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1.
Twenty-seven samples of suspended sediments collected on Millipore filters from the St. Lawrence estuary were directly analysed for Si, Al, Ca, Mg, Na, K, Fe, Ti, Mn, Ni, Co, Cu, Cr and Zn by X-ray fluorescence using standards prepared from suspended matter collected by continuous flow centrifugation. Calibration curves prepared from the analysis of these standards could be directly used in calculating the weight percent of elements for the unknown samples, if the weight of the total suspended matter on the filters did not exceed 25 mg.  相似文献   

2.
Phosphorus and metals bound to organic matter were separated from coastal sediments of Harima Sound in Seto Inland Sea, Japan by extraction with NaOH and fractionated by Sephadex G-25 chromatography. Phosphorus and metals were determined in the eluates by a multi-channel, inductively coupled plasma-atomic emission spectrometer. Phosphorus and Cu, Zn, Fe, Mn, Ni, Cr, Co and Ti bound to organic matter with high molecular weights (OMHMW) (MW ? 5000) were found to be present in the sediments, but no Mo or V were found. The technique provides minimum estimates of the amounts of P and metals bound to organic matter. These organic complexes show surface enrichment in a sediment core (0–20 cm) and their contents decrease with depth. Also, the amounts of eighteen elements, namely: P, Fe, Mn, Zn, Cu, Si, Al, Ti, Pb, Co, Ni, Cr, Mo, V, Na, K, Ca and Mg, in H2O, ammonium acetate at pH 7 and 5, hydrogen peroxide, hydroxylamine hydrochloride and hydrogen fluoric acid soluble fractions have been determined with a selective chemical leaching technique for the 210Pb-dated sediment core sample. Considerable amounts of P (6–19%) and Cu (5–21%) were associated with organic matter, in contrast to other metals such as Fe, Mn, Zn, Ni, Cr, Co and Ti which were associated with sulfide and silicate.  相似文献   

3.
菊花岛周围海域38个站表层沉积物的铁、锰、铝、钛、磷、有机质、氮、铜、锌、铅、镉、镍和汞等化学要素含量的Q型因子分析计算表明,本区可划分为三个化学元素沉积区:1.海流悬浮沉积区;2.近岸波浪作用区;3.波浪海流作用区。柱状沉积物中铁等化学元素的迁移、富集受氧化——还原界面的控制。  相似文献   

4.
2008年11月末在青岛近海和胶州湾11个站点采集表层和底层海水中的悬浮颗粒物(SPM)样品,经消解后用等离子体发射光谱法测定了Al、Ca、Fe、Mg、Mn、Ti和Ba、Co、Cr、Cu、Ni、Pb、Sr、V、Zn共15个金属元素以及P的含量,结合SPM和元素含量聚类分析的结果探讨了秋末冬初青岛近海SPM的来源以及金属元素组成的影响因素.SPM含量范围在1.7～16.1mg/L之间,平均为7.9 mg/L;SPM来源以陆源风化产物为主,生物生产有较小的贡献.SPM中Ti、Fe、Mn、Mg、Al、V、Co、Sr和Ni的含量相对恒定,且主要受陆源输入的控制;Ca和P除受陆源影响外,生物生产亦有附加贡献.离陆地相对较远的区域表层海水SPM中Pb、Zn和Ba、Cr、Cu的含量较高,特别是Pb和Zn的富集因子较大,可能受到了潜在的污染影响.Ti的恒定性以及与SPM的良好相关性代表着在青岛近海可用Ti作为颗粒物陆源指示元素,且优于Al.  相似文献   

5.
The results of geochemical studies of particulate matter in the water mass over the hydrothermal field at 9°50′ N on the East Pacific Rise are presented. The particulate matter was tested in background waters, in the buoyant plume, and in the near-bottom waters. The contents of Si, Al, P, Corg, Fe, Mn, Cu, Zn, Ni, Co, As, Cr, Cd, Pb, Ag, and Hg were determined. No definite correlations were found between the ele-ments in the background waters. Many of the chemical elements correlated with Fe and associated with its oxyhydroxides in the buoyant plume. In the near-bottom waters, microelements are associated with Fe, Zn, and Cu (probably, to their sulfides formed under fluid mixing with seawater). The matter precipitated in a sed-imentation trap was similar to the near-bottom particulate matter in the elemental composition.  相似文献   

