Phytoremediation of Nephrolepis auriculata （L.） for arsenic, mercury, lead and cadmium in the multiple contaminated softs

In recent years, the concentrations of heavy metals in Chinese herb of Ligusticum chuanxong Hort are overranging the standard of national port of green herbs in GAP bases of Dujiangyan City, Sichuan Province. The aim of the research is to disclose the remediation behavior ofNephrolepis auriculata （L.）, a novel pteridophyta found in our research with abundant arsenic, mercury, lead and cadmium from soils. The concentrations of arsenic, mercury, lead and cadmium in the series samples corresponding to roots, stems, leaves ofNephrolepis auriculata （L.） which had been trained in lab with a series of potted incubation experiments through the orthogonal test, were analyzed. Based on the results, methods of the range analysis and variance analysis were used, and it is demonstrated that （1） Nephrolepis auriculata （L.） has a function to beneficiate heavy metals of arsenic and lead, and can well concentrate cadmium and mercury from soils. The distributive behaviors of arsenic, mercury, lead and cadmium in N. sauriculata （L.） follow the order： roots〉leaves〉corms〉stems, stems〉leaves〉roots〉corms, roots〉stems 〉corms〉leaves, stems〉leaves〉roots〉corms; the correlations of the concentrations for arsenic, lead, cadmium and mercury in different tisses of Nephrolepis auriculata （L.） and soils were carried out. Then, the effects of pH value, contents of EDTA and humic acid in soils to arsenic and mercury accumulated by Nephrolepis auriculata （L.） were further studied.     

Mercury concentrations in a contaminated river system in Kazakhstan and biomonitoring of the local population

The River Nura in central Kazakhstan has been heavily contaminated by mercury （Hg） from an acetaldehyde plant located in the industrial city of Temirtau. The plant released Hg-containing wastewater into the river from the 1950s until the mid 1990s and strongly contaminated the bed sediments up to 25 km downstream. In addition, a local power station released an estimated 6 million tonnes of fly-ash into the water which has adsorbed much of the Hg and has become mixed with the natural sediments. River water,fish and agricultural land in the floodplain are also contaminated by Hg. Humans are exposed to Hg primarily via the consumption of contaminated fish from the river. A survey was undertaken in June/July 2005 to investigate Hg concentrations in river water, drinking water, sediments and fish. To estimate the risk posed to the local population, approximately 300 hair samples were collected from people living in villages near the most contaminated section of the river, at a distance of between 5 and 30 km downstream of the acetaldehyde plant, and their dietary habits were recorded. Mercury concentrations in river water ranged from 2-3 ng/L upstream of the source of the pollution to 348 ng/L downstream of the factory outfall pipe. Some drinking water wells close to the river were contaminated, but deeper wells had Hg concentrations below the detection limit.     

Heavy metal and arsenic distributions in soils surrounding Palapye, Botswana： An evaluation of environmental impact of coal mining and combustion in a sub-arid region

Coal is an important natural resource in Botswana. The best coals so far found occur in the Morupule coalfield, west of Palapye, where nearly 8000 million tons have been identified （Carney et al., 1994）. In this study we investigate the environmental impact of the mining and consumption of the high-ash, medium-calorific value bituminous coal in the eastern part of Botswana, which may serve as a reference for other coal mines and coal-based power stations around the globe. More than two hundred surface soil samples and three profile soil samples were collected around Morupule Colliery, Morupule Power Station and Palapye.     

Arsenic and antimony contamination in the vicinity of Yata gold mine, Guizhou, China

