首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
Baseline element concentrations are given for dune grass (Ammophilia arenaria), willow (Salix repens), moss (Hylocomium splendens) and associated surface soils. Baseline and variability data for pH, ash, Al, As, Ba, C, Ca, Cd, Ce, Co, Cr, Cu, Fe, Hg, K, La, Li, Mg, Mn, Na, Nb, Nd, Ni, P, Pb, S, Sc, Se, Sr, Th, Ti, V, Y, Yb, and Zn are reported; however, not all variables are reported for all media because, in some media, certain elements were below the analytical detection limit. Spatial variation in element concentration between five Frisian Islands are given for each of the sample media. In general, only a few elements in each media showed statistically significant differences between the islands sampled. The measured concentrations in all sample media exhibited ranges that cannot be attributed to anthropogenic additions of trace elements, with the possible exception of Hg and Pb in surface soils.  相似文献   

2.
The concentrations of organic matter, major elements and trace elements were determined at 15 core locations in Lake Superior and Huron. The chemical compositions of the cores are related to sediment particle size, Eh, pH, chronology and location. Concentrations of Si, Al, Ca, Mg, K, Na, and Ti, which represent the major mineral species in the sediments, are generally uniform in each core. Surface enrichments of Hg, Pb, Zn, Cu, Ni, Co, Cd, Cr, Be, V, As, Org-C, and N at many of the locations are attributed to anthropogenic inputs of these elements in recent years. Concentration profiles of Fe, Mn, P, and S are influenced by migration of these elements in the pore waters. High anthropogenic Cu loadings in Lake Superior were related to Cu mining activities in the lake basin, while high anthropogenic inputs of Ni to the Lake Huron sediments were related to Ni contamination from the Sudbury area. Sediment loading calculations show that the anthropogenic inputs of trace and nutrient elements are related to the sedimentation rate, that the inputs are dispersed over wide areas of the lakes and that inputs to Lake Superior have increased significantly since 1955. Evidence is presented that atmospheric inputs are an important source of contaminants.  相似文献   

3.
The concentrations of 15 elements (Cu, Fe, Mn, Zn, Co, Ni, Cr, Se, Cd, Pb, Hg, Ca, Na, K, and Mg) were determined in the edible parts of shellfish on sale in the local market in Gdańsk. The samples consisted of three groups--crustaceans, molluscs, and surimi--that are processed to different degrees. For the purposes of this analysis, they were dried, homogenized, and digested in an automatic microwave system. The samples were analyzed quantitatively for Cu, Zn, Fe, Mn, Co, Ni, Cr, Mg, Na, K, and Ca (F-AAS), Cd and Pb (GF-AAS), Se (HG-AAS), and Hg (CV-AAS). The elemental levels detected in shellfish were compared to those in cod, herring, pork, beef, chicken, and eggs. The recommended dietary allowance (RDA) of essential elements and the provisional tolerable weekly intake (PTWI) of toxic elements were estimated. With factor analysis of the data, taxonomically different groups of raw and processed shellfish could be distinguished.  相似文献   

4.
Depth concentration profiles of 26 elements, i.e. trace elements (As, Ba, Cd, Co, Cr, Cu, Hg, Ni, Pb, Rb, Sr, V and Zn), lithophiles (Si, Al, Fe, Mn, Na, K, Mg, Ca and Ti) and nutrients (C, P, N, S) have been established in a sediment core collected at the Respomuso Lake (Pyrenees, Spain). This high altitude lake of glacier origin was transformed into reservoir in the fifties of last century. Correlations among the depth profiles of the above elements were established. HCl-extractable elements, which are better related to bioavailability, followed the profiles of total contents. Principal component analysis was applied to establish the binding behaviour of trace elements in the sediment matrix and, in turn, to search for their anthropogenic or natural sources. It was seen that Cu, Ni, Pb, Sr and Zn clustered together, and with exception of Sr, they were not clearly associated with any major component of the sediment. Their depth profiles correlate well with each other, hence indicating their presence as a result of atmospheric pollution. Redox-sensitive elements such as Fe and Mn follow a similar trend along the vertical profile. Depth profiles of As an Co correlate well with those of Fe and Mn. Principal component analysis showed that As, Co, Fe and Mn clustered together, which confirms the close association of As and Co with Fe-Mn oxyhydroxides. As concentrations in many strata exceed the ERM value, and therefore, significant biological effects are expected. Dissolution of minerals such as pyrite, chalcopyrite and galena taking part in the mineralogy of this area accounts for the As concentration found. Ba, Cr, Rb and V were associated with the sediment matrix (aluminosilicates), hence showing low mobility.  相似文献   

