Toward conditions favourable to mobility of trace elements in soils.

Ary Bruand (1)

1 ISTO - Institut des Sciences de la Terre d'Orléans

The mobility of trace elements in soils is often discussed because of consequences for their bioavailability and thus their potential ecological toxicity. Numerous studies showed that oxides and oxi-hydroxides could be an important sink for trace elements [1,2]. In many soils, trace elements tend to accumulate in oxides and oxi-hydroxides that act as scavengers [7,9,10]. Indeed, as a recent example, extraction for As speciation in contaminated soils showed that As originating from irrigation was partly retained by Feoxi- hydroxides [3]. Other experiments also showed that adding Fe-bearing compounds to contaminated soils reduces As mobility, but increases Pb and Cd mobility [8], thus indicating that further investigations are required to elucidate trace-element mobility in soils. However, soil oxides and oxi-hydroxides play a significant role in controlling trace element mobility and new conditions leading to dissolution of oxides and oxi-hydroxides should be carefully considered.

Domains: Continental interfaces, environment

Ary Bruand. Toward conditions favourable to mobility of trace elements in soils.. Comptes Rendus Géoscience, 2005, 337, pp.549-550. ⟨10.1016/j.crte.2005.02.004⟩. ⟨hal-00023345⟩