Genesis and management of seleniferous soils in northwestern India

Abstract

The soils capable of producing vegetation with toxic level of selenium (Se) for animal/human consumption are designated as seleniferous soils. In northwestern India, seleniferous soils have developed due to ex situ deposition of Se-rich sediments transported from the nearby Shiwalik hills by ground and surface waters. Considerable mixing of parent materials must have taken place during the process of transportation which leads to variation in Se content of the soils. Among different anthropogenic activities, regular irrigation of crops with Se-contaminated underground water has contributed significantly to Se-enrichment of soil-plant system in this region. The overall productivity potential of seleniferous soils is not different from the normal soils, but the consumption of Se-rich farm produce can lead to serious health hazards in animals and humans. Regular cultivation of Brassicas and poplar has proved as the most suitable mode of reclamation of seleniferous soils via phytoremediation. Recovery of Se and some other chemicals from Se-rich plant biomass should be able to off-set the cost of phytoremediation.