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1.
This paper presents the geochemical study of sediments along Ube, Suo-Oshima, and Kasado Bays in the Seto Inland Sea of Japan. We examined the distribution and abundances of 13 elements (As, Pb, Zn, Cu, Ni, Cr, Sr, Ca, Fe, Ti, P, Mn, and total S) in 40 coastal and river sediment samples, to evaluate the factors controlling their abundances, possible sources, and environmental implications. Average concentrations of As, Pb, Zn, Cu, Ni, and Cr at Ube were 12, 26, 86, 16, 43, and 92?mg/kg, 6, 25, 31, 8, 9, and 29?mg/kg at Kasado, and 5, 20, 28, 3, 5, and 18?mg/kg at Suo-Oshima, respectively. Average As, Pb, Zn, and Cr concentrations at Ube were comparable or enriched relative to those of the upper continental crust and Japan upper crust, whereas most major elements, Cu, and Ni were depleted at Kasado and Suo-Oshima. Enrichment factor values show low to moderate enrichment of Zn, Ni, and Cr, whereas As and Pb show significant contamination at some sites, suggesting contributions from anthropogenic sources. Anthropogenic contributions of most metals mainly originate from natural processes; however, As and Pb ranges of 73–79 and 66–81?%, respectively, confirm their anthropogenic contribution. Factor analysis and correlation matrices suggest that elevated metal concentrations at Ube, especially in samples located in the river basin, may be controlled by Fe–Mn oxy-hydroxides. Deposition of metals at Kasado and Suo-Oshima might be controlled by non-ferrous metal (i.e., aluminosilicates), sediment grain size, or source rock composition (granite and gneiss).  相似文献   

2.
The anthropogenic contribution of trace metals to settling particulate matter (SPM) and surficial sediments was determined on the high-energy continental shelf adjacent to Sydney, Australia. Settling particulate matter and surficial sediment was collected in the vicinity of a major sewage outfall and at five control sites on the middle shelf (80-100 m water depth). Sediment traps were deployed on 10 occasions for up to 2 weeks during the summer and winter of 1995 and SPM was analyzed for Ag, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn. Cobalt, Fe, Mn and Ni act conservatively in SPM and in sediments regionally and are used as normalizing elements to determine anthropogenic enrichment. Surficial sediments and SPM are enriched in Ag, Cr, Cu, Pb and Zn near a major ocean outfall and at four of the five control sites, although sewage particles contribute < 5% of trace metals in the total sample. Silver is the most sensitive trace metal tracer for establishing the presence of sewage particulate matter. Sewage particulate matter flux near the outfall was estimated using a two end-member mixing model and is below 0.5 g m(-2) day(-1) during all deployment periods. The mean sewage particulate matter flux at sampling locations 30 km and 60 km north of the outfall are <0.13 g m(-2) day(-1) and <0.01 g m(-2) day(-1), respectively, indicating an efficient dispersal of anthropogenic material on this high energy continental shelf.  相似文献   

3.
The macrobenthic community structure and characteristics of sediments were studied in samples collected seasonally at five stations in the lower mesotidal Douro estuary, Portugal. Sediment characterisation included grain size distribution, total-recoverable metals (Al, Fe, Mn, Zn, Cu, Cr, Pb, Ni and Cd), acid-volatile sulphides (AVS) and simultaneously extracted metals (SEM) and total organic matter contents. Spatial variation surpassed temporal variation both in terms of environmental parameters and community structure. Clear anthropogenic contamination in terms of Zn, Cr, Cu and Pb, and a positive SEM-AVS, indicating the potential bioavailability of these metals, were detected on the north bank of the estuary. Multivariate analysis revealed that in addition to natural sediment characteristics, the anthropogenic metal contamination was influencing the macrobenthic community structure. In fact, greater concentrations of Zn, Cr, Cu and Pb were associated with lower number of species and/or diversity. Finally, the dry weight-normalised metal concentrations appeared as a more useful tool than the SEM-AVS model in predicting disturbance of the macrobenthic community in the studied area.  相似文献   

