Abstract:

In order to study the geochemical characteristics of selenium in surface soil of Qingzhou in Shandong Province, 8,132 surface soil samples were collected with the average density of 5.2 pieces/km² in Qingzhou and the selenium content, organic matter, pH and other indicators were analyzed. The results showed that the selenium content in surface soil ranged from 0.02 to 2.77 mg/kg and the background value was 0.21 mg/kg (n=7,462). The area of selenium-abundant soil in the study area is 140.56 km², accounting for 9.00% of the study area. The area of selenium-sufficient soil is 1,248.39 km², accounting for 79.93% of the study area; the area of potential selenium-deficiency soil is 148.45 km², accounting for 9.50% of the study area; the area of selenium-deficient soil is 24.52 km², accounting for 1.57% of the study area. Selenium in surface soil has different characteristics in different geological units, soil types, landform types and land-use types. Selenium is relatively accumulated in the surface soil with Cambrian-Ordovician parent material, clay soil type, dissolution or moderate-cutting landform type, grassland and woodland land-use type. Correlation analysis showed that there was no correlation between pH and selenium content in surface soil of the study area, but there was a significant positive correlation between organic matter and selenium content.

Key words: geochemical characteristics, selenium, selenium-abundant soil, background value, Qingzhou