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1.
The powerful mass-flow of melt water during the brief period of spring thaw provides a surge of pollutants and causes extremely toxic short term conditions. Together with the increase in total metal concentrations during this period, a redistribution in metal speciation occurs that increases the proportion of more toxic forms. Concentrations of ion-exchangeable fractions of nickel (Ni), copper (Cu), aluminium (Al), and manganese (Mn) show strong negative correlations with pH. The sum of complex metal species shows a strong positive correlation with total organic carbon (TOC). A data analysis model based on relationships observed between key parameters and metal behaviour together with gidrological data allowed an assessmrnt of the metal impact on waterbodies from accumulated airborne pollution (Ni, Cu) as well as from accelerated leaching from watersheds (Al, Mn).  相似文献   

2.
Abstract

The analysis of extractable trace elements was carried out on 434 soils using 0.1 N HC1 as the extractant for copper, manganese, iron, zinc and cobalt, 0.2 M ammonium oxalate at pH 3.0 for molybdenum and boiling water for boron. Results indicated that on the average from about 1 to 20 percent of the total element content of the soil uas extractable, the percentage varying with the element. Comparing the amount of extractable elements in the 0–15 cm and 15–30 cm layers indicated that only manganese, zinc and boron were significantly different.

Correlation studies showed that the pH significantly influenced the quantity of manganese, iron, zinc and boron extracted, while organic matter influenced copper, manganese, zinc, cobalt and boron and clay content the copper, manganese, iron, zinc, cobalt and boron.  相似文献   

3.
To characterize potatoes according to their geographic origin and variety, 10 mineral and trace elements (Mg, Cr, Mn, Fe, Ni, Cu, Zn, Sr, Cd, and Ba) were determined in Italian potato samples. The data collected were successively elaborated using statistical techniques, namely, linear discriminant analysis (LDA). LDA was able to classify and discriminate the potatoes from Fucino both from those of other areas of Italy and from those of the four provinces of Abruzzo. A net separation between the Fucino potatoes and those of the other areas of Abruzzo was observed. LDA discriminated also the three potato varieties cultivated in the Fucino basin. The presence of these 10 mineral and trace elements was a good means for establishing the geographical place of origin of Fucino potatoes.  相似文献   

4.
Sulphur and heavy metal deposition in northern Finland (= in Lapland) and the Kola Peninsula were surveyed using Scots pine bark samples. Sulphur concentrations in bark close to the Kola smelters were on an average twice as high as on the Finnish side of the border. The Cu and Ni concentrations near the smelters were almost 100-fold the mean values in northern Finland. There was a marked decrease in the sulphur and heavy metal concentrations with increasing distance from the emission sources. The effects of emission from the Kola Peninsula were evident in Finland only close to the border, especially in the eastern parts of Inari (NE corner of Lapland) where the Cu and Ni concentrations were 2- to 6-fold those in western Lapland. The sulphur and heavy metal concentrations in most of northern Finland were low. However were the concentrations of Cr in bark in the SW corner of Lapland considerably high, due to the emissions from the Tornio refined steel plants.  相似文献   

5.
Quantitative methods of analysis by spark source mass spectrometry have been used to determine the total trace element content of the surface horizons of 10 arable Scottish soils derived from parent materials of different geological origin and used for earlier trace element surveys. Other methods have been used to supplement these analyses for 12 elements including the major elements, and results for a total of 62 elements in the 10 soils are reported. The results are discussed in terms of the geological nature of the soil parent material making use of 62-element soil fingerprints for visual comparison. It is concluded that the total trace element contents of a Scottish soil corresponds to that expected on the basis of the geochemistry of its parent materials and that the influence of agricultural operations on soil contents is of secondary importance. Average soil contents for most elements are closely similar to published values for crustal abundance.  相似文献   

6.
Abstract

The amount of sulphur (S), nitrogen (N), and organic carbon (C) in different layers of soils from some Alfisols varied considerably with location. The amount of S extracted by different extractants as a percentage of the total S was in the order of organic (3.5%)>0.05 (N) NH4OAc+0.25 (N) HOAc (1.9%)>0.1 (N) H3PO4 (1.8%)>0.025 (N) CaCl2 (1.8%)>0.03 (N) NaH2PO4 (1.7%)>0.001 (N) HCl (0.6%). In all the soil series SO4 2?‐S mineralization decreased up to the second week after incubation, followed by a slight increase up to the fourth week, a subsequent decline up to the sixth week, and a slight increase up to the eighth week. The C:N, C:S, N:S, and C:N:S ratios averaged 9.4:1, 63.7:1, 6.9:1, and 94:10:2.08, respectively.  相似文献   