4.
Vertical distribution (0–15 cm) of the macrobenthic community and its relationships to natural sediment characteristics and trace metal contents and bioavailability were studied at five locations in the lower Douro estuary, Portugal. An analysis of vertical metal distribution, for the interpretation of anthropogenic impact on the estuarine sediments, was also investigated. Sediment characterisation included organic matter, grain size, metals (Al, Fe, Cu, Pb, Cr, Ni, Cd, Zn and Mn), acid volatile sulphide (AVS) and simultaneously extracted metals (SEM). The macrobenthic community had low diversity (14 species), was dominated by small size opportunists and seemed to be controlled mainly by natural factors such as grain size distribution, Al and Fe contents and sediment depth. The vertically heterogeneous distribution of macrobenthic community appears to affect redox status of the sediments and consequently metal bioavailability. Despite anthropogenic contamination in terms of Zn, Cu, Pb, Cr and Ni having already been detected in the north bank, the analysis of vertical distribution was essential for the identification of current anthropogenic contamination in terms of Zn, Pb and Cd in the south bank.  相似文献   

5.
烟台近岸典型生态区沉积物重金属形态分布及其污染状况   总被引:3,自引:0,他引:3  
运用Tessier连续提取法,对烟台海岸带3个典型生态敏感区表层沉积物重金属Cr、Cu、Cd、Pb、Zn、Ni的形态分布和污染状况进行了分析研究。结果表明,研究区域中河口区与排污口区重金属Cr、Cu、Cd、Zn和Ni的含量较高,尤其是Cd污染严重。养殖区基本符合海洋沉积物质量第1类标准;重金属Cr、Cu、Pb、Zn和N...  相似文献   

6.
Distribution and sources of heavy metals in the sediment of Xiangshan Bay   总被引:2,自引:0,他引:2  
Heavy metals in the surface sediments and sediment core from the Xiangshan Bay, a mariculture base on the coast of the East China Sea, were determined by inductively coupled plasma mass spectrometry(ICP–MS) in order to evaluate their levels and sources. The results showed that the levels of Cu, Pb, Zn, and Cr in the sediments of the bay have been generally influenced by anthropogenic inputs since the founding of the People's Republic of China. In particular, Cu and Zn were polluted to some extent, as evidenced by high enrichment factors. Organic matter, grain size, wastewater discharge, and low energy hydrodynamic environment played dominant roles in the heavy metal enrichment in the sediments. The ratio of terrigenous source to marine biogenic deposit of trace metals in the sediments was calculated, revealing that terrigenous inputs were the main source of Cu, Pb, and Zn, while biological pellets contributed much more to the enrichment of Cr and Cd. Considering the influence of biological sources on the enrichment of Cd and Cr, and the fact that the sediment has been polluted by Cu and Zn, the development of mariculture and discharge of wastewater into the Bay should be restricted.  相似文献   

7.
Spatial distribution of selected contaminants in the surface sediments of Santa Monica Bay (SMB), California was investigated. Sediments were analyzed for DDTs (DDT and metabolites), polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), linear alkylbenzenes (LABs) and coprostanol. Effluent samples from the Hyperion Treatment Plant (HTP), which discharges treated municipal wastewater effluents into SMB, were also analyzed. The inter-correlation in the distribution trends of contaminants was examined. The concentrations of contaminants were interpolated in a geographic information system to visualize their spatial distribution in the Bay. Inventories of the contaminants were also estimated.The concentrations of coprostanol, LABs and PCBs are very high only in the vicinity of the sewage outfall whereas PAHs and DDTs occur widespread in the Bay. The poor correlation of DDTs with LABs, PAHs or coprostanol content confirms the historic origin of DDTs and their absence in the contemporary wastewaters. Moderate correlation of DDTs with PCBs implies historic deposits as a major origin of PCBs. There are hot spots of DDTs at water depths of 60 and 100 m and the inventory of DDTs in Bay sediments is insignificant compared to that estimated in the Palos Verdes Shelf which extends from the southern edge of Redondo Canyon around Palos Verdes Peninsula. The concentration of toxic contaminants was examined according to published sediment quality guidelines. About 20 stations contain p, p′-DDE and/or total DDTs above ERM and, PCBs between ERL and ERM indicating potential for adverse biological effects.  相似文献   