6.
南海铁锰结核(壳)的元素地球化学研究   总被引：1，自引：0，他引：1  
本文利用南海11个铁锰结核(壳)样品的化学分析资料,研究了铁锰结核(壳)中Fe,Mn,Cu,Co,Ni,Pb,Zn,Cr,K,Na,Ca,Mg,Si,P,Al,Ti,Sr,Ba及∑REE的元素地球化学特征。结果表明:(1)铁锰结核(壳)以高Fe,∑REE,低Mn,Cu,Co,Ni等元素为主要特征;(2)铁锰结核(壳)中Fe,Mn间无明显相关,而Fe与∑REE,∑Ce,∑Y呈弱的正相关,Mn与∑REE,∑Ce,∑Y呈明显的正相关,结壳中Fe,Mn与Si,Al,Cu Co Ni呈负相关;(3)结核(壳)中Mn/Fe与Cu/Ni,Ce/La呈负相关,Mn/Fe主要受Mn控制;(4)结核(壳)中Fe,∑REE等元素主要来自南海陆源中酸性岩类的风化、淋滤和沉积。  相似文献   

7.
东海陆架晚第四纪沉积物化学成分及物源示踪   总被引：11，自引：0，他引：11  
东海陆架EA1孔和EA5孔沉积物化学成分变化范围较大。与东海陆架表层沉积物相比，钻孔沉积物的Si,Al,Mg,Mn,Ti,P,Ba,Zr,Co,Ni,Cu,Zn,Cr明显偏高，而Fe,Na,Ca,Sr,Li,U明显偏低，与全球大陆地壳化学组成相比，钻孔沉积物的Si,Li,Rb,Ba,Th,Zr,Hf,Cu,Zn,Pb偏高，而Al,Na,Ca,Mg,Fe,Mn,Ti,P,Sr,U,Co,Ni,V,Cr偏低，钻孔沉积物的化学成分在垂向上具有明显变化，主要受岩性和沉积环境的控制，钻孔沉积物中元素的富集因子（EF）均小于10，接近于1，表明钻孔沉积物主要来自大陆地壳，一些元素因分异或外来物质加入而富集，一些元素则因分异带出而亏损，钻孔沉积物源区的DF值判别表明，钻孔沉积物与现代黄河，长江沉积物均有亲缘关系，可能是在末次冰期最盛期，由于气候带南移，干旱区域扩大，在古长江搬运沉积物中类似现今黄河沉积物的干旱组分明显增加，从而导致了地球化学示踪结果的长江与黄河双重性，或者说古气候的变化导致了古长江搬运物质成分的变化。  相似文献   

8.
Suspended matter was collected at 30 stations in the Baltic and Kattegatt, at the thermocline and at the bottom, and analysed for Na, Ca, Mg, Si, Ti, Al, Fe, Mn, Ba, Sr, Ni and V. The composition of the suspended matter varies considerably, but can be described as a mixture of: (1) 12–25% terrigenous detritus with much Si, Al, Ti and Fe; (2) 75–88% biological matter with much Ni, V and Ba; and (3) some Mn-oxyhydroxide.The annual efflux of water from the Baltic is about 460 km3, with a suspended load in the Baltic straits of ～1.2–3.6 mg ash material l?1 These values imply that much Si, Ti, Al, Fe, Sr, Ni and V and particularly much Ba and Mn are lost from the Baltic in the suspended load.The average suspended matter is richer in Mn(5×), Ba(2.5×), Sr(4×) and V(1.8×) than permanently depositing Baltic sediments. These constituents are relatively enriched in pelagic deposits, i.e. it is likely that much Mn, Ba and V in deep-sea sediments derive from the continents via suspended transport. This conclusion is supported by the similarity between suspended matter and average Atlantic pelagic sediment.  相似文献   

