Selenium concentration in soil of Iran

摘要

Selenium (Se) plays a key role in the maintenance of normal health in human population. This micronutrient is a crucial nutrient for human health. Se enters the food chain through plants and its concentration in foods is determined by a number of geological and geographical factors. The content of Se in food depends on the Se content of the soil where plants are grown or animals are raised. Since no precise report has been drawn up on Se status for soil and water in different regions of Iran, this research measured soil Se in selected areas of North, South, and Center of Iran (from east to west) for continuing complementary research in the future. Sampling was performed in 51 locations. 17 samples of surface cultivated soil (at depth between 0-20 cm) were collected in each area. Upon preliminary preparation of samples at a research laboratory, the Se rate was measured with ICP-OES Model Varian Vista-MPX. The results of this study demonstrate that some parameters such as rainfall conditions in sampling time, rainfall condition in the days before sampling, the elevation above sea level of sampling points, spraying poison condition, and irrigation methods such as underground water, subterranean, dry farming had significant effects on soil Se rates.