8.
南澳岛是广东南澳县的主岛, 周边海域的环境保护被置于当地社会经济发展的重要位置。为此, 2004年 5月、7月选择以水产养殖为主的后江湾和白沙湾及以旅游为主的青澳湾作为研究对象, 对南澳岛海域重金属的 含量、分布、富集及污染状况进行了调查与评价。结果表明该海域重金属元素的平均含量为Cd: 0.19mg.kg-1, Cr: 26.86mg.kg-1, Cu: 20.71mg.kg-1, Ni: 22.78mg.kg-1, Pb: 35.67mg.kg-1, Zn: 79.48mg.kg-1, 低于近岸经济发达海域, 但高于受人类活动影响较小的外海; 在分布特征上表现为湾口高于湾内, 养殖区高于非养殖区的总趋势, 但在各海湾之间重金属含量并无显著差异, 表明南澳岛海域重金属主要来源于地表径流输入。该海域以城市污水中代表元素Cu (Cf = 2.75), Pb (Cf = 2.27)富集为主; 以海洋沉积物质量标准、沉积物质量基准和美国太平洋沿岸基线值评价, 南澳岛海域环境质量均处于健康状态, 但其潜在污染效应仍值得关注。  相似文献   

9.
Heavy metal concentrations in the surface sediments of specially managed Ulsan Bay were investigated to determine metal distribution, pollution status and its ecological risk using pollution indices (enrichment factor and geo-accumulation index), potential ecological risk index and sediment quality guidelines (SQGs). The order of mean concentration (mg/kg) of metals was Zn (361.9) > Cu (95.6) > Pb (90.7) > Cr (64.7) > Ni (32.2) > Co (16.6) > As (15.8) > Cd (0.40) > Hg (0.16) in sediments of Ulsan Bay. Spatial distribution of metals in sediments showed a significantly higher concentration near industrial complexes, indicating that metal pollution is caused by anthropogenic sources. The results of enrichment factor (EF) and geo-accumulation index (Igeo) showed that sediments were significantly accumulated with Cu, Zn, As, Cd, Pb and Hg, indicating moderate to very severe enrichment (pollution) by these metals. Based on the potential ecological risk index, Hg and Cd posed a very high and a considerable potential ecological risk. Cu and As posed a moderate potential ecological risk, while, other metals (Cr, Co, Ni, Zn and Pb) rarely posed any potential ecological risk to the coastal environments. The sediments in Ulsan Bay showed a very high level of ecological risk, dominated by Hg and Cd. Metal concentrations in sediments were 80% for Cu, 96.7% for Zn, 50% for As, 70% for Pb and 50% for Hg above the threshold effects level (TEL), respectively.  相似文献   

10.
《Marine Chemistry》2001,73(2):153-171
Particles from the Whites Point/JWPCP outfalls operated by the Los Angeles County Sanitation District (LACSD) have been discharged onto the Palos Verdes (PV) shelf, Southern California, since the late 1930s. Since the early 1950s, they have made a significant contribution to the sedimentary deposits on the shelf. In order to study the transport and diagenesis of organic carbon (OC) and associated trace metals, replicate sediment cores were collected during 1996 and 1997 at four different sites at the ∼60 m isobath on the PV shelf, and analyzed for OC, Ag, Al, Cd, Cr, Cu, Mn, Ni, Pb, and Zn. We conclude from these results that a significant fraction of OC and associated heavy metals were transported laterally on silt particles from shallower environments. Cross-shelf transport of sediments caused multiple peaks in measured profiles of OC and trace metals at site 6C, 2 km away from the outfall. The same mechanism is likely to contribute to a concentration decrease that is smaller than that expected from decreases from the Whites Point outfall emissions. Based on Pb/OC ratios in sediments, deposited in 1971, and comparisons to the outfall from the same year, we estimate that 50±10% of the OC deposited in the early 1970s, now buried at 30–50 cm depth, had oxidized since that time, implying a half-life of about 26 years for the outfall-OC, as an upper limit. The average OC oxidation rate at peak depth (about 2 mg C cm−2 year−1) is, however, only about 10% of the present-day OC accumulation rate (20 mg C cm−2 year−1), which itself is adding not much more than 1% per year to the post-1950s OC inventory (∼1500 mg cm−2). We furthermore estimate that the OC inventory in PV shelf sediments in 1971 was equivalent to about 35% of that emitted by the outfall. OC and trace metal inventories did not decrease in the period 1981 to 1997, contrary to those of other contaminants such as DDTs and PCBs.  相似文献   