5.
The concentration of major and trace elements was determined for tomato (Lycopersicon esculentumcv. Aromata F1) fruits grown in three different substrate systems. The systems were soil and rockwool irrigated with a normal nutrient solution and rockwool irrigated with a nutrient solution with elevated electrical conductivity (EC). At three harvest times, tomato fruits were analyzed for Ca, Cu, Fe, K, Mg, Mn, Na, P, S, Sr, and Zn by ICP-AES and for Cd, Cr, Mo, Ni, Pb, Sn, and V by HR-ICPMS. The concentrations of Ca, Cd, Fe, Mn, Mo, Na, Ni, Sr, and Zn were significantly different (p < 0.05) for tomato fruits grown on the different substrates. Between the harvest times different levels (p < 0.05) were shown for Ca, Cd, Fe, Mn Na, Ni, Sr, Zn Cu, K, Mg, P, Sn, and V. The concentration of Cd was >15 times higher and the concentration of Ca was 50-115% higher in soil-grown fruits than in rockwool-grown fruits. Principal component analysis applied on each harvest split the data into two groups. One group includes soil-grown fruits, and the other group includes rockwool-grown fruits with the two different nutrient solutions.  相似文献   

6.
The concentrations of organic matter, major elements and trace elements were determined at 14 core locations in Lakes Ontario, Erie and Huron. The chemical composition of the cores was related to the sediment particle size, Eh, pH, chronology and location of sampling site. Concentrations of Si, Al, Fe, Mg, Ti, K and Na, which represent the major mineral species in the sediments, are generally uniform in each core. Surface enrichments of Hg, Pb, Zn, Cd, Cu, Be, V, Org-C, N and P are observed at most locations, with their concentrations, usually much greater above the Ambrosia horizon (≈ 120 yr BP), irrespective of the depth of the horizon. The enrichment of these elements is attributed to anthropogenic inputs in recent years. Concentration profiles for Mn and S are related to the migration of these elements in the pore waters. Anthropogenic loadings of the trace metals and nutrients parallel the population and degree of industrialization of each lake drainage basin. Natural loadings parallel the sedimentation rates. Although it is not possible to evaluate the contributions of the trace metals from various sources, evidence is presented that atmospheric inputs are important.  相似文献   

7.
The concentration of 27 elements was investigated in 10 samples of precipitation from Göttingen, collected during May and September 1972. Göttingen is a non-industrial town of 130000 inhabitants, situated in a rural area, and essentially all the dissolved and undissolved material in rainwater is locally derived. Elemental concentrations in freshwater and shale are used for comparison with the dissolved elements in precipitation and the undissolved residue. The two phases have been separated after evaporation (concentration factors: 15 to 25-times). Phosphorous, Zn, Mn, and Pb are enriched in rainwater, while Si, Mg, Na, Ca, Cl, Fe, Hg, K, Li, and Al are depleted relative to average freshwater. Sulfate, Cd, and Cu have similar concentrations in rain and freshwater. The factors of accumulation between elements in residue and average shale are calculated after normalization to the Al-value. They are: ? 100 for Ag, Hg, Pb; between 10 and 20 for Zn, Cd, P, Cu, Mo; > 2 for Cr, Bi, Ni, Ba, Ti, V ; between 0.9 and 2.0 for Rb, K, Na, Li, Mg, Mn, Fe, Si, Ca; and 0.5 for Tl. The trace element accumulation is due to different anthropogenic sources: combustion of liquid petroleum fuels contributes to Ph, V, Ni, Mo, Hg, and sulfate, combustion of coal to Ba, sulfate, and chloride, and to the. readily volatile elements such as Hg, Cd, Tl, Bi, and Ag, combustion of refuse to Ag, Bi, Pb, Cd, Hg, Zn, Cr, Cu, Ba, and Mo in highly variable amounts. Fertilizers and road salts change the chemistry of soils and indirectly supply P, alkali and alkaline-earth metals to the fly dust. Modest industrial activity is responsible for high Cu and Cr concentrations. Despite the appreciable accumulation of some toxic elements, the precipitation in Göttingen is relatively pure compared to other areas. Favorable geologic conditions around Göttingen decrease the negative influences of potentially harmful airborne elements. The high carbonate content in the dust neutralizes the anthropogenic acids in the rainwater. Furthermore, the toxic trace elements are diluted, especially in the center of Göttingen, by a large amount of airborne dust.  相似文献   