7.
Cystine concentrations (g/16g N) in plant tissue declined more under S deficiency conditions than methionine. In N-balance trials with rats the negative effect of S deficiency on S amino acid composition of peas and cauliflower resulted in a corresponding decrease of the biological value of the protein.  相似文献   

8.
Arylesterase activity was measured along with microbial biomass C (BC) and respiration, and H2O‐soluble and NH4NO3‐exchangeable trace elements (TE), in contaminated soils (TECS) from three long‐term field trials. The AGIR (AG) soils were contaminated only by inorganic Cd, whereas the Ambarès (AM) and Louis Fargue (LF) soils were contaminated mainly by Mn and Zn, and Cd and Ni, respectively, from past sludge application at different rates. In the AG soils, the arylesterase activity decreased with increasing Cd total concentration and solubility. In the AM soils, the arylesterase activity decreased with increased contamination, whereas in the LF soils the arylesterase activity was increased by sludge additions, with the higher values detected in soils with lower sludge incorporation rates. In the AG and AM soils, arylesterase activity was significantly and negatively correlated with H2O‐soluble and NH4NO3‐exchangeable TE, whereas in the LF soils it showed a ‘hump’‐shaped trend with sludge additions and could not be modelled. Multiple regression analysis showed significant interactions between TE, soil pH value and TOC with this enzyme activity. Respiration values of the AG soils generally increased while the BC generally decreased with Cd contamination, while different trends were observed in the AM and LF soils. No trends in the enzyme activity‐to‐BC ratios were found in relation to soil contamination. Information regarding the inhibition of arylesterase activity in TECS can be important for the management of soils co‐contaminated by TE and organic pollutants, in which the detoxification action of arylesterase may be reduced.  相似文献   

9.
The Geological Surveys of Finland and Norway, and the Central Kola Expedition, Russia, carried out an environmental geochemical mapping project, including investigation of stream water quality. The project was carried out in 1992–1993 in the border areas of Finland, Norway and Russia, covering an area of 12 000 km2, to determine the impacts of smelting industries at Nikel and Zapoljarnij. Stream water was one of eight different indicators providing an estimation of the degree and distribution of contamination in the study area. Contamination of surface water was assessed by analyses of 44 samples, 41 variables were measured on each sample. Indicators of human activities in surface waters are NO3, K, electrical conductivity (EC), SO4, Na, Cl and acidification indicated by alkalinity and pH. On the coast Na and Cl contents are also affected by marine salts. The results show considerably higher contents of K, Ca, Mg, SO4, Na, heavy metals and EC in the samples close to Nikel and Zapoljarnij smelters than those sites more distant from the polluting sources. Especially chemical effects of high emissions of Ni, Cu and SO2 on stream water quality from Nikel and Zapoljarnij smelters are clearly seen near the sources of emissions.  相似文献   

10.
Lead (Pb) pollution in and around Ulaanbaatar is of national concern, given that the Mongolian capital is home to nearly half of the country’s entire population. By comparison, Mongolian countryside is a pristine environment because of its sparse population and low industrial activity. The concentration of Pb in urban soils (average of 39.1 mg kg–1) was twice the values found (average 18.6 mg kg–1) in background territories (i.e., Mongolian rural sites). Furthermore, Pb contamination was examined by using Pb stable isotopic composition, and covariance of Pb isotopic ratios showed two groups between rural and urban soils as pristine and disturbed sites. The 206Pb/207Pb ratio, the most prominent fingerprint for Pb pollution, was 1.163–1.185 for the urban whereas values for rural soils (1.186–1.207) were analogue to the regional Pb isotopic signatures. Local coal sources and their combustion products, one of the potential Pb pollution sources in Ulaanbaatar, have significant radiogenic properties in terms of Pb isotopic composition and revealed an average of 1.25 for 206Pb/207Pb and 19.551 for 206Pb/204Pb ratios. Thus, contributions from coal firing activity to Pb pollution lower than it was assumed, and smaller range of these values measured in urban soils may be attributed to the mixing of less radiogenic Pb as a constituent of the leaded gasolines.  相似文献   

11.
Soil samples taken by soil auger to a depth of 150 mm from randomly selected agricultural fields throughout England and Wales were analysed for total As, B, Cd, Co, Cr, Cu, Hg, Ni, Pb, Se and Zn, acetic acid-extractable Cd, Co, Cu, Ni, Pb and Zn, EDTA-extractable Cd, Co, Cu, Ni, Pb, Se and Zn, ammonium oxalate extractable Ni and Mo and hot water-extractable B. Median, log-derived mean and range data are given for each element. Median values are given also by parent material and textural grouping.  相似文献   

