Trace element distribution in arid zone soils

TRACE ELEMENT DISTRIBUTION IN ARID ZONE SOILS 

The primary sources of trace elements in soils are the parent materials from which soils are derived. These parent materials constitute the reserve for trace elements. Concentrations of trace elements in soils are directly dependent upon their abundance in the earth crust. In general, concentrations of most trace elements in global soils are from one third to three times those in the earth s crust. The logarithm ratios of their concentrations in the global soils over the earth s crust are in the range 0.5 (Fig. 2.2). 

This is especially important for trace elements in soils in undeveloped arid and semi-arid zones. In agricultural ecosystems, two more 

Trace elements can be transported out of arid soils through plant biomass removal and erosion/leaching. Plant biomass removal is through production of food, feedstuff, and fiber plants. Wind erosion is a serious loss of surface soils and trace element outputs from arid and semi-arid soils as discussed in the first chapter. 

2 TRACE ELEMENTS IN SOILS AND ROCKS A GLOBAL VIEW 

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