Distribution and controlling factors of selenium in weathered soil in Kaiyang County, Southwest China

• Published in: Acta geochimica 2014-09, Vol.33 (3), p.300-309
• Main Authors: Ren, Haili, Yang, Ruidong
• Format: Article
• Language: English
• Subjects: Adsorption; Bedrock; Cambrian; Carbon; Earth and Environmental Science; Earth Sciences; Enrichment; Geochemistry; Leaching; Manganese; Mineralization; Organic carbon; Organic matter; Regional; Selenium; Soil (material); Soil profiles; Soil sciences; Uranium; 中国西南地区; 分配; 土壤剖面; 开阳县; 控制; 早寒武世; 硒富集; 风化
• ISSN: 1000-9426; 2096-0956; 1993-0364; 2365-7499
• DOI: 10.1007/s11631-014-0691-1

Selenium is one of the life-related elements. Survey reveals that selenium enrichment in the studied strata from Kaiyang County is considered to be closely related to the following factors： regional black shale series in Ni- utitang Formation of Early Cambrian, strong adsorption of organic matter （OM）, magmatic hydrothermal migrate along the deep fault, mixing and migration of hydrothermal brine, regional uranium mineralization and presence of a great deal sulfides. For selenium enrichment in its weathered soil and crops, the reason responsible is sele- nium-enriched bedrock, which provides material sources for weathering profile and is considered as the main con- trolling factor of selenium content in the soil profile. After leaching and migrates downwards, organic carbon （OC） adsorption, iron-manganese layer adsorption, geochemical barrier role, selenium content in different profiles, there are mainly three types of distribution features： bottom enrichment type, top enrichment type and no significant en- richment type. Comprehensive analyses find that selenium enrichment area is mainly distributed in the Machang, Gaoyun-Fengsan-Guanpo, Baimadong, Chuandong-Hefeng-Shaoshang and Longgang-Gaozhai region, etc. Besides, around the east part of the county, in Huali and Yongxing selenium are relatively scarce.