9.
The ratio of marine to fluvial suspended matter in the Scheldt Estuary was calculated by applying factor analysis to a data set of elemental concentrations. The data set consisted of 98 samples collected under various river discharge conditions. Each sample was analysed for the concentration of Cr, Pb, Fe, Mn, Ni, Co, Ba, Zn, Cu, Cd, S, Ca, Sr, Ag, Sn and Na. Five linearly independent processes were found to describe the variability of the elemental concentrations: (1) the supply of fluvial material to the mixing zone; (2) manganese oxidation in the transition area between the anoxic upper estuary and the oxic lower estuary; (3) the supply of marine material to the mixing zone; (4) a phytoplankton bloom in the lower estuary; and (5) the formation of insoluble metal sulphides in the anoxic high-turbidity zone. Scores of the first and third factor were used to calculate the ratio of marine to fluvial suspended matter in the mixing zone. Information on the origin of both the inorganic and organic fraction of suspended matter was obtained in this way.  相似文献   

10.
红树植物红海榄叶化学组成研究   总被引：4，自引：0，他引：4  
对红树植物红海榄叶的基本化学成分水分,灰分,灰分中酸不溶物,灰分中S(SO42-),粗蛋白,粗脂肪等及氨基酸和微量元素的组成和含量进行了系统的分析测定。其基本化学组成各成分含量分别为:水分(69.18%),灰分(3.04%),灰分中酸不溶物(0.094%),灰分中S(SO42-)(0.052%),粗脂肪(7.75%),粗蛋白(7.14%);测得了红海榄叶中17种氨基酸,其总含量为10.7mg/g,其中人体必须氨基酸有7种,占所含氨基酸总量约26%;采用全谱直读等离子体原子发射光谱仪对红海榄叶进行了31种微量元素的分析测定,测得了其中18种元素的含量,红海榄叶中含有丰富的人体必须的矿物质元素。  相似文献   

11.
Water quality parameters associated with siltation (non‐volatile and volatile suspended solids), oxygen depletion (chemical and biochemical oxygen demand), nutrient enrichment (N, P), toxicity (Pb, Zn, Cu, Cr, Ni, Cd), and human pathogenic micro‐organisms (coliforms, faecal coliforms, faecal streptococci) were measured in baseflow and stormflow from a residential catchment in Hamilton, New Zealand, from November 1979 to December 1981. A macro‐invertebrate survey was conducted. All parameters, except nitrogen, were predominantly associated with particulate material, and closely followed suspended solids behaviour during storm runoff. The concentrations of these particulate parameters are linearly related to suspended solid concentrations, which implies a reasonable consistency in the particulate source material, probably attributable to the uniform stable land use. The runoff was enriched with nitrate (from septic tank seepage) and the particles by Zn, Pb, and Cu. There was little or no enrichment of the particulates with phosphorus, nitrogen, organic matter, Cr, or Ni relative to catchment soils. Ni, Cr, and Cd were generally below detection limits. Dissolved reactive phosphorus and NH4 +‐N levels were low and unimportant in total P or N leaving the catchment. Most organic matter was particulate and only slowly degraded, and consequently the biological oxygen demand was only a small fraction (c. 13%) of chemical oxygen demand. Interpretation of the water quality data allows some tentative predictions to be made of potential receiving water impacts. It is doubtful that urban runoff will cause significant oxygen depletion, although the high level of organic‐rich particulate material could lead to a deterioration of receiving water sediments and affect benthic invertebrates. Urban runoff may be an important source of nutrients, but (apart from nitrate) its importance depends on the amount of suspended material in the runoff rather than increased input of nutrients from urban‐related activities. Bacterial counts indicate a poor water quality. The impact of metals will depend largely on the bioavailability of the particulate‐bound fraction. The key to the understanding of transport, treatment, and impact of most potential pollutants in urban runoff is probably their association with particulate materials.  相似文献   

12.
The concentrations of Si, Al, Ti, Fe, K, Ca, Mg, P and Mn, before and after chemical leaching, in particulate matter from waters off the west coast of Scotland have been measured in vertical profiles at two seasons. The distribution of Si and Ca are shown partly to reflect temporal changes in biological production in different waters. The distributions of Al, Ti, Fe, K and Mg have been used to distinguish different sources and types of suspended alumino-silicates, and to trace probable circulation patterns in the water mass.While Si and Ti contents of the particulate matter are unaffected by mild chemical leaching, large amounts of other elements, notably Mg, K and Al, can be removed by this treatment. Presumably, these losses indicate preferential release of these elements from octahedral and interlayer sites in clay mineral lattices.The distribution of particulate P covaries with non-silicate Fe in the surface waters, while in bottom waters, high concentrations of particulate Fe and Mn are associated. The relationship of Fe and P is considered to be due to the presence of particulate ferriphosphates derived from runoff. The particulate Mn and Fe in deep waters is produced by the precipitation of dissolved metals released from bottom sediments by diagenesis.  相似文献   

13.
Two cores recovered in the eastern Mediterranean were analysed for major, minor and trace elements. The primary chemical composition of the sediment is different at each location, probably because the lithological sources and the relative biogenic contributions differ.