12.
Abstract

Seasonal changes in leaf element composition were measured at 2‐week intervals in A Oregon cranberry bogs from June 1 to September 15 for a 3‐year period. Nitrogen, P, K, and Zn leaf concentrations decreased during the season while concentrations of Ca, Mg, B, Mn, and Fe increased. Periods of 30‐day minimal internal flux varied from July 15 to September 15, depending on the element. It was concluded that 2 samples, 1 from June 15 to July 15 for Mg, Mn, and Fe and 1 from August 15 to Sep‐ tember 1 for N, P, K, Ca, Cu, B, and Zn, would have to be taken to adequately diagnose the nutrient status of all of the essential elements for cranberry.  相似文献   

13.
The potential of coniferous trees as biological indicators of heavy metal atmospheric pollution was investigated. In 31 municipalities of an industrialized region, samples of wood from the trunks of red spruce (Picea rubens) were taken to determine the spatial distribution of accumulated metals. Using the annual rings, these core samples were divided into 5-yr sections to determine temporal variations. The concentrations of Mg, Al, Ca, Mn, Fe, Cu, and Zn were measured by neutron activation analysis. All metals showed the highest concentrations in the most recent wood and the bark. For the wood older than 5 yr, Mn and Zn are stable with time, Mg and Ca decrease, while Al, Fe, and Cu appear to increase. A statistical analysis showed the municipalities with the highest variations in metal concentrations; it also revealed correlations in the fluctuations of several of the metals. As expected, trees in towns near metal refineries contain higher amounts of Mn, Fe, and Al. Large variations in metal concentrations, due to factors not totally understood, were observed. Thus, red spruce is not a sensitive bio-indicator of atmospheric metal pollution.  相似文献   

14.
Different procedures to investigate dissolved trace element concentration at the transition from unsaturated to saturated zone in soils were compared by concurrent sampling of soil solution and solid soil material in this zone. The in situ sampled soil solution from the percolated water was used to measure in situ concentrations, while solid soil material was used to measure concentrations at two liquid–solid ratios using batch experiments on 250 sample pairs. The liquid–solid ratios were 2 L kg–1 and 5 L kg–1. At 5 L kg–1, the ionic strength was adjusted with Ca(NO3)2 to a sample‐specific value similar to in situ, while at 2 L kg–1, the ionic strength was not adjusted. The extracted concentrations of most trace elements exhibited a statistically significant but weak correlation (p value < 0.01) to the corresponding in situ concentrations. In the liquid–solid ratio of 2 L kg–1 extracts, Pb and Cr showed very poor comparability with the in situ equivalent. A likely cause was the enhanced dissolved‐organic‐C release in the extract due to the lower ionic strength compared to in situ conditions in combination with effects from drying and moistening soil samples. For the other elements, correlation increased in the order As < Cu, Zn, Sb, Mo, V < Cd, Ni, Co where adjustment of the ionic strength led to slightly better results. In addition to the element‐specific shortcomings, it appeared that low concentration levels of in situ concentrations were generally underestimated by batch extraction methods. The liquid–solid ratio of 2 L kg–1 extracts could only be used as a method to predict exceedance of thresholds if a safety margin of approximately one order of magnitude higher than the thresholds was adopted. The ability of the batch‐extraction methods to estimate in situ concentrations was equally limited.  相似文献   

15.
Agricultural soil samples were collected about 1 km apart over 21 km from 32 tilled/cultivated plots of yam, rice, and cassava in urban, rural, and the derelict Enyibga lead-zinc mine (EM) in the Abakaliki area, Nigeria during the rainy season in September, 1992. In the derelict mine, mean elemental contents increased in the order Cd < Ni < Cu < Mn < Pb < Zn; while in the urban, rural, and all soils combined, the order increased as follows: Cd < Cu < Ni < Pb < Zn < Mn. The overall mean distribution of all soils shows Mn and Zn to approach and exceed toxic levels, respectively. In all soils, the total mean concentrations of Cu and Ni are well below toxic levels. The Abakaliki area is less likely to be subjected to Cd-contaminated soils. Pb was excessively high at EM and, moderately high at Mgbowo Street in the urban area, but very less so in the rural areas. The rural agricultural areas of Agbaja, Nkwaegu, and Amaegu, including the isolated Ezza Road as well as the peripheral Expressway had relatively lower levels of heavy metals, pH and organic matter content than the urban conglomeration of Mile 50, Mgbowo Street, and Azuiyiokwu including the derelict mining village of Enyigba and EM; except that Ezza Road had pH and organic matter as high as the densely populated urban cultivated areas. The relationship between bulk density and organic matter was highly dependent on pH.  相似文献   

