Metal atmospheric deposition

Nash, T. H., Gries, C., Zschau, T. et al. (2003). Historical patterns of metal atmospheric deposition to the epilithic lichen Xanthoparmelia in Maricopa County, Arizona, USA. Journal de Physique IV, 107, 921. ... 

HEAVY METALS ATMOSPHERIC DEPOSITION AROUND A MUNICIPAL INCINERATOR PLANT IN BELGIUM... 

Adrianno 1986). The zinc concentration can be much higher in the vicinity of ore deposits and smelters (Burkitt etal. 1972). Like other metals, atmospheric deposition has increased zinc concentrations in surface soil from the 19th century to the present day, but the exact deposition rates cannot be reconstructed, because zinc is rather mobile at the usual pH levels (Gallo vay... 

Atmospheric Deposition of Heavy Metals and Forest Health. Smith, W.H. Virginia Polytechnic Institute Blaclsburg, VA, 1989. 

All the factors mentioned in the previous sections play a role in the movement of metals through their overall biogeochemical cycle injection into the atmosphere, deposition onto land or water surfaces, transport via rivers and... 

The receptors of interest are soils of agricultural (arable lands, grasslands) and non-agricultural (forests, steppes, heath lands, savanna, etc.) ecosystems. In non-agricultural ecosystems, the atmospheric deposition is the only input of heavy metals. Regarding the Forest ecosystems, a distinction should at least be made between Coniferous and Deciduous Forest ecosystems. When detailed information on the areal distribution of various tree species (e.g., pine, fir, spruce, oak, beech and birch) is available, this should be used since tree species influence the deposition and uptake of heavy metals and the precipitation excess. On a world scale, soil types can be best distinguished on the basis of the FAO-UNESCO Soil Map of the World, climate and ecosystem data from NASA database (1989). 

We can see that the content of trace metals in water extraction is very low. This means that the direct involvement of these metals in biogeochemical cycles is very restricted. The significant increase of metal contents in acid-soluble form was shown only for Fe, Mn and, partly, for Zn. These data testify the importance of atmospheric deposition for the Arctic ecosystems as a source of nutrients. 

Table 11. The concentration of trace metals in atmospheric deposition and ground waters of Siberian Taiga Forest ecosystems, pg/L (after Shvarlsev, 1978 Dobrovolsky, 1994).

Annual emissions of heavy metals from the anthropogenic sources of HELCOM countries significantly decreased during the period of 1990-2001. In particular, annual emissions of cadmium decreased by 45%, whereas lead and mercury emissions reduced by 60%. Following this reduction and also due to the changes of heavy metals emissions in other European countries the level of atmospheric depositions to the Baltic Sea has also significantly decreased (Figure 20). Compared to 1990... 

Driscoll et al. (1994) have studied the mercury species relationships among water, sediments, and fish (yellow perch) in a series of Adirondack lakes in New York state, USA. In most lakes, approximately 10% of the total mercury loading was in the form of C2HsHg+. Mercury concentrations increased as pH fell, but the best correlation was found between [dissolved Al] and [dissolved Hg] suggesting that the same factors are responsible for mobilizing both these metals. Methylmercury concentrations correlated strongly with the dissolved organic carbon content in the water. Fish muscle tissue was analyzed for mercury and showed an increase with age. However, the study was unable to resolve the question of whether the principal source of mercury to these lakes was atmospheric deposition or dissolution from bedrock due to acid rains. 

Trace metals (arsenic, cadmium, chromium, copper, nickel, lead, mercury, zinc) Industrial and municipal wastewaters runoff from urban areas and landfill erosion of contaminated soils and sediments atmospheric deposition Toxic effects including birth defects, reproductive failure, cancer, and systemic poisoning. 

Cole KL, Engstrom DR, Futyma RP, et al. 1990. Past atmospheric deposition of metals in northern Indiana measured in a peat core from Cowles Bog. Environmental Science and Technology 24 543-549. 

Taylor GJ, Crowder AA. 1983. Accumulation of atmospherically deposited metals in wetland boils of Sudbury, Ontario. Water Air Soil Pollut 19 29-42. 

Storm water runoff from cities and villages presents another problem. This runoff contains salts from road deicing, street refuse, animal waste, food litter, residue from atmospheric deposition of sulfuric and nitric acid, metals, asbestos from automobile brakes, rubber from tires, hydrocarbons from motor vehicle exhaust condensates, oil and grease, soil and inorganic nutrients from construction sites, and a variety of other chemicals. Research shows a heavy impact of urban nonpoint pollution on freshwater quality (World Resources Institute, 1988). 

These reactions are unlike any we have encountered so far. They are heterogeneous reactions, which means that the reacting system consists of two or more phases. Usually, the metal catalyst is present as a finely divided solid suspension in the liquid or solution to be reduced. Alternatively, the metal is deposited on an inert solid support such as carbon, barium sulfate, alumina (A1203), or calcium carbonate. Then the mixture of the liquid substrate and solid catalyst is shaken or stirred in a hydrogen atmosphere. However, the actual reaction takes place at the surface of the metal catalyst and is an example of heterogeneous or surface catalysis. 

Mijic Z, Stojic A, Perisic M, Rajsic S, Tasic M, Radenkovic M, Joksic J (2010) Seasonal variability and source apportionment of metals in the atmospheric deposition in Belgrade. Atmos Environ 44(30) 3630-3637... 

Sweet, C.W., Weiss, A. and Vermette, S.J. (1998) Atmospheric deposition of trace metals at three sites near the Great Lakes. Water Air and Soil Pollution, 103(1-4), 423-39. 

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