Soil metal profiles

The soil depth profile was sampled 600 m to the Southwest of the Hettstedt metallurgical works from a clayey soil (>35% clay) of the Wipper meadow. Fig. 9-12 shows that the heavy metal emission in the Hettstedt district originated from the copper metallurgical industry [UMWELTBUNDESAMT, 1991]. The heavy metal emission was at a maximum in 1983 and 1985 and is nowadays at a low level because of the closure of most of the emitters. As would be expected from the high values of heavy metal dust emission in recent years, high soil concentrations were found for the elements zinc, copper,... 

One-half of the soil contained in the bin, discussed in point 5 above, was covered with an impermeable metallic insulation cover (west side of bin was covered). This serves as the basic control for the field study. The soil in this half of Bin 5B was protected from rain, wind, and direct sunlight. The soil concentration profile of TCDD, in this half of the bin, was not expected to change with time. The east side of the bin was used as described in point 5 above. 

Metals applied to land are relatively immobile, particularly if the soil has a high pH and high organic content. Many complex physical-chemical processes affect metal mobility in soil. Lead and mercury, which form strong complexes, move very slowly. Zinc, cadmium, and copper move a little faster. Metal profiles in highly contaminated soil penetrate little below the 4-8 inch region even after 60 years. ... 

Similar to most Hg sampling methods, sampling sediments and soils require care in avoiding contamination artifacts due to improper sample handling. However, because Hg concentratiorrs are much higher in soUd matrices than in water, if corrrmonly accepted trace-metal protocols are used, substantial contamination artifacts should be exceedingly rare. Also, because sediment Hg concentration profiles... 

Griffiths B.S., Diaz-Ravina M., Ritz K., McNicol J.W., Ebblewhite N., Baath E. Community DNA hybridization and %G+C profiles of microbial communities from heavy metal polluted soils. FEMS Microbiol. Ecol. 1997 24 103-112. 

ABSTRACT This study forms part of a larger multidisciplinary environmental study of the Lower Guadiana River basin carried out by a joint Portuguese-Spanish research team. It describes the mobility of lead in soil profiles taken over varied lithologies of the Iberian Pyrite Belt and the distribution of this metal with the root, stems and leaves of three plant species native to the area (Cistus ladanifer L., Lavandula luisieri and Thymus vulgaris). Results indicate that at all sample sites the mobility of lead is very low. 

In soils of non-agricultural ecosystems, above ground biomass (foliar uptake) and metal cycling is considered important (see Figure 8), due to large impact on the metal distribution in the humus layer and mineral soil profile. Especially in soils of Forest ecosystems, it may affect the accumulation in the humus layer, which is considered a very relevant compartment regarding the calculation of a critical load. In these soils, however, a steady-state element cycle is assumed, which implies that mineralization, Minj, equals litterfall, Mjf. 

The determination of distribution pattern of various forms of both macroelements and heavy metals in soil profile is a very complicated task. We have to know the... 

We can see that the soluble and exchange forms of these metals are present in small amounts accounting merely for a few percent of the total metal content in soil. The content of organometal species is relatively high in the upper profile rich in humic species, whereas it drops sharply in the mineral horizons. Copper is extensively involved in the biogeochemical cycle in the Forest ecosystems and this is less profound for cobalt. It is noteworthy that a large part of metals (in particular, of copper) become bound to iron hydroxides. This is typical for various trace elements, including arsenic, zinc and other elements with variable valence. 

An earlier study on the speciation of heavy metals and geochemical mapping of the total metal content of the surface soils of Delhi7 showed the total Al content to vary between 1.87 to 5.34% with a mean of 3.57%. In view of the above, the objective of this research was to ascertain primarily the status of Aluminum in Delhi soils by studying its chemical speciation in the soil profile in order to improve the understanding of its distribution in the solid-phase pool of the soil. More precisely, the objectives were ... 

Haidar, A., Profiles and speciation of some heavy metals in Delhi soils, Ph. D. Thesis, Jawaharlal Nehru University, New Delhi, India, 1997. 

Figure 7.5 Profiles of surface-applied metals in acid soil, with and without lime and leached with O.OlMCaCli (McBride, 1994). Reproduced by permission of Oxford University Press...