16.
氮形态和硫水平对烤烟氮、硫、钾等营养的影响   总被引:4,自引:0,他引:4  
刘勤 《土壤通报》2006,37(6):1171-1174
红壤和潮土培育烤烟,100%铵态氮、100%硝态氮和50%铵氮+50%硝氮等3种氮形态和2种硫施用量的盆栽试验研究表明,增加硝态氮肥供给比例,有利于烤烟生长,烟株叶片干重、株高、干径增加。施硫增加,各叶位全硫含量均显著增加,下部叶片明显累积较多的硫。硝态氮处理红壤和潮土生长烟叶硫含量降低。烟叶氮含量也受供氮形态影响,硝态氮供给比例增加,烟叶全氮含量均较高。供硫增加,烟叶钾含量下降;100%铵氮处理烟叶钾累积较多,NH4+没有抑制K的吸收。  相似文献   

17.
The total deposition of sulphur (S) and nitrogen (N) components in Norway during the period 1988–1992 has been estimated on the basis of measurement data of air- and precipitation chemistry from the national monitoring network. There are large regional variations in depositions with highest values in the southwestern part of Norway. Time series analysis of annual mean concentrations of sulphur dioxide (SO2) and sulphate (SO4 ––) in air, non marine SO4 ––, nitrate (NO3 ) and ammonium (NH4 +) in precipitation, shows a significant reduction in the S concentrations both in air and precipitation. In precipitation the concentrations are reduced by 30–45 percent in Southern Norway and 45–55 percent in Central and Northern Norway. Even larger reductions are observed in air concentrations with 50–65 percent reduction in Southern Norway and 65–88 percent reduction further north. For N components there are generally no significant trends in concentration levels nor in precipitation or air. The observed trends are comparable with reported trends in emission.  相似文献   

18.

Purpose

The Qixia mine is one of the largest lead-zinc mines in Eastern China and has been operational for approximately 60 years. Source identification for trace element contamination of soils in the Qixia mining area has been lacking. This report details the evaluation and source identification of trace element contamination (including Cu, Zn, Pb, Cd, Hg, Cr, As, and Ni) of soils in this area.

Materials and methods

Thirty-three soil samples from roadsides and fields in the study area were collected and analyzed. The index of geo-accumulation (I geo) was employed to evaluate contamination. Methods of multivariate statistical analysis were used to determine the probable sources of the pollutants.

Results and discussion

The analysis showed that the levels of contamination ranked in the following order: Cd > Pb/Zn> > As/Cu> > Hg > Cr/Ni. In the sampling area nearest the mine, soil samples collected from roadsides showed much higher levels of contamination than those collected from fields away from the roadways. Trace element contamination decreased as the distance from the mine increased. Contamination extended to a distance of approximately 700 m from mineral transportation routes, with the area of greatest impact at 200 m or less. Multivariate statistical analysis and ore composition data suggest that the Cu, Zn, Pb, Cd, and As found in the soil samples originate from anthropogenic sources. Ni and Cr are considered to be at natural background concentrations.

Conclusions

This study distinguished between natural and anthropogenic sources of trace element contamination in the soils of the Qixia mining area. The contamination of Cu, Zn, Pb, Cd, and As is linked to the mining activities and is likely due to the transportation of ore concentrates and tailings.  相似文献   

19.
Natural S supplies are insufficient for high crop yields. The S brought down by rain is limited, even in industrial areas, and much of it is lost in drainage. Additional supplies are needed either as fertilizers or as SO2, which vegetation readily absorbs. The margin between the minimum SO2 concentration for full growth and the concentration at which damage occurs is wide enough for distribution via the air, without deleterious effects, of such S as is available from the combustion of fuels.  相似文献   

20.
吉林省西部地区土壤微量元素有效性评价   总被引:31,自引:3,他引:31  
王德宣  富德义 《土壤》2002,34(2):86-89,93
本文研究了吉林省西部地区土壤中作物生长所需微量元素有效态含量, 并对各微量元素有效态含量满足作物生长所需的状况进行了评价。根据采集的几种典型土壤类型样品的分析,该地区土壤中Cu、B基本满足作物生长所需,Zn、Mn、Mo、Fe 低于作物生长所需的临界值,属缺乏状态。  相似文献   

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