11.
Denitrification influences the nitrogen budget in estuaries by removing fixed nitrogen from the inorganic pool; rates are dependent on both geological and geographic conditions as well as increasing anthropogenic impacts. In this study the effects of copper (Cu), chromium (Cr), zinc (Zn), cadmium (Cd) and lead (Pb), on the denitrification pathway were evaluated in subtidal and intertidal sediments of the Douro River estuary. Dinitrogen, N2O and NO2 production rates were measured in triplicate slurries of field samples under different treatments of metal concentrations. Results demonstrated that similar metal amendments led to different site responses for denitrification, suggesting that variations in sediment properties (metal concentrations, grain size, organic matter content, etc.) and/or differences in denitrifying community tolerance modulate the level of metal toxicity. Denitrifying communities in subtidal muddy sediments were not affected by increasing concentrations of metals. In contrast, intertidal sandy sites revealed high sensitivity to almost all trace metals tested; almost complete inhibition by Cr (95%) and Cu (85%) was observed for 98 and 79 μg per gram of wet sediment respectively, and by Zn (92%) at the highest concentration added (490 μg per gram of wet sediment). Moreover, the addition of trace metals stimulated N2O and NO2 accumulation in intertidal sandy (Zn, Cu, Cr and Cd) and muddy sediments (Cu and Zn), demonstrating a pronounced inhibitory effect on specific steps within the denitrification enzymatic system. In summary, the results obtained suggest that, according to the type of estuarine sediment, trace metals cannot only reduce total N removal from an estuary via denitrification but also can enhance the release of N2O, a powerful greenhouse gas.  相似文献   

12.
《Marine Chemistry》2001,73(2):125-152
We report here bioturbation and sediment accumulation rates determined from replicate sediment cores at four different sampling sites on the Palos Verdes shelf, Southern California, using bomb fallout and natural radionuclides (137Cs, 239,240Pu, 210Pb, 234Th, and 14C), along with supporting measurements of organic carbon (OC), porosity and granulometry. Present-day particle reworking, on time scales of several months, is restricted to the upper 3 cm, with rates ranging from 13 to 200 cm2/year, as deduced from 234Thxs profiles. There is little evidence that particle reworking reached depths significantly greater than 5 cm. Post-1963 (or post-1971) sediment accumulation rates ranged from 0.7 to 1.4 g/cm2/year (equivalent to 1.1–1.8 cm/year for surficial sediments), as calculated from Pu and Cs isotope profiles, with little change over time or distance from the outfall. Lateral transport of older sediment and multiple sediment sources on the Palos Verdes shelf is suggested from radiocarbon measurements on foraminifera and bulk sedimentary organic matter at two sampling sites, which showed variable, old and refractory sources of OC. Pre-1953 sediments accumulated at rates that were at least 0.4 g/cm2/year (≥0.3 cm/year), based on 210Pbxs dating. Given the abundance of sediment sources to the Palos Verdes shelf, the high sedimentation rates, and shallow particle mixed layers, contaminant-enriched layers should continue to move deeper into the sediments.  相似文献   