The ores of the Yata gold mine in China are rich in arsenic and antimony, so the exploitation of this mine may also lead to the release of As and Sb to adjacent environments, such as stream water, stream sediment, soil, plants, and crops. To understand the environmental impact of mine tailings, samples of water, sediment, soil, plant and crop were collected and analyzed. In summer of 2005, the tailings dump was seriously flushed by a heavy flood, and the mine waste was transported far away. Samples were collected in December of 2004 and January of 2006, respectively, and the impact of the flood on the release of toxic elements was evaluated. The result shows that the Yata creek, which drains the mining area, was severely contaminated by As and Sb. The dissolved As and Sb in water are 86-1140 μg/L and 65-370 μg/L, the particulate As and Sb are 38-2100 μg/L and 25-420 μg/L, whereas As and Sb in the sediment are 190-760 μg/g and 69-210 μg/g, respectively. In water environment, As and Sb show a similar feature to SO4^2- since As and Sb exist dominantly as anions--H2AsO4^-, HAsO4^2- and SbO3^-. In contrast to Fe, Cu, Pb, Zn, which migrate mostly in particulate form, As and Sb tend to transport in dissolved form.     

Selected aspects of studies of sediments from the Ebro River （Spain） and the Dobczyce drinking water reservoir （Poland） within the frames of the European and national research projects

Mineral and organic matter either soluble or suspended are transported by the rivers and when deposited in the bed of the river or in the water reservoir, sediments are formed, whose chemical composition may serve as a fingerprint of the history of the ecosystem. The results of the studies of sediments in water systems （river catchments, reservoirs） can be used not only for the evaluation of the current state of the ecosystem but also to prevent any dangerous environmental changes. Bottom sediments can in many ways accumulate both suspended and soluble components. The process is influenced by several factors like pH, red-ox potential, oxygen content, interactions, etc. The complexity of those phenomena causes that in order to study the accumulation processes of compounds in sediments the application of various analytical techniques is required. The authors participate in two big projects on sediment studies. The AquaTerra Project is the EU funded project on understanding river-sediment-soil-groundwater interactions for support of management of river basins and catchment areas. Our group＇s studies are focused on mercury determination and its speciation in sediments and fish from the Ebro River in Spain. The Dobczyce Project is the national project funded by the Ministry of Education and sciences of Poland which is also a EU member country. The latter covers many aspects of accumulation and fate processes of chemical compounds in sediments of the reservoir which supplies 60% of drinking water to about one million population in the city of Krakow in Poland.     

Antarctic Glacial Retreats and the Records of Sea Level Change in Deposits at the North Bank of the Shenzhen Bay,South China

In view of the huge ice cover of 24.5 X 10⁶ km³ in Antarctica, which accounts for over 90% by volume of the ice body on earth, the movement of Antarctic glaciers is a major control on global sea-level change and climatic fluctuation. As recorded in the Quaternary deposits in King George Island, West Antarctica, three rapid ablations can be recognized at 11000, 9000 and 6100 years ago and the global climate within the past 6000 years is characterized by small-amplitude warm-cold fluctuation. Intertidal deposits at the north bank of the Shenzhen Bay suggest a periodic variation in sea level in about every 670 years over the last 6000 years with low sea levels recorded in the periods of 5500-4900, 3900-3600, 2400-2200 and 1300-1200 years ago. Between these periods the sea level rised for about 80 cm on average. The modern warming climate in the last century corresponds with a rise of sea level at the rate of 2~3 mm/a. A state key project under the Antarctic Science & Technology Program (No. 905-02-04-03) and is partially financially supported by the Natural Science Foundation of Guangdong Province.     

Temporal and dimensional distribution of sulfate-reducing bacteria （SRB） groups and quantity in the sediments of Lake Erhai

The purpose of the thesis is to analyze the temporal and dimensional distribution of sulfate-reducing bacteria （SRB） groups and quantity in Lake Erhai. In April and September 2005, two sediment cores were collected from Lake Erhai. SRB groups were analyzed by PCR with six-groups primers designed according to the specific 16SrDNA sequence. FISH （fluorescence in-situ hybridization） was established with the oligonucleotide probe （SRB385） and utilized to analyze SRB quantity in the sediments. The results showed that in the sediments of Lake Erhai four SRB groups were detected except Desulfobacterium and Desulfobacter, meanwhile Desulfovibrio-Desulfomicrobium were detected only in autumn; different SRB groups had different temporal and dimensional distribution, and each group in autumn is distributed more widely than in spring; FISH used to count SRB in the sediments of fresh lake was set up successfully; the analysis of correlation between the sediment＇s depth and SRB quantity had statistical meaning （P〈0.05） . The result showed that SRB quantity showed a decreasing trend with increasing depth. Through the analysis of randomized block designed analysis of variance, the difference in SRB quantity between spring and autumn also had statistical meaning （P〈0.001）, which revealed SRB quantity in autumn was larger than in spring; the result of FISH showed that there were some SRB in the deeper sediments in which no above-mentioned six SRB groups were detected by PCR. SRB groups in the sediments of Lake Erhai were rich, and the quantities of SRB groups in autumn were larger than in spring; possibly there were uncultivable SRB groups in the sediments of Lake Erhai.     

