarily distributed in the outlet of the study watershed. Fertilizers and traffic are the primary sources of Cd pollution, which should be more closely controlled for the purposes of water quality and ecological conservation. 展开更多
关键词 生态风险评价 重金属污染 空间分布 三峡库区 河流域 土壤/沉积物 镉(Cd) 低浓度区
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Levels and spatial distribution of heavy metals in urban dust in China 被引量:2
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作者 Xiaoyan Li 《Chinese Journal Of Geochemistry》 EI CAS CSCD 2015年第4期498-506,共9页
Many studies have been conducted on heavy metal concentrations in urban outdoor dust in China,showing that differences exist in the metal concentrations of different cities. However, no report has studied the distribu... Many studies have been conducted on heavy metal concentrations in urban outdoor dust in China,showing that differences exist in the metal concentrations of different cities. However, no report has studied the distribution of heavy metals across Chinese cities. This work presents the spatial distribution of heavy metals in urban outdoor dust in Chinese cities and discusses the causes for the differences in heavy metal levels across cities by analyzing and summarizing data for 20 provincial capitals from the published scientific literature. The results show that the geometric mean values of Ni and Cr in urban dust of China are lower than or comparable to crustal levels, whereas levels of Cd, Cu, Pb, and Zn are significantly greater than crustal levels. The spatial distributions of Cu, Pb, and Zn in urban dust all exhibit a pattern in which heavy metal levels are greater in cities located in the south of China than in the north. Commercial areas and residential-education areas accumulate more Cd in their dust than industrial areas and traffic areas, and industrial areas and residential-education areas accumulate more Pb than commercial areas and traffic areas. The Zn level in dust from industrial areas is significantly greater than in other areas, and Cu exhibits no significant difference between different functional areas. A positive correlation exists between Cd and Zn in urban dust and population density. Urban dust Pb in Chinese cities is lower than the world average as calculated using data for thirteen cities in different countries. Cd, Cu, and Zn levels in China are close to world averages. 展开更多
关键词 空间分布特征 重金属含量 城市灰尘 中国城市 几何平均值 空间分布格局 教育领域 交通领域
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Distribution and accumulation of heavy metals in Avicennia marina community in Shenzhen,China 被引量:1
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《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1997年第4期90-97,共8页
DistributionandaccumulationofheavymetalsinAvicenniamarinacommunityinShenzhen,ChinaLinPeng,ZhengWenjian,LiZhe... DistributionandaccumulationofheavymetalsinAvicenniamarinacommunityinShenzhen,ChinaLinPeng,ZhengWenjian,LiZhenjiDepartmentofBi... 展开更多
关键词 distribution and accumulation of heavy metals in Avicennia marina community in Shenzhen China
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Distribution,fractionation,and contamination assessment of heavy metals in offshore surface sediments from western Xiamen Bay,China 被引量:2
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作者 Qiuli Yang Gongren Hu +2 位作者 Ruilian Yu Haixing He Chengqi Lin 《Acta Geochimica》 EI CAS CSCD 2016年第4期355-367,共13页
Surface sediment samples were collected at 21 offshore sites in western Xiamen Bay, Southeast China.Total concentrations of Li, V, Cr, Co, Ni, Cu, Zn, Sr, Mn,Pb, Ba, Fe, and Ti were determined by inductively coupled p... Surface sediment samples were collected at 21 offshore sites in western Xiamen Bay, Southeast China.Total concentrations of Li, V, Cr, Co, Ni, Cu, Zn, Sr, Mn,Pb, Ba, Fe, and Ti were determined by inductively coupled plasma-optical emission spectrometry; Hg was determined by atomic fluorescence spectrometry. A modified BCR sequential extraction procedure was used to extract fractions of the above elements. Concentrations of Pb, Cr, and Hg at most sites met the primary standard criteria of Marine Sediment Quality except site S12 for Pb and S7 for Cr, while concentrations of Zn at 17 sites and Cu at seven sites exceeded the criteria. The mean concentration of Hg was three times higher than the background, with a possible source being the Jiulong River. Fe, Ti, Ba, Co, V, and Li dominated the residual phase, mainly from terrestrial input.Ni, Cr, Pb, and Hg in the non-residual phase varied largely between sites. Sr, Mn, Cu, and Zn were mainly in the nonresidual fraction. Most sites showed considerable ecological risk; exceptions were site S7(very high) and sites S10,S11, and S14(moderate). Cu showed moderate-to-high pollution and Pb exhibited no-to-low pollution, while other metals had a non-pollution status according to their ratios of secondary phase to primary phase(RSP). Results of two assessment methods showed moderate pollution and a veryhigh ecological risk for Cu, Zn, Ni, and Cr at site S7, which might be due to the local sewage treatment plant. 展开更多
关键词 中国东南部 污染评价 重金属 厦门湾 表面沉积物 电感耦合等离子体发射光谱法 原子荧光光谱法 连续提取法
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Content Analysis of Baicalin and Heavy Metals in Scutellaria baicalensis Georgi Cultivated in Jizhou District 被引量:2
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作者 Chenxi WANG Yi PEI +5 位作者 Ming YANG Wen XU Huiying JIAO Yaqi QIAO Jiangli NIE Ya SU 《Asian Agricultural Research》 2018年第10期93-96,101,共5页