13.
为了解大亚湾沉积物中重金属分布及污染状况,于2016年8月对大亚湾海域表层沉积物中重金属元素(As、Cd、Cr、Pb、Zn和Cu)展开调查,并将获得的各元素含量与粒度、Fe、Mn和总有机碳(TOC)等相关理化要素进行相关性分析。结果表明:大亚湾沉积物中重金属受陆源输入影响较大,含量基本呈现为沿岸高、湾内低的趋势,总体质量较好,基本符合第一类海洋沉积物质量标准要求;澳头湾和范和港附近海域人类活动密集,重金属含量较高。通过相关性分析结果发现,大亚湾重金属主要来源为岩石的风化和侵蚀、工业污水排放和渔业养殖等;Cu与铁锰氧化物结合性弱于其他元素,在还原性环境中被沉积物吸附形成金属Cu硫化物可能是喜洲岛附近海域Cu元素含量异常高值的原因;作为湾内有机质主要来源的水生浮游生物的生长状态对Cr、Zn和Pb含量影响较大;Cr、As和Pb与粉砂结合为主,Zn与粘土结合为主。  相似文献   

14.
江苏王港潮滩重金属Pb、Zn和Cu的累积规律   总被引:1,自引:0,他引:1  
对15年来江苏王港潮滩重金属Pb、Zn和Cu积累规律研究表明,王港潮滩WG05点位现代平均沉积速率为4.13 cm/a。王港潮间带重金属垂直方向的含量具有趋同性,从表层向下逐步降低,具有明显的表聚和亚表聚特征,王港潮滩Fe与Li的相关系数非常显著,超过了0.90,这些潮滩重金属来自岩石风化的可能性较大;Pb、Cu、Al则与铁元素呈负相关,表明王港潮滩沉积物中的重金属Pb、Cu的含量受人为因素的影响较大。归一化后,Cu、Zn的归一化值在15年内相当稳定,其中Cu的波动范围在0.4~2之间,Zn在1.5~2.6之间狭小的范围内波动;这说明王港潮滩的Cu、Zn积累主要来自于地壳风化,受物源和沉积环境等自然因素控制较大,受人类活动影响较小。而Pb归一化以后在4个柱状样中都表现出随时间的变化发生了较大的波动。Pb、Cu为该区域的主要污染因子。  相似文献   

15.
According to the results of the comparative study performed of the littoral sediments sampled in small inlets of Kandalaksha Bay (the White Sea in the Russian Arctic), the metals (Fe, Mn, Cu, Zn, Pb, Cr, and Li) occur mainly in a biogeochemical-stable mineral-incorporated form, which comprises 77–99% of the total metal content. The ratio of the liable form, which is easily extracted by a weak acid, is on average 3.2% for the total Fe, 2.0% for Mn, 1.7% for Cr, 5.6% for Pb, 5.8% for Zn, 6.5% for Cu, and is negligible for Li. The concentrations of the most studied trace metals are below the threshold level according to the environmental quality guidelines (the sediment analysis). The ratio of the metal forms evidences the natural origin of the elevated concentrations of both Zn and Cr in the sediments.  相似文献   

16.
Abstract

Surface sediment samples (60 μm‐2 mm, and < 60 μm fractions) from the Waiwhetu Stream, Lower Hutt City, New Zealand, were leached with dilute HCl to remove the mobile heavy‐metal fraction. Cd, Cr, Cu, Pb, Zn, Al, Fe, and Mn analyses of the leachates show that sediments of the upper reaches area of the stream are generally uncontaminated. In contrast, sediments in the lower reaches area are highly contaminated, despite clean‐up measures in the late 1970s. Lead and Zn are the most significantly enriched metals with concentrations over 1000 mg kg?1 adjacent to some drains. In the polluted zone, metals originate from either upward remobilisation from underlying sediment (contaminated in the early 1960s and 70s) or more recent industrial spillages. Similar trends exhibited by Cd, Cu, Cr, Zn, Pb, and Al indicate that a proportion of the metal enrichment downstream probably results from a naturally higher clay content of sediments near the mouth of the stream. Fe and Mn show reverse trends to the other metals, indicating that a high proportion of these two metals occurs in substrate different to that of the other metals. The orange brick‐coloured sediments of the upper reaches of the stream indicate oxides upstream; the black sediments in the lower reaches indicate sulphides downstream.  相似文献   

