Js. Rieuwerts et al., FACTORS INFLUENCING METAL BIOAVAILABILITY IN SOILS - PRELIMINARY INVESTIGATIONS FOR THE DEVELOPMENT OF A CRITICAL LOADS APPROACH FOR METALS, Chemical speciation and bioavailability, 10(2), 1998, pp. 61-75
The concept of critical loads, previously applied to acidifying substa
nces, is currently being extended, within the Convention on Long Range
Transboundary Air Pollution (CLRTAP), to several metals: Cd? Cu, Hg,
Pb and Zn. Receptors in the soil, such as plants and microbiota, are d
irectly exposed to these metals via the soil solution and this should
ideally be reflected in environmental quality objectives which, presen
tly, are commonly based on 'total' rather than bioavailable metal cont
ents of soils. An understanding of the factors influencing the partiti
on of metals between the solid and solution phases of soils is an esse
ntial prerequisite of any attempt to apply the critical loads approach
in a manner which relates to the effects of metals on soil organisms.