Carbonates are important for the concentration of Ca, Mg and Sr, whereas aluminosilicates determine the concentration of Si, Al, K, Li, Y and Be, and to a lesser extent that of Fe, Cr, Ti, Mg, Zn and Zr. In sapropels, organic carbon and sulphur seem to be closely related. Bromine, Mo, P, Fe, V, Cu, Zn, Co, Ni and Cr are closely associated with organic and sulphidic compounds. The concentration versus depth profile for organic carbon in two sapropels points to a rapid establishment of conditions that gave rise to sapropel formation, followed by a gradual transition back to “normal” conditions.

The primary composition is overprinted by diagenetic processes. Sulphate-reducing conditions occurred during and just after sapropel deposition. A progressive oxidation front mechanism, which became active after sapropel deposition, is responsible for additional major geochemical changes. This diagenetic phenomenon has strong implications for the chemistry of Fe, Mn, Ni, Co, Zn, Cu, Cr, V, U, As and Sb.  相似文献   


14.
Dissolved and particulate trace metals (Cu, Cd, Pb, Zn, Ni, Fe and Mn) measured at six stations along the Scheldt estuary in October/November 1978 are compared with more recent data. Based on Ca content in the suspended matter, three distinct geochemical regions could be distinguished: the upper estuary (salinity 1–7) dominated by fluvial mud, mid-estuary (salinity 7–17) where the composition of the suspended matter remained relatively constant, and the lower estuary where marine mud prevailed. Re-suspension of sediments is the major factor controlling the composition of the particles in the upstream region. Anoxic conditions prevailed in the upper part of the estuary extending to a salinity of 15 in 1978, while at present the seaward boundary of the anoxic water body is located at less saline waters. Furthermore, the present-day metal load is much lower than in 1978. As a consequence of the changed situation, maxima in dissolved concentrations of redox-sensitive metals in the mid/lower estuary have moved as well, which affects the trace metal re-distribution pattern. In the anoxic zone, exchange processes between dissolved and particulate metal fractions were strongly redox regulated, with Fe and Mn as excellent examples. Iron was removed from the dissolved phase in the early stages of mixing resulting in an increase in the suspended particulate matter of the leachable ‘non-residual' Fe fraction from 2 to 3.5%. Due to its slower kinetics, removal of Mn from solution occurred in mid-estuary where oxygen concentrations increased. Cu, Cd and Zn on the contrary were mobilised from the suspended particles during estuarine mixing. External inputs of Pb, and to a lesser extent of Cu, in the lower estuary resulted in the increase of their particulate and the dissolved concentrations. Calculated Kd (distribution coefficient) values were used to assess the redistribution between the dissolved and particulate phase of the investigated metals. Due to the existence of the anoxic water body in the upper estuary, the importance of redox processes in determining the Kd values could be demonstrated. The sequence of Kd values in the upper estuary (Fe, Cd, Zn, Pb > Cu > Ni, Mn) is significantly different from that in the lower estuary (Fe > Mn > Pb, Ni, Zn, Cu, Cd). Thus, in such a dynamic estuary single metal-specific Kd values cannot be used to describe redistribution processes.  相似文献   