8.
Changes of phenolics and chemical elements [nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), manganese (Mn), iron (Fe), boron (B), copper (Cu), zinc (Zn), lead (Pb), cadmium (Cd), chromium (Cr), nickel (Ni) and cobalt (Co)] content in needles of black pine ( Pinus nigra) as dependent on age of needles (5–6 classes) and pollution were examined. The content of ortho-diphenols (o-dPh) and total phenols (TPh) was significantly higher at a polluted site than at a control one. It increased with age of needles at both sites. At the polluted site contents of N, K, Mg in black pine needles were lower and of Fe, Ni and F were higher than at the control site. An increase of content with age of needles at both sites was detected for Ca, Fe, B and F, and a decrease for N, P, K, Cu and Ni. The content of elements in different age classes of needles is connected with their mobility. The content of phenolics is negatively correlated with main nutrients and positively with some toxic elements.  相似文献   

9.
Oleksyn  J.  Karolewski  P.  Chalupka  W.  Oleksyn  J.  Reich  P. B.  Tjoelker  M. G. 《Water, air, and soil pollution》1999,110(1-2):195-212
Pollen may serve as a biological indicator for air pollution stress in plants. However, knowledge of pollen mineral composition and its relationship to environmental and genetic factors is very limited. We studied the concentrations of macro- and micronutrients in pollen and needles for seven European Scots pine (Pinus sylvestris L.) populations grown in two 15-yr-old provenance plantations with contrasting pollution levels. One site was located near a phosphate fertilizer factory, and the other in an area free of acute air pollution. We also tested the relationship between tree age and pollen nutrient composition by sampling 60-yr-old trees of local origin in both sites. No population differences were found in nutrient concentrations in pollen. However, there were significant differences among populations in needle concentrations of K, Mg and Zn, as well as significant site x population interaction for Mn concentration. In pollen, populations at the polluted site had significantly higher concentrations of S, Mn, Al, Na, Cu, Ni and Cd, and lower Zn. Average concentrations of S, P, Mn and Cd was lower in pollen of 60-yr-old than 15-yr-old Scots pine trees. Pollen concentrations of P, K, Ca, Mg, Fe and B were similar between sites and not related to the concentration of these elements in needles. Therefore, by analyzing the chemical composition of pollen it is not possible to detect any nutritional disorders for P, K, Ca and Mg in plants, and it seems unlikely that nutrient analyses of pollen have an advantage over analyses of foliage as a bioindicator of pollution. However, enhanced accumulation by pollen of such elements as Al, S, Mn, Cu, Ni and Cd at the polluted site may adversely affect pollen function.  相似文献   

10.
Inductively coupled plasma atomic emission spectrometry. (ICP-AES), graphite furnace atomic absorption (GFAAS) and gas chromatography with an atomic absorption detector (GC-AAS) were used for the analysis of atmospheric samples collected in the Toronto area of Southern Ontario. Airborne particulate matter and particulate and soluble fractions of snow were analyzed for S, Al, Fe, Ca, Mg, P, Pb, Zn, Cu, Cr, Cd, Ni, As, and Hg. Also, determinations of organic Hg compounds in filtered snow were performed. The element concentrations in airborne particulate matter from Toronto were similar in amount to those found in other major cities and were the highest in winter. Regional differences in the chemical composition of snow were shown to be related to industrial density. The majority of elements existed in the highest concentrations in the soluble fraction of snow, except for Al, Fe, and Pb, which were largely present in particulate matter. Differences in the distribution of elements in particulate matter in fresh and old snow were observed and depended on particle size and element. The results demonstrated the usefulness of snow as an indicator of atmospheric pollution.  相似文献   