Heavy metals in soil of the Baikal biosphere reserve （in connection with degradation of fir forests of the northern macroslope of Khamar-Daban Range）

The Baikal biosphere reserve （Khamar-Daban Range, South Pribaikalye） demonstrates withering of fir forests, progressing from 1970＇s. As to possible reasons of this phenomenon concerned, there are many viewpoints; the main among them is the technogenic influence of the Baikalsk pulp and paper plant （BPPP） and Irkutsk industrial center （IIC） on forest ecosystems. Geochemical characteristics of the snow cover within the Baikal reserve, investigated by us earlier indicate that degradation of fir forests at present does not result from the transfer of industrial emissions from BPPP and IIC to places of growing fir forests. Aimed at further revealing of reasons of fir forests withering, we investigated the chemical composition of soil （as a substratum feeding trees） in the Baikal biosphere reserve. We studied brown mountain-forest and alluvial-turf soil predominating in the reserve, which are characterized by weak differentiation profiles, in places （at the slope＇s bottom） by significant （up to 2.5-3 m） thickness. Samples of 250-300 gr. were collected from the genetic soil horizons distinguished visually and roughly by the thickness. Total contents of heavy metals （HM）-Cu, Cr, Ni, Zn, Co, Mn, Cd, Li, Rb, Sr, their mobile modes of occurrence （m/m）, extracted by acetate-ammonium buffer with pH=4.8 were determined. We also measured the concentrations of metals in the insoluble （fixed） residue （FR） obtained after extracting their mobile modes by atomic-absorption （Perkin-Elmer -503 spectrometer） method. The analytical error by this method does not exceed 10 %.     

Evaluation of the frequency of micronucleus in epithefial cells of children exposed to arsenic and heavy metals pollution in a mining area of Mexico

Mining industry is one of the most important economical activities of Latin America, where As, Pb and Cd are commonly associated with the extraction of precious and base metals. Mining activities become a source of contamination if control measures are not adapted to avoid the pollution of soils by these potentially toxic elements （PTE） for the human, because they have the capacity to produce damage to the DNA generating a genomic instability in the individual and this directly can lead to the development of chronic diseases like cancer. The considered population of greater risk is the infantile since they have an exceptional vulnerability to the acute or chronic effects of environmental toxics and in addition have a higher susceptibility to these PTE compared with the adults. For that reason, it is assumed that the infantile population exposed to soil contaminated by the mixture of As, Pb and Cd, has damage in the DNA of its cells and this provokes a greater susceptibility to develop neoplasics processes or other environmental diseases. Individual sensitivity to the cytogenetics effects produced by the polluting agents or their metabolites is based on the differences in the magnitude of the repair systems induction, reason why it is necessary to determine the genotoxicity in exposed children by means of the evaluation of a damage biomarker that allows to establish a biological meaning to predict the adverse effects in health.     

Distribution of nutrients and chlorophyll a in the Three-Gorges Reservoir, China

1IntroductionUp to now,eutrophication is still a problem af-fecting water quality in many developing countries.Themost important nutrients causing eutrophication arephosphates,nitrates and ammonia(Lijklema,1995;Horne and Goldman,1994).Eutrophic waters are…     

XRF Determination of 17 Trace Elements in Geological Samples Using an Extended Compton Scattering Correction Procedure

This work is intended to explore a fast and effective apoproach to the determination of various trace elements in geological samples throuth improvement and simplification of the method developed by Reynolds (1963,1967),Absorption correction was made for the Fe content to eliminate the effect caused by inconsistency in mass absorption coefficients among the samples.A computer-aid regression analysis was performed on a number of standards of various compositions,which resulted in a set of calibration equations for directly converting X-ray intensities to concentrations.An analytical error of 10-30% was involved in the analyses of most elements.     

