Land Resources - Case study

Selenium: Punjab

In 1981-82, farmers from Hoshirapur and. Nawanshehar Districts approached the scientists in the Punjab Agricultural University (PAU), Ludhiana, as their wheat crops had turned white. Soil analysis indicated selenium (Se) levels in the area were above toxic limits. Se is a naturally occurring trace element, essential for animal and human health, but the gap between the requirement and excess is narrow. Soils containing 0.5 ug of Se per kg or more are injurious to health. In some areas of Punjab, Se levels range from 0.31 ug/kg to 4.55 ug/kg. Rice cultivation requires the presence of standing water. Being highly soluble, Se dissolves and comes to the surface; the water then evaporates leaving the Se behind.