Geochemistry and spatial distribution of Se element in soils of typical Se-rich area in Xinmi, Henan Province

Selenium (Se) is an essential trace element for humans and animals.Through the soil quality geochemical investigation and evaluation, it was found that the southern part of Xinmi was rich in selenium resources. Soils (topsoil and subsoil), crops (wheat) and rock samples were systematically collected and analyzed, and the spatial variation, genetic mechanism and biology effect of soil Se were discussed.The analytical data showed that soil total Se contents in southern Xinmi ranged from 0.06 mg/kg to 3.99 mg/kg, with an average of 0.44 mg/kg. According to the evaluation standard of selenium-rich soil in Henan Province, the area of selenium-rich land in the working area is 103.7 km². The analysis of soil profile and soil-forming rock indicates that the soil Se in the study area was mainly derived from soil forming rock, secondary enrichment and anthropogenic source. The Se-enriched ratio of wheat samples was 52.94% according to national standards.