17.
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.  相似文献   

18.
Sediment cores from a transect of sealochs, Etive, Sunart, Nevis, Duich, Broom and Torridon in N.W. Scotland were analysed for the trace metals lead, copper, and zinc. In addition, sediment cores from the Clyde Sea Basin (Loch Fyne, the Gareloch, Clyde dumpsite) and from the Irish and Celtic Seas were analysed as possible source areas for contaminated particles. The sediment cores were dated using excess 210Pb and 137Cs, and Al normalisation was used to correct for sediment compositional effects. All cores showed increased concentrations of all trace metals (and M/Al) towards the surface, with a maximum of 280–500% above background being observed in Loch Etive. Only cores from Duich and Torridon (Zn/Al and Pb/Al) and Etive (Zn/Al) did not continue to show an increase in trace metals to the uppermost samples. The burden of atmospherically derived trace metals accumulated over the past 100 years was compared with similar published burdens from a series of freshwater lochs adjacent to the sealochs. Plots of excess 210Pb (used to correct for sediment focusing) against atmospherically derived Pb showed a series of linear relationships of systematically decreasing gradient towards the north-west, away from potential urban sources of lead. It was calculated that 49% (15–77%) of the Pb but only 3% (1–4%) of the Zn and 2% (0–3%) of the Cu reached the sealochs from atmospheric sources. The remaining trace metals deposited in the sealochs came from marine particles. Using trace metal ratios as an indicator of pollutant provenance, it was shown that the trace metals came predominantly from the Irish Sea. There was no evidence of trace metals derived from the Firth of Clyde basin. It was concluded that trace metal contamination from the Clyde and the surrounding industrialised urban area was mainly deposited in the estuary and the Clyde Sea basin with its adjoining sealochs, such as the Gareloch and Loch Fyne.  相似文献   

19.
文章于杭州湾南岸潮滩布设3个采样断面并采集沉积物样本,采用地质累积指数法和潜在生态危害指数法评价重金属污染状况及其生态风险。研究结果表明:沉积物基本为粗粉砂和细砂,由海向陆粒径逐渐变细且分选性逐渐转差;所有站位重金属含量均值从高到低依次为Pb、Zn、Cu、Cr、Cd和Hg,断面重金属含量从高到低依次为高潮滩、中潮滩和低潮滩,Cu、Hg和Pb的空间分布差异较大;本次采样调查结果与邻近区域数据和同区域历史数据相比有所不同;根据地质累积指数评价结果,Cu、Pb和Zn有不同程度的污染;根据污染指数和潜在生态危害指数评价结果,Zn、Cd和Cr与地质累积指数评价结果区别较大,研究区重金属总体污染程度为低度和中度,除Cd外其他重金属处于低生态危害水平,研究区重金属总体生态危害为低度。调查和研究成果可为分析区域重金属环境影响和制定污染控制对策提供科学依据。  相似文献   

20.
利用在胶州湾采集的47组同站位多介质样品,进行了痕量金属Pb、Zn及其它环境因子的化学成分测试,讨论了胶州湾水-沉积物-生物系统中Pb、Zn的生物地球化学总体特征及其在各介质平面上的分布,揭示了胶州湾水-沉积物-生物系统对陆源物质输入的响应.垂向上表层沉积物是Pb、Zn组分的富集带,该系统中的生物相对于其所处水环境具有显著的富集作用,生物体中Pb、Zn生物浓缩系数分别为36、935;横向上,Pb、Zn在底层水和沉积物介质中的分布主要受控于河口,即高值区分布于胶州湾的各个主要河口区,特别是在沉积物中金属组分浓度的高值区主要集中分布于胶州湾的东部.而孔隙水中Pb、Zn的高值主要分布于水交替较弱的海域,如红岛前缘.但生物体中的痕量金属组分化学场空间分布规律与上述各介质的化学场均不吻合,亦即是生物体中痕量金属组分的浓度与其所处环境中的同名金属组分浓度无关.作者认为,生物对痕量金属组分的富集并不简单地取决于它所处环境介质中同名金属组分的总量,而存在形态上的选择性.通过回归分析揭示了孔隙水对生物体中Pb、Zn的富集贡献较大.  相似文献   

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