The soil orientation survey consisted of three east-west traverses across the known areas of mineralization on the property at Pico Prieto and Venado and three soil profiles in the Venado area. The primary purpose of the soil traverses was to determine the spacing required to find a deposit of similar dimensions and style of mineralization, and to determine the optimum soil size fraction and pathfinder elements for these styles of mineralization. The purpose of the soil profile samples was to determine whether metal concentrations vary with soil horizon and depth. 

Evaluation of the soil profile results indicates that there is a strong partitioning of copper and molybdenum into the nearsurface soil horizon. Copper and molybdenum concentrations are significantly greater in the near-surface (0 to 30 cm) B horizon soils than in the deeper C horizon soils (Fig. 1). More work is required to determine the reason for the preferential partitioning of metals into the B horizon. 

Isomorphous substitution of iron oxides is important for several reasons. In the electronics industry, trace amounts (dopants) of elements such as Nb and Ge are incorporated in hematite to improve its semiconductor properties. Dopants are also added to assist the reduction of iron ores. In nature, iron oxides can act as sinks for potentially toxic M", M and M heavy metals. Investigation of the phenomenon of isomorphous substitution has also helped to establish a better understanding of the geochemical and environmental pathways followed by Al and various trace elements. Empirical relationships (e. g. Fe and V) are often found between the Fe oxide content of a weathered soil profile and the levels of various trace elements. Such relationships may indicate similarities in the geochemical behaviour of the elements and, particularly for Al/Fe, reflect the environment in which the oxides have formed (see chap. 16). 

LA-ICP-MS is well suited for monitoring element distribution in annual rings of trees. Annual ring profiles in pine and birch from the Norwegian-Russian border and from northwest Russia measured by LA-ICP-MS as a rapid and sensitive method show the pollution history (especially of the heavy metal content) of the area. No correlation was found between the pollution levels of the soils and the observed metal content in the annual rings by Garbe-Schoenberg et al.20... 

Solely on the basis of volatility profiles, fossil fuel burning is expected preferentially to transfer As, Hg, Cd, Sn, Sb, Pb, Zn, Tl, Ag, and Bi to the atmosphere (1). In a study designed to detect fallout from a major coal burner equipped with a precipitator, Klein and Russell (27) showed that Ag, Cd, Co, Cr, Fe, Hg, Ni, Ti, and Zn were deposited in the surrounding soil (115 sq mi), and with the exception of mercury, enrichment correlated with the respective metal concentrations in the coal. Mercury was more widely disseminated to the environment. Previous work has indicated that mercury exists primarily in the volatile phase of the flue gas and consequently as much as 90% bypasses the electrostatic precipitation control device (2). Bolton and co-workers have evidence that selenium and arsenic may present a similar problem (see Chapter 13). 

By using this model, we find that roughly the same proportion of atmospheric Hg has been transported from the catchments to the various lakes in modern and preindustrial times (26% and 22%, respectively). The balance of the Hg is either volatilized back to the atmosphere or retained by soils in the catchment. Because Hg has a high affinity for soil organic matter, it is not appreciably leached from soils even under acidic conditions, in contrast to other metals (68, 69). However, volatilization to the atmosphere from soils can be significant. In one experiment with undisturbed soil profiles, none of the Hg applied at the surface moved deeper than 20 cm after 19 weeks of irrigation and incubation, although 7-31% of the applied Hg was... 

Silver is one of the basic elements that make up our planet. Silver is rare, but occurs naturally in the environment as a soft, "silver" colored metal. Because silver is an element, there are no man-made sources of silver. People make jewelry, silverware, electronic equipment, and dental fillings with silver in its metallic form. It also occurs in powdery white (silver nitrate and silver chloride) or dark-gray to black compounds (silver sulfide and silver oxide). Silver could be found at hazardous waste sites in the form of these compounds mixed with soil and/or water. Therefore, these silver compounds will be the main topic of this profile. Throughout the profile the various silver compounds will at times be referred to simply as silver. 

Leermakers, M., Y. Gao, C. Gabeille, et al. 2005a. Determination of high resolution pore water profiles of trace metals in sediments of the Rupel River (Belgium) using DET (diffusive equilibrium in thin films) and DGT (diffusive gradients in thin films) techniques. Water Air Soil Pollut. 166 265-286. 

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