The influence of diet on comparative trace metal cadmium,copper and zinc accumulation in Thais clavigera (Gastropoda: Muricidae) preying on intertidal barnacles or mussels     

Blackmore G  Morton B 《Marine pollution bulletin》2002,44(9):870-876

The influence of diet on comparative metal accumulation was investigated using a predatory muricid gastropod Thais clavigera. Individuals were fed for up to 56 days on either barnacles, i.e., Tetraclita squamosa, or mussels, i.e., Perna viridis, collected from metal-contaminated and clean sites. Barnacles and mussels have contrasting metal handling strategies and, therefore, different body concentrations, intracellular distributions and detoxification systems. Field collection of prey items that accumulated body metal concentrations over a lifetime of exposure allowed bioavailability to the predator, T. clavigera, to be assessed naturally, which may not be the case for prey exposed to metals for a short time in the laboratory. T. clavigera that was fed cadmium- and copper-contaminated barnacles or mussels ingested significantly greater amounts compared to those fed conspecifics collected from clean locations. T. clavigera body cadmium and copper concentrations were not, however, significantly different between individuals fed either contaminated or clean prey. Amount of zinc ingested was similar in mussels collected from clean and contaminated environments but much less when compared to the barnacle prey. The body concentrations of zinc in T. clavigera fed mussels collected from both sites fell. In contrast, the amount of zinc ingested from barnacle prey was significantly greater from those collected from the metal-contaminated site as compared to the clean one. This was reflected as significantly greater body zinc concentrations in T. clavigera fed contaminated barnacles compared to those fed clean individuals. Copper and zinc accumulation from prey was, therefore, complex. It varied between metal and between prey type, but appeared to be related to the amount ingested and the metal handling strategy of the prey.  相似文献   

铅锌资源供需形势分析及市场前景预测   总被引：1，自引：0，他引：1  

吴荣庆  张燕如  张安宁 《江苏地质》2007,31(1):59-63

从资源保证程度、找矿前景、冶炼原料和金属产品的生产与需求、市场价格的变化趋势等几个方面,对铅锌资源的国内外市场的供需形势进行分析,并对其未来5年的市场前景进行了初步的预测。  相似文献   

Chemical contamination of a coral reef by the grounding of a cruise ship in Bermuda   总被引：1，自引：0，他引：1  

Jones RJ 《Marine pollution bulletin》2007,54(7):905-911

Bulk metal analyses of surficial sediments collected around the Norwegian Crown cruise ship grounding site in Bermuda indicated significant but localized contamination of reef sediments by copper and zinc, caused by the stripping of the tri-butyltin (TBT)-free antifouling (AF) paint (Intersmooth 460) from the underside of the hull. Highest copper and zinc values were found in heavily compacted and red-pigmented sediments inside the impact scar and were comparable to levels found close to slip ways of local boat yards where AF paints from hull stripping and cleaning processes are washed into the sea. The re-distribution of AF contaminated sediments by storms and deposition on nearby reefs constitutes a significant ecological risk that could delay recovery processes and reduce the effectiveness of remediation efforts. Whilst the ecotoxicological effects of AF paint particles interspersed with sediment is unknown, and in need of further study, it is argued that the significance of AF paint contamination of grounding sites has been overlooked.  相似文献   

环境植物样品中铜铅锌铁锰的测定     

马欣  丛玉梅  邵文君 《国土资源》1995,(1)

将环境植物样品在４００─５００℃灰化，用硝酸、氢氟酸和高氯酸分解，用盐酸（１＋１）提取，控制２％─３％的盐酸介质，用火焰原子吸收分光光度法测定环境植物样品中的微量铜、铅、锌、铁、锰。该方法简单、快速、可靠。对环境植物标准样品的测定结果理想。  相似文献   

A shrinking particle—shrinking core model for leaching of a zinc ore containing silica     

Vida Safari  Gilnaz Arzpeyma  Fereshteh Rashchi  Navid Mostoufi   《International Journal of Mineral Processing》2009,93(1):79-83

A new mathematical model was developed for leaching of zinc ores containing silicates such as hemimorphite which produce a gel during leaching with sulfuric acid. This model is based on the shrinking core model in which the particle size and the reacting core shrink simultaneously. It was shown that the actual dissolution time of the ore particles is longer than the time corresponding to the dissolution of chemical zinc oxide itself. It was suggested that because of the existence of silicates in the ore, a gelatinous layer was formed around the reacting core. Since the gel product is soft, it breaks apart when the particles collide and as a result, the particles shrink. However, a thin gelatinous layer always covers the reacting core which increases the mass transfer resistance and increases the leaching time. This model was applied to leaching of a zinc-rich tailing containing hemimorphite and the thickness of the gelatinous layer as well as the diffusion coefficient in this layer was determined.  相似文献   

铅硐山铅锌矿床的氧化富集规律     

张星滨 《矿产与地质》1999,13(1):62-64

铅硐山铅锌矿床氧化带较发育,提出用氧化率来标定矿石的氧化作用特征。从矿区的气候、地形、构造、矿体产状、矿物组成和矿化主岩等对氧化富集作用的影响,总结了铅硐山矿床矿石氧化富集规律。并运用矿石氧化富集规律指导氧化矿开采,取得了较好的经济效益。  相似文献   

Mn-oxides and sequestration of heavy metals in a suburban catchment basin of the Chesapeake Bay watershed     

