Copper in soils

Ecologically, copper is a trace element essential to many plants and animals. However, high levels of copper in soil can be directly toxic to certain soil microorganisms and can disrupt important microbial processes in soil, such as nitrogen and phosphorus cycling. Copper is typically found in the environment as a solid metal in soils and soil sediment in surface water. There is no evidence that biotransformation processes have a significant bearing on the fate and transport of copper in water. 

Han F.X., Hargreaves J., Kingery W.L., Huggett D.B., Schlenk D.K. Accumulation, distribution and toxicity of copper in soils of catfish pond receiving periodic copper sulfate applications. J Environ Qual 2001b 30 912-919. 

McBride M.B. Forms and distribution of copper in solid and solution phases of soils. In Copper in Soils and Plants, J.F. Loneragan, A.D. Robson, R.D. Graham, eds. Sydney Academic Press, 1981. 

Copper in soils may come from a variety of anthropogenic sources ... 

Thornton, I. 1979. Copper in soils and sediment. Pages 171-216 in J.O. Nriagu (ed.). Copper in the Environment. Part 1 Ecological Cycling. John Wiley, NY. 

Official methods have been published for the determination of nitric-perchloric acid-soluble copper in soil [97] and ethylenediaminetetraacetic acid-soluble copper in soil [98]. The former method involves atomic absorption spectrometric evaluation of the acid digest and the second method involves extraction of the soil with an aqueous solution of ammonium EDTA and atomic absorption spectrometric evaluation of the extract. 

Mesuere et al. [99] and Gerringa et al. [100] have reviewed methods for the determination of copper in soils. Residual copper(II) complexes have been determined in soil by electron spin resonance spectroscopy. Fast neutron activation analysis has been studied [101] as a screening technique for copper and (zinc) in waste soils. Experiments were conducted in a sealed tube neutron generator and a germanium y-ray detector. 

Copper is invariably determined by AAS in a lean air-acetylene flame, using the main resonance line at 324.7 nm. The detection limit is generally around 10 ng ml-1, which is marginally better than that generally achievable by flame AFS, and comparable to that reported for AES using a carefully optimized nitrous oxide-acetylene flame.2 Provided samples are not excessively diluted, this value is adequate for many practical applications in environmental analysis, such as the measurement of plant copper concentration or EDTA- or DTPA-extractable copper in soils. Interferences are rare, and unlikely to be a problem from concomitant elements present in most environmental samples, but matrix matching is still advisable. The sensitivity is inadequate for the direct determination of copper in natural water samples, for which a suitable preconcentration technique must be employed.1,23,24... 

If models are available for predicting the bioavailability of a substance in soils, these can be used to normalize the ecotoxicity data and to derive a normalized SQS related to a certain soil type. Such models have, for example, been developed for nickel and copper in soils. 

Ma Y, Lombi E, Nolan AL, McLaughlin MJ. 2005. Short term natural attenuation of copper in soils effects of time, temperature and soil characteristics. Environ Toxicol Chem 25 652-658. 

James, R.O. and Barrow, N.J., Copper reactions with inorganic components of soils including uptake by oxide and silicate minerals, in Copper in Soils and Plants, Loneragan, J.F., Robson, A.D., and Graham, R.D., Eds., Academic Press, Australia, 1981, p. 47. 

Fig. 1 Graphs showing (a) fractogram and copper concentration in eluent, (b) corresponding size distribution, (c) copper concentration distribution and element ratio distribution of copper in soil sample, and (d) copper per unit surface area distribution.

DTPA - TEA - SOLUBLE COPPER IN SOIL FIGURE 1. The correlations between DPTA-TEA soluble copper contents and enzyme activities of the investigated soils. 

Box 2. Biogeochemical monitoring of copper in soils and crops of agroecosystems of Southern Russia (after Zakrutkin and Shishkina, 1997)... 

Table 2. Content of total copper in soil samples, ppm...

The contents of copper in soils vary significantly (Table 2). 

In general, the background content of copper in soils of southern Russia is less than known geochemical dark values and those for crops are similar with the background numbers (Cabata-Pendias, 1989). 

Meyer A, De La Chevallerie-Haae U and Henze G (1987) Determination of zinc, cadmium, lead and copper in soils and sewage sludges by microprocessor-controlled voltammetry in comparison with atomic absorption spectrometry. Fresenius J Anal Chem 328 565-568. 

Berggren, D., 1992a. Speciation of copper in soil solution from podzols and cambisols of S. Sweden. Water Air Soil Pollut. 62, 111-123. 

Haque, I., Aduayi E. A., and Sibanda, S. (1993). Copper in soils, plants and ruminant animal nutrition with special reference to sub-Saharan Africa. 

Shuman, L.M., 1979. Zinc, manganese and copper in soil fractions. Soil Sci. 127, 10-17. 

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