15.
Marine colloidal material (1 kDa–0.2 μm) was isolated by cross-flow ultrafiltration followed by diafiltration and freeze-drying from surface waters of the Gulf of Mexico and the Middle Atlantic Bight (MAB), as well as from estuarine waters of Galveston Bay. Elemental characterization of isolated colloidal material included organic carbon (OC) and selected trace metal (Cu, Pb, Zn, Cd, Co, Ni, Cr, Be, Fe, Al, Mn, V, Ba, and Ti) determinations. It was found that levels of these metals in marine colloids ranged from <0.1 to 50 μg/g colloidal matter, except for Fe which generally had a concentration >120 μg/g. Most metals (Cu, Pb, Zn, Ni, Al, Mn, V, and Ti) had an average concentration >1 μg/g while concentrations of Cd, Co and Be were usually <1 μg/g. Metal concentrations (μg/g) in isolated colloids were, in general, higher in Galveston Bay than in the Gulf of Mexico, suggesting either high abundance of trace metals in estuarine waters or differences in organic matter composition. Higher colloidal metal concentrations in the MAB than in the Gulf of Mexico might be due to higher terrestrial inputs in the MAB. Colloidal metal concentrations (μg/g) were generally lower than those in average soils, continental crust and suspended particles. However, metal/aluminum ratios (Me/Al) in isolated marine colloids were significantly higher than those for average soils and continental crust. Most importantly, colloids had a metal composition and metal/OC ratio (Me/C) similar to humic substances and marine plankton, suggesting that marine colloids largely originate from planktonic sources and are composed of predominately organic components. The Me/C ratios of Galveston Bay colloids followed the sequence of Cu>Ni, Cr, Zn>Mn>Co>Pb, Cd, which is similar to the Irving–Williams order except for Mn, suggesting that the interaction of metals with marine colloids is determined by the affinity of metals for specific organic ligands.  相似文献   

16.
Elemental mass-balance of material carried by major world rivers   总被引：3，自引：0，他引：3  
An estimate of average river particulate matter (RPM) composition was bàsed on analyses of more than 40 elements in the Amazon, Congo, Ganges, Magdalena, Mekong, Parana and Orinoco rivers, to which were added literature data for 13 other major world rivers, covering the whole spectrum of morphoclimatic features. Geographic variations of major elements in RPM are mostly linked to weathering types and to the balance between weathering rate and river transport. As a result of chemical erosion, Al, Fe and Ti are enriched in RPM with respect to the average parent rock, while Na, Ca, Mg and Sr are strongly depleted. These figures are directly related to the relative importance of dissolved and particulate transport in rivers; this has been computed for each of 40 elements. In order to study weathering on a global scale, the total observed elemental fluxes (dissolved + particulate) have been computed and compared to theoretical ones. The latter were derived from the elemental content in the average parent rock and the total quantity of weathered material, computed from the Al ratio in RPM and in parent rock. Observed and theoretical fluxes are balanced for the less mobilized elements (rare earths, Co, Cr, Cs, Fe, Mn, Rb, Si, Th, Ti, U and V) for which no enrichment relative to Al is noted in RPM, and for B, Ba, Ca, K, Mg, Na, Sr which are relatively depleted in RPM due to their high dissolved transport. Additional fluxes have been found for Br, Sb, Pb, Cu, Mo, Zn and are possible also for Ni and P. This is reflected by marked enrichments in RPM relative to Al for the poorly or moderately dissolved transports (Pb, Cu, Zn). Several hypotheses involving either the natural origin (volcanic dust, marine aerosols, geochemical fractionation) or the artificial origin (worldwide pollution) are discussed to explain these discrepancies, assuming river transport and weathering either to be in a steady state on a global scale or not. However, none of them can fully account for these additional fluxes. It is most likely that these excesses have multiple origins, anthropogenic or natural or both. The comparison between RPM and deep-sea clay compositions emphasizes the prime influence of river input on oceanic sedimentation of Si, Al, Fe, Ti, lanthanides, Sc, Rb, V, etc. A few elements such as Zn, Sb, occur in excess in RPM as compared to deep-sea clays; in order to balance this excess, a remobilization of these elements out of the sediment can be considered. Finally, the enrichment of Co, Cu, Mn and Ni in deep-sea clays compared to RPM is discussed and attributed to several sources and processes.  相似文献   

17.
Between 1980 and 1984 extensive studies were carried out in the Baltic Sea on trace metals (Cd, Co, Cu, Fe, Hg, Mn, Ni, Pb and Zn) in water, suspended matter and sediments. The results enabled the influence of different factors on metal distribution patterns to be considered. The vertical profiles of dissolved and particulate metals in waters of the central deep basins reflect influences caused by oxygen deficiency and anoxic conditions in near-bottom water layers. Peculiarities at Station BY15 in the Gotland Deep included high dissolved Fe, Mn and Co concentrations and remarkable enrichment of Zn (0.64%), Cd (51 μg g−1) and Cu (0.15%) in particulate matter from the anoxic zone. Manganese-rich particles were accumulated above this layer.In fine-grained soft sediments below anoxic deep waters, maximum contents of Cd, Cu and Zn were observed, relative to other coring sites, between Bothnian Bay and Lübeck Bight. The Hg content in sediments probably reflects the joint flocculation with organic matter. Land-based sources seem to play the leading part for maximum lead contents.  相似文献   

