Speciation schemes for soils and sediments

The sequence of operations required to sub-divide the total element content into a series of different fractions is known as a speciation scheme. The distribution data can be collected by 

In view of the number of variables to be considered and the complexity of the overall system, it is not surprising that investigators differ in their approach. The number of published speciation schemes exceeds 12 (Pickering, 1986). The more widely applied systems (and their modified versions) are considered in some detail in Chapters 10 and 11. 

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