This study aimed to explore an analysis method for baicalin in Scutellaria baicalensis Georgi and make a reference for the analysis of the medicinal value of S. baicalensis cultivated in Jizhou District. The content o... This study aimed to explore an analysis method for baicalin in Scutellaria baicalensis Georgi and make a reference for the analysis of the medicinal value of S. baicalensis cultivated in Jizhou District. The content of baicalin in S. baicalensis cultivated in Jizhou District was determined using high-performance liquid chromatography( HPLC) to judge whether it met the requirements of Chinese Pharmacopoeia; and according to the requirements of the Chinese Pharmacopoeia of 2015 edition,the contents of heavy metals were determined by ICP-MS. The results showed that the contents of baicalin,Cr,Cu,As,Cd and Pb in S. baicalensis planted in Jizhou District were 14. 625 05%,11. 360,12. 830,0. 062 315,0. 025 715 and 0. 176 65 μg/g,respectively. The content of baicalin in S. baicalensis planted in Jizhou District was much higher than the standard( ≥ 9. 0%) of Chinese Pharmacopoeia of 2015 edition,and the contents of heavy metals were also below the limit( ≤20/1000 000) required by Chinese Pharmacopoeia of 2015 edition. 展开更多
关键词 高效液相色谱法 黄芩 种植业 发展现状
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Analysis of Spatial Distribution Characteristics of Heavy Metals in Cultivated Land of Nehe City
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作者 Du Guo-ming Yuan Rui +1 位作者 Zhao Jing-bo Luo Yin-song 《Journal of Northeast Agricultural University(English Edition)》 CAS 2017年第2期14-22,共9页
This study aimed at gaining the cultivated land quality and the situation of soil pollution, taking Nehe City in Heilongjiang Province as an example, used ordinary Kriging interpolation of geostatistics, investigated ... This study aimed at gaining the cultivated land quality and the situation of soil pollution, taking Nehe City in Heilongjiang Province as an example, used ordinary Kriging interpolation of geostatistics, investigated the content and spatial distribution of eight kinds of heavy metal elements(namely Cd, Cr, Pb, Cu, Zn, Ni, Hg and As) in farming land soil, then analyzed the distinction and potential source of these heavy metal elements. The result showed that(1) all these elements had a certain amount of accumulation compared with those in the background of Heilongjiang Province, among which the accumulated levels of Cu and As were the highest.(2) Through statistic analyses, it showed that the spatial autocorrelation degrees of these four elements(namely Cd, Cr, Cu and Zn) were higher.(3) The pollution of Cd and Cu was relatively severe.(4) The spatial distribution features of these eight kinds of heavy metal elements were different, and the soil parent material and the human activity played double roles in the content distribution of heavy metal elements in farming land soil. 展开更多
关键词 heavy metal cultivated soil spatial distribution K_riging interpolation
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Statistical characteristics of heavy metals content in groundwater and their interrelationships in a certain antimony mine area
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作者 YU Kai-ning LI Jian +3 位作者 LI Hui CHEN Kang LV Bing-xu ZHAO Long-hui 《Journal of Groundwater Science and Engineering》 2016年第4期284-292,共9页
In recent years, most of domestic and foreign researches about heavy metal pollutions of metal mine mainly focus on water, soil and plants on the surface. There is lack of researches about heavy metal pollution in gro... In recent years, most of domestic and foreign researches about heavy metal pollutions of metal mine mainly focus on water, soil and plants on the surface. There is lack of researches about heavy metal pollution in groundwater of metal mine. In this research, a certain antimony mine area is selected as a typical study area. Also, the study about statistical characteristics of heavy metals in groundwater has been carried out. Furthermore, the interrelationships have been preliminarily discussed through related analysis, such as relevant analysis, cluster analysis and principle component analysis. The results show that: the excessive elements in groundwater of study area are Sb, As, Pb, Se, and Ni. The average mass concentration of Sb, As, and Pb is higher than that of drinking water standards(GB5749-2006). The concentration of most heavy metals in dry season is lower than or equal to that in wet season for groundwater. Zn is the only metal in groundwater showing a different pattern, the concentration of which in dry season is higher than that in wet season. Under the impacts of stratum leaching and absorption effect, the concentration of heavy metals(except Pb and Ba) in groundwater are lower than or equal to that in surface water. As and Se, the two heavy metals have a significant positive correlation, which shows the two elements might have gone through similar environmental geochemical effect. Also, the connection among Zn, Hg, Pb, and Mn is not obvious; therefore, the sources of those elements are quite different. In addition, the elements of Se and As have obvious positive interrelationship with elements of CO_3^(2-) and F^-. Also, the Pb has significant positive correlation with PO_4^(3-), H_2SiO_3 and oxygen consumption. The results of cluster analysis show that 9 different heavy metals in the study area can be divided into 3 categories: Zn, Cd, Mn, Hg, Cu, and Cr belong to the first category, Se and As belong to the second one, and the last category is Pb. Also, the principle component analysis divides 6 heavy metals(Zn, As, Hg, Pb, Mn, and Se) into 4 different principle components, which can be utilized to assess heavy metals pollution situations in groundwater. The reliability of this method is higher than 91%. Moreover, the research provides theory basis and models for establishing evaluation index system and exploring the evaluation method of heavy mental pollution in groundwater. 展开更多
关键词 GROUNDWATER heavy metals content Statistical characteristics INTERRELATIONSHIPS Antimony mine
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