18.
Total and weak-acid-soluble trace elements in suspended matter from the Duwamish River and Elliott Bay were determined from samples collected in February and September 1980. The results indicate that Mn scavenging in the water column is coincident with enrichments of Cr, Ni, Cu, Zn, and Pb in the suspended matter, suggesting a possible enrichment of these trace elements in a hydrous Mn oxide phase. This process occurs primarily in the sub-surface waters of Elliott Bay. Since mass balance calculations show a net export of Mn out of the bay, this mechanism may be an important means of transporting toxic trace metals from polluted estuaries and embayments to cleaner coastal environments.  相似文献   

19.
In 1984, on a transect covering the whole Baltic Sea and parts of the adjacent North Sea, 160 water samples were taken and analysed for their concentrations of particulate and dissolved metals. In addition, the suspended materials were investigated for their elemental bulk composition.The particulate fractions represented from about 5% (Cd, Cu and Ni) to 50% (Fe and Pb) of the total (particulate plus dissolved) concentrations. For some elements (Ba, Cd, Cu, Pb and Zn), the particulate matter from the surface microlayer was enriched with respect to those suspended materials taken from 0.2 m depth. This could reflect the atmospheric input of metal-rich aerosols. In anoxic deep waters, maximum contents of Zn (6400 μg g−1), Cu (1330 μg g−1) and Cd (12 μg g−1) were observed in the particulate matter, indicating sulphidic forms. On the other hand, under oxic conditions the distribution coefficients (Kd) decreased with the water depth (Cd, Fe and Pb).Relative to global background levels, the particulate matter contained metal “excesses” amounting to more than 90% of the total contents (Cd, Mn, Pb and Zn). Automated electron probe X-ray microanalysis (EPXMA) revealed that the elemental composition of sediments is mainly governed by post-depositional processes of early diagenesis and is only weakly related to the composition of suspended matter in the overlying water body. For instance, in relation to surface mud sediments of the central Baltic net-sedimentation basins, Zn, Cd, Cu and Mn had 30–100% higher levels in the suspended materials. The general pattern of metal contents of particulate matter taken from 10 m depth on a transect between the Bothnian Bay and the North Sea were—possibly as a result of anthropogenic inputs—rather similar for Pb, Zn and Cu. For Fe and Mn, the distribution patterns along the transect were probably governed by the natural loading characteristics and by the biogeochemistry of those elements.  相似文献   

20.
Metal concentrations of Cu, Fe, Mn, Ni, Pb and Zn in an infaunal facultative deposit-feeding bivalve, the Baltic clam Macoma balthica, in the Gulf of Gdansk (southern Baltic Sea) were assessed and compared to selected concentrations of metals in the environment. Between October 1996 and September 1997, dissolved and easy extractable (by 1M HCl) metal fractions of total suspended particulate matter (TPM) in the overlying water and of surficial sediments (<63 microm) were measured monthly at five sublittoral sites in the Gulf of Gdansk, and accumulated tissue metal concentrations in M. balthica were determined simultaneously. The study highlights the importance of sediment geochemistry as a factor modifying ambient trace metal bioavailabilities. Surficial sediments appeared to contribute most to the accumulation of Cu and Pb in M. balthica, reflecting the high metal availability in the Gulf. Assimilation of Cu from sediments is controlled by Mn components possibly through an inhibitory effect of Mn oxyhydroxides, while Pb accumulation from sediments depends on the organic content of the sediment. A dual metal uptake pathway, with a suspended particulate-bound fraction and surficial sediments, was apparent for Mn and Zn. Partitioning of Mn in sediments was related to the concentration of labile Fe, with increased levels of Fe tending to inhibit the accumulation of Mn by the clam. Tissue accumulated Zn might have been altered by the clam's internal regulation, making Zn tissue concentrations, to some degree, independent of its environmental level. The principal source of Ni accumulated by the clams exists in the soluble phase.  相似文献   

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