X-ray flurorescene (XRF) determination of trace rare-earth elements in geological samples using ion-exchange-resin membrane technique

Rare-earth elements in samples of geological interest were separated from other elements and concentrated onto ion-exchange membrane through ion-exchange procedures. The membrane was then used to determine the REE by X-ray fluorescence spectrography. In comparison with the traditional “thick-specimen” approach, the requirement of sample (REE oxides) in this method was reduced from 10 to 1 mg. Variable-internal-standard-quantification method was adopted to determine the relative concentrations of REE collected on the membrane. The area density of the sample was controlled at about 0.0003 g/cm², so that the matrix effect could be eliminated to a satisfactory extent. Interference calibration between the spectro-lines and the background determination was also improved, with the detection limit reaching 2.5×10^?6g.     

ICP-MS测定地质样品中37个元素的准确度和长期稳定性分析

对Elan6100DRC型ICP-MS近五年来所测得的国际地质标样BHVO-1（玄武岩）和AGV-1（安山岩）中的37个元素的测定值以及仪器灵敏度的长期漂移情况进行了统计分析（共计146次）.结果表明,几年来ICP-MS所测数据的长期稳定性和准确度都较好,除个别元素Li（BHVO-1）、Be（BHVO-1））、Cr（AGV-1）、CS（BHVO-1）和Pb（BHVO-1）的相对误差（与参考值比较）接近或略大于10%外,绝大多数元素的相对误差和相对标准偏差（RSD,测定值之间,n=146）都在5%以内;仪器灵敏度并不是随着时间一直往下漂,有的是往上漂的,也有上下漂的,即使是在同一时间内,有的元素灵敏度往上漂,而有的往下漂.常用的内标法无法较好校正这种漂移,而需要采用内外标相结合的校正方法.不同批次,210个各种地质样品中Rb、Sr、Zr和Nb的XRF和ICP-MS分析结果对比情况表明,绝大多数样品中Rb、Sr、Zr和Nb的ICP-MS和XRF的测定值的相对误差小于10%.以上的分析结果表明,我们实验室所建立的以密闭高温高压消解技术为样品前处理方法,以模拟地壳样品中元素天然丰度比的基体匹配校正标准溶液为外标和以Rh为内标结合外标校正的ICP-MS多元素分析方法具有非常好的准确度和长期稳定性.     

Proton-induced X-ray emission measurements of trace elements in water samples collected from an Indiana coal mining locality

A new method of simultaneous multi-elemental analysis, Proton Induced X-ray Emission (PIXE), was used to detect trace elements in waters associated with a coal strip-mining operation in southern Indiana. Stream, pond, and ground water samples were collected and analyzed monthly from, or near, Sulphur Creek in Sullivan County. The concentrations of 26 major and trace elements were determined in samples from eleven locations: K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, As, Se, Br, Rb, Sr, Mo, Cd, Sn, Sb, I, Ba, Hg, Pb, and U. Elemental concentrations fluctuated considerably throughout the 13-month sampling period and also among sampling sites. Nickel, Zn, As, Cd, Mn, Fe, and Ca were highest in the upstream water which was most acidic (pH = 2.9–4.0) because of old unreclaimed mining operations. The highest values recorded were Ni = 1662 ppb, Zn = 4953 ppb, As = 26 ppb, Cd = 93 ppb, Mn = 5063 ppb, Fe = 63 ppm, and Ca = 325 ppm. The concentrations of these elements decreased downstream as the pH of Sulphur Creek increased which was likely due to the influence of the calcareous glacial till cover in the area and the recent mining activity which disturbed overburden containing a high percentage of calcareous materials. Lead, I, Br, and Ti values were highest (661 ppb, 86 ppb, 70 ppb, and 45 ppb, respectively) in the ground water from the coal seam (pH approximately 7). Other elements which were relatively high in the pH 7 waters closest to the current mining operations (pond, stream, and groundwater) included K (17 ppm), Sr (3408 ppb), Ba (173 ppb), As (14 ppb), Rb (16 ppb), Sn (14 ppb), and Cu (3840 ppb). The highest Cu concentration was recorded at the point where drainage water from the mine entered Sulphur Creek. Gallium, U, Hg, and Mo were found in low (< 13 ppb for Ga and Hg; < 205 ppb for Mo and U) concentrations and only in the ponds within the mine.     