11.
镉胁迫下小麦根系的生理生态变化   总被引:24,自引:0,他引:24  
本文通过水培和砂培两种方法 ,研究了镉胁迫下小麦 (TriticumaestivmL .)根系的生理生态变化。通过研究镉对小麦根系生长发育状况 ,根系活力 ,根系对矿质元素的吸收 ,探讨镉胁迫下植物根系的生理生态效应。研究结果表明 :镉影响根系的长度、生物量、体积和根系活力。Cd2 + 在低浓度 (处理浓度低于 5mg/L)作用下 ,随处理浓度的升高 ,刺激小麦根系的长度、生物量、体积相应地升高 ;当处理浓度高于相应浓度时 ,根长度、生物量、体积相应随浓度升高而降低。镉胁迫下根系活力受到抑制。水培和砂培中 ,镉对根系的影响趋势一致 ,但是影响幅度有差异。砂培好于水培。镉影响小麦根对矿质元素的吸收 ,Ca、Cu、Fe、K、Mg、Mn、Na、Zn吸收情况不太一致。Ca、Cu、Fe、Mg、Mn、Na的吸收量随Cd2 + 浓度升高而增加 ,K、Zn的吸收量随Cd2 + 浓度升高而减少  相似文献   

12.
Abstract

The objective of this study was to assess the efficacy of soil sampling and analysis methodologies used in Canada's Acid Rain National Early Warning System (ARNEWS). During July and August of 1992, twenty‐five soil pits were sampled and analyzed for available phosphorus (P); exchangeable potassium (K), calcium (Ca), magnesium (Mg), iron (Fe), copper (Cu), manganese (Mn), zinc (Zn), aluminum (Al), sodium (Na), sulfate‐sulfur (SO4‐S), boron (B), and molybdenum (Mo); total nitrogen (N), P, K, Ca, Mg, Fe, Cu, Mn, Zn, Al, Na, sulfur (S), B, nickel (Ni), lead (Pb), and organic matter (O.M.); pH; and cation exchange capacity (C.E.C.) at three ARNEWS sites across Ontario. The soils were: i) a till‐derived Ferro‐Humic Podzol (Humic Haplorthod), ii) a Humo‐Ferric Podzol (Haplorthod) developed in coarse glaciofluvial sand, and iii) a Dystric Brunisol (Dystrochrept). The three sites were similar in chemical composition except for available P, exchangeable Ca, Mn, total Mn, O.M., and pH. Sample numbers calculated to achieve ±10% error with 95% confidence were much higher in mineral horizons than in forest‐floor horizons. Organic macro‐elements and pH were found to be the least variable parameters while micro‐elements were significantly more variable. Analyses are categorized into groups requiring similar numbers of samples. Other studies have found comparable levels of variability and their results are compared to coefficients of variation generated by the Ontario results. Variability within a pit was also observed and found to be less than that found across each 20‐ x 20‐m site but still very significant. Overall, the variability results from other studies appear to be applicable to Ontario acid soils for common analyses. Investigations observing micro‐elements, or which require high levels of accuracy, should incorporate pilot studies to ascertain the degree of variability for their location.  相似文献   

13.
Concentrations of chemical elements in tree roots including heavy metals from air pollution Total concentrations of P, S, Na, K, Mg, Ca, Al, Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd and Pb were measured in roots from beech, spruce, ash, maple and a forest herb (Mercurialis perennis). The root samples were taken from a site with an acid soil type (Saure Braunerde) and from a site with calcareous soil (Rendzina). All elements except Mn, Zn and Pb (on acid soils) and Ca (on calcareous soils) showed higher concentrations in finest roots (<1 mm diameter) compared to fine roots (1–2 mm). In the case of the toxic heavy metals, this is interpreted as a consequence of reduced root uptake due to physiological processes or to organic complexing, followed by an accumulation at the root surface. Compared with aboveground plant parts, roots show accumulation of Al, Pb, Cd and Zn, indicating reduced translocation from roots to shoots. Roots from acid soil show higher concentrations of P, Mn, and Pb than in calcareous soil. The concentrations of Al and heavy metals in the roots are considered to be a consequence of the contamination of the investigated forest sites by long-range transported air pollutants, i.e. acid precipitation and deposition of heavy metals.  相似文献   