James P. Adams  Robert Kirst  Lance E. Kearns  Mark P. S. Krekeler 《Environmental Geology》2009,58(6):1269-1280

The Chesapeake Bay is greatly impacted by numerous pollutants including heavy metals and understanding the controls on the distribution of heavy metals in the watershed is critical to mitigation and remediation efforts in controlling this type of pollution. Clasts from a stormwater catchment basin draining a subdivision near George Mason University, Fairfax VA (38°50.090°N 78°19.204°W) were investigated using X-ray diffraction (XRD), Scanning electron microcopy (SEM) and energy dispersive spectroscopy (EDS) to determine the nature of Mn-oxide coatings and relationship to bound heavy metals. Mn-oxides are poorly crystalline and occur as subhedral to anhedral platy particles and more rarely as euhedral plates. Micronodules are a commonly observed texture. Chemical compositions of coatings are variable with average major constituent concentrations being Mn (33.38 wt%), Fe (11.88 wt%), Si (7.33 wt%), Al (5.03 wt%), and Ba (0.90 wt%). Heavy metals are found in the coatings with Zn being most prevalent, occurring in approximately 58% of analyses with an average concentration of (0.66 wt%). Minor amounts of Co, Ni, Pb, and Cl are observed. Heavy metals and Cl are interpreted as being derived from road pollution. Mn-oxides can serve as a sequestration mechanism for pollution but may also release heavy metals. Field and laboratory observations indicate Mn-oxides occurring on the surface of the clasts can be mechanically mobilized. This is a mechanism for transporting heavy metals into the Chesapeake Bay watershed. Deicing agents may serve as a mechanism to release heavy metals through cation exchange and increased ionic strength. This is the first detailed mineralogical investigation of Mn-oxides and the roles they may play in pollution in the Chesapeake Bay.  相似文献   

Spatial and temporal distribution of heavy metal concentrations in mussels (Mytilus edulis) from the Baie des Chaleurs, New Brunswick, Canada     

Fraser M  Surette C  Vaillancourt C 《Marine pollution bulletin》2011,62(6):1345-1351

Previous studies on heavy metal contamination of the Baie des Chaleurs focus only on industrial centers and overlooked the ecosystem as a whole. To fill this gap, the objective of this study is to establish a baseline of the spatio-temporal distribution of heavy metals in mussels from the Baie des Chaleurs based on the ecosystem approach. Our results show, for the first time, a cadmium contamination in mussels across the south coast of the Baie des Chaleurs and not only in industrial centers. Our results also confirm previous studies showing heavy metal contamination of the Belledune area. This study demonstrates that the use of the ecosystemic approach is essential to obtain a comprehensive picture of environmental contamination in marine ecosystems.  相似文献   

Global distributions of Fe,Al, Cu,and Zn contained in Earth's derma layers     

Jason N. Rauch 《Journal of Geochemical Exploration》2011

To improve the usefulness and accuracy of modeling Earth's anthrobiogeochemical metal cycles, global maps at approximately 1° × 1° are produced of the concentrations and masses of Fe, Al, Cu, and Zn contained in continental sediments and soils. The maps generated utilize inverse distance weighting (IDW) and cokriging to generate new estimates for geospatially weighted mean global concentrations for these metallic micronutrients. Sediment metal concentration maps are generated from IDW of sediment samples; global soil maps are produced via cokriging upon an underlying parent rock dataset composed of both surface bedrock and sediment samples. Derived are independent estimates for the global mean concentrations in continental sediments (Fe = 3.1 wt.%, Al = 6.1 wt.%, Cu = 45 μg/g, Zn = 86 μg/g) and soils (Fe = 2.5 wt.%, Al = 3.9 wt.%, Cu = 17 μg/g, Zn = 50 μg/g). While continental sediment concentrations for Cu are within the range of previous estimates, Zn concentrations are relatively higher, ~ 20 μg/g above previous estimates. Fe and Al are slightly depleted (~ 1 wt.%) in continental sediments relative to previous estimates, likely ascribable to sampling bias and error inherent in the comparative methodologies. Besides an estimated global mean, metal concentrations in soils are also broken down by FAO soil group. Metal masses in sediments and soils remain within 30% of previous, non-spatial estimates. These maps also illustrate the discernable spatial variability across the Earth's surface. Despite data gaps, maps of metal mass show regional patterns such as the high quantities of Al in the soils and biomass of the Amazonia and Congo regions. Concentrations of metals are relatively high in the anthrosols of China. Finally, this analysis highlights those areas for which generating and providing publically available geochemical data should be prioritized. For instance, gypsisols, lixisols, and nitisols have little to no analytical data available on metal contents. A sensitivity analysis suggests that the most poorly constrained soil metal concentrations occur in the thick, old tropical soils of central Africa and the anthrosols of eastern China.  相似文献   

广东龙门上仓铅锌矿成矿特征及成矿规律研究          下载免费PDF全文

古志宏 《江苏地质》2011,35(2):130-133

龙门上仓铅锌矿是广东省上仓式沉积改造型铅锌矿的典型矿床。通过对龙门上仓铅锌矿的矿床特征进行研究,综合前人的研究成果,归纳总结出该矿床的成矿要素,并且对矿床的成矿模式进行了初步探讨。研究表明,由大赛坝组构成槽部的开阔向斜以及南西翼帽子峰组层间破碎带构成的控矿构造是该矿的必要成矿要素。矿床成因属于岩浆热液—沉积改造型。  相似文献