冷蒸气原子荧光法测量地球化学样品中痕量汞

用冷蒸气原子荧光法测量地球化学样品中痕量汞,对载气流量、试液酸度、硼氢化钾浓度等进行了试验。工作曲线线性范围为0～4μg/L,方法检出限为0.002 3μg/g,精密度RSD%为1.1~5.0。方法用国家一级地球化学标准物质中汞的测定,结果与标准值一致。     

锆石微区原位同位素和微量元素测定的新进展

文章简述了二次离子探针质谱(SIMS)、激光剥蚀等离子体质谱(LA-ICP-MS)和激光剥蚀多接受等离子体质谱(LA-MC-ICP-MS)等3种锆石微区原位同位素和微量元素测定方法的原理和优缺点;针对U-Pb定年、铪同位素、锂同位素、多种元素的同时测定,以及仪器改进、测试方法创新、标样研发等方面的新进展进行了评述。     

The importance of second order activation in the determination of trace elements in geological samples by instrumental neutron activation analysis

This paper deals with the disturbance of INAA trace element determinations in rocks by second order activation. The degree of error in the determination of Gd by Eu in rocks is checked by experiments and compared with results of computer evaluations. The consequence of the Dy-interference for the determination of Ho was also calculated. Hints to avoid these interferences are given.     

Rare earths,other trace elements and iron in Luna 20 samples

The results of the analysis by neutron activation of six samples from the Luna 20 mission and one sample of < 1 mm fines from Apollo 16 are reported. The concentrations of the rare-earth elements (REE) in the samples of fines from Luna 20 and Apollo 16 are less than those found for corresponding materials from the mare areas but a negative Eu anomaly is still present. The concentrations of the REE in fines from Luna 20 are only about two-thirds as great as in the sample of Apollo 16 fines, but the concentrations of Co, Sc and Cr are greater by factors ranging from 1.5 to 2.3.     

ICP-MS在新疆、青海区调样品测定中的应用

本文以敞开式四酸溶样,电感耦合等离子体质谱测定了新疆、青海区调样品中的Co、Mo、W、Pb等元素,并把ICP-MS、ICP-AES和XRF三个大型仪器对新疆卡克-色帕巴衣地区样品的测定结果进行了比较,确定了区调样品元素分析方法的配套方案,并对溶样过程进行了一系列的优化,其方法检出限和精密度均符合DZ0130.4-2006及补充说明中1﹕5万化探样品标准要求。经国家标准物质验证,结果与标准值相符。优化的分析方法快速灵敏度高,能用于地球化学填图计划中分析测试任务, 同时也用于日常大规模多元素分析。     

海伦市土壤主要微量元素空间分布特征

以海伦市研究区1 175件表层(0~20 cm)土壤样品主要微量元素(B、Cu、Mn、Mo、Zn)的实测含量为研究对象,采用地统计学与GIS相结合的方法,对土壤微量元素的含量及空间分布特征进行分析。结果表明:研究区表层土壤中B和Mo含量较缺乏;Mn和Mo的块金效应大于75%,空间自相关性弱,B、Cu和Zn块金效应在25%~75%之间,属于中等空间相关,空间变异主要受到自然因素影响;B和Cu的空间分布相似,由中心向四周逐渐减少,Mn和Mo含量呈明显带状分布,Zn含量北部高于南部。微量元素之间既存在着共生关系,也可能存在拮抗关系。土壤有机质含量、成土母质、土壤类型和土地利用对微量元素均有不同程度的影响。