14.
The concentrations of Hg, Cu, Pb, Zn, Cd, Fe, Mn, Cr and As were measured in groundwaters from the Upper West and Upper East Regions and the Accra Plains of Ghana. Apart from Fe, the trace metal levels for the two Upper Regions were similar. Samples from the Accra Plains had the highest trace metal concentration. However, Hg and As were undetected in all the samples. While the mean Cd, Mn and Cu concentrations for all the 3 study areas fell below the WHO limit, values for Pb and Cr exceeded the WHO limits for drinking water. Iron exceeded the limits in the Upper West Region and the Accra Plains. Overall, the most abundant elements in groundwaters were Zn, Fe and Cr.  相似文献   

15.
The study quantifies the amount of metals (Na, K, Mg, Ca, Al, Fe, Mn, Ni, Cr, V, Cu, Zn, Cd, Pb) leached from the A-horizon of a podzolic spruce forest soil in southern Sweden during 2.5 yr, and offers statistical evidence of environmental conditions of importance to metal release. Considerable losses of Pb, Cr, Ni and V may occur from the A-horizon of forest soils under conditions favoring leaching of organic matter, Fe, and Al, i.e. during periods of comparably high soil temperature and moisture. Metals with a larger fraction present in exchangeable form (Na, Mg, Ca, Zn, Cd) are more susceptible to minor pH changes. An accelerated deposition or internal production of acidic matter therefore will reduce the retention times of these elements particularly.  相似文献   

16.
Critical concentrations of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), iron (Fe), zinc (Zn), and manganese (Mn) with respect to dry matter yield end antagonistic and synergistic relationships among these nutrients were studied in which tomato (Lycopersicon esculentum L.) was grown in recirculating nutrient solution (NFT). Increments of nutrient elements in the nutrient solution increased the proportional rate of the corresponding nutrient elements. Increasing levels of N negatively correlated with plant P and positively correlated with Ca, Fe, and Zn. Iron and Mn contents of the plants were increased and N, K, Ca, and Mg were decreased as a function of P applied. Increases in K in the nutrient solution caused increases in the concentrations of K, N, P, and Zn, and decreases in the concentration of Ca and Fe. Applied Ca increased the concentrations of Ca and N, and decreased the concentrations of P, Mg, Fe, Zn, and Mn. Potassium, Ca, and Fe contents of the plants were decreased and Zn increased, while N, P, and Mn were not affected by the increasing levels of external Mg. Iron suppressed the plant Mg, Zn, and Mn contents. Synergism between Zn and Fe was seen, while P, K, Ca, Mg, and Mn contents were not affected by Zn levels. Potassium, Ca, Mg, and Fe were not responsive to applied Mn, however, N and P contents of the plants were decreased at the highest levels of Mn.  相似文献   

17.
Metal distribution and interaction in plant cultures on artificial soil   总被引:2,自引:0,他引:2  
Rye-grass, Lolium multiflorum, cultures on perlite, an artificial soil, were carried out with a basic nutrient solution (modified in each experiment), adding double distilled water when necessary to restore evaporation losses. Cultures were collected at different times, separated into roots and tops and controlled by moisture, dry weights and metallic element contents measurements. Plant chemical analyses were performed after HF-HN03-HClO4 digestion by AAS (Mg, Ca, Fe, Mn, Cu, Zn, Co, Ni, Cd, As, Pb) and flame emission (Na and K). Cultures with changes in basic nutrient solution component concentrations, with additions of potentially toxic elements (Co, Ni, Cd, As, Pb, Cu, Zn, Na) and with different periods of culture (7 to 49 days after 6 days for germination) were carried out. Measurements of metallic elements dissolution and diffusion within a perlite layer were also made. For discussion of results ionic impulsions are introduced as I = c 1/n , where c is the considered metallic element concentration and n its oxidation number. Root or top uptakes of a metallic element follow linear relationships with their ionic impulsions in nutrient solution or root, respectively. Roots and tops seem to keep constant the total ionic impulsions, sums of individual metallic elements ionic impulsions. Toxic effects were evident for total ionic impulsions greater than average values. Results are further discussed through NUTRIENT SOLUTION ? PERLITE ? ROOT ? TOP equilibria that suggest a single assimilation mechanism for roots, and two different ones for ROOT ? TOP step: (i) an osmotic permeation with root accumulation of some elements (Cu, Zn, Fe, Co, Ni, Cd, As, Pb) and (ii) a DONNAN permeation leading to top accumulation of other metals (Mg, K, Ca, Na, Mn).  相似文献   

18.
Nineteen elements, Mg, Al, Ca, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Se, Sr, Sb, Ba, As, Cd, Hg, and Pb, were determined in three types of popular herbal tea products, Gynostemma pentaphyllum, Camellia sinensis, and Morus alba. These herbal tea products, both imported and locally made products, are widely consumed in Thailand and worldwide. Microwave-assisted acid digestion was used for all of the samples, and the element contents were determined by ICP-MS. The concentrations of all elements varied among these herbal teas. Ca and Mg were the most abundant elements in all herbal samples (1384-34070 and 783-7739 mg/kg, respectively). Most elements in these herbal tea powders were also released into the infusions at different percentages depending on types of herbs. G. pentaphyllum infusion contained essential elements (Mg, Ca, V, and Fe) at higher levels than C. sinensis and M.alba infusions. Al and Ni were present at high levels in C. sinensis infusion, and Cd level was high in M. alba infusion. The daily intake of all elements from these herbal tea infusions (three cups/day) is still within the average daily intake. Therefore, it may not produce any health risks for human consumption, if other sources of toxic metal contaminated food are not taken at the same time.  相似文献   

19.
Deep sea dog sharks (Deania calcea, Centroscymnus crepidater, and Centroscymnus owstonii) were captured from the waters off western Victoria, Australia, in April and May 1998. The elements As, Ca, Cd, Cu, Fe, Hg, K, Mg, Mn, Na, Sr, and Zn were detected in the muscle tissue. The concentrations of Al, Ba, Be, Cr, Mo, Ni, Pb, and V were below the detection limits of the instrumental techniques employed (ICP-ES and GF-AAS). However, significant concentration differences between species were detected for As, Cd, Hg, and Zn. C. owstoni contained the highest concentrations of each of these elements. The concentrations of Cu, Pb, and Zn in each species were below the maximum levels permitted in food by the Australian Food Standards Code. The maximum permitted concentrations of As and Hg were exceeded in all species, and weekly consumption of 400 g of any of these sharks would result in intake of more than the FAO's provisional tolerable weekly intake. Although C. crepidator and D. calcea have strong relationships between length and mercury concentration, C. owstoni does not. Placing C. crepidator and C. owstoni in the same genus, therefore, is worth re-examination as the mechanisms for controlling mercury in C. owstoni appear to differ from that used by both C. crepidator and D. calcea.  相似文献   

20.
Baseline element concentrations are given for Spanish moss (Tillandsia usneoides), loblolly pine (Pinus taeda), and associated soils. Baseline and variability data for ash, Al, Ba, C, Ca, Cd, Ce, Co, Cr, Cu, Fe, K, La, Li, Mg, Mn, Na, Nb, Nd, Ni, P, Pb, S, Sc, Sr, Th, Ti, V, Y, and Zn are reported; however, not all variables are reported for all media because, in some media, certain elements were below the analytical detection limit. Spatial variation in element concentration among and within 0.5 km grid cells are given for each of the media. In general, only a few elements in Spanish moss showed statistically significant landscape patterns, whereas several elements in loblolly pine and in soils exhibited differences among sampling grids. Significant differences in the concentration of three elements in Spanish moss and eight elements (including total S) in loblolly pine were observed between two sampling dates (November and June); however, the absolute amount of these differences was small. Except for perhaps Ni and Pb concentrations in Spanish moss, element levels in all sample media exhibited ranges that indicate natural rather than anthropogenic additions of trace elements.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号