Abstract:

Taishan region is located in the southwest of Pearl River Delta, Guangdong Province. Through different types of rocks，soils and crops were systematically sampled; geochemical characteristic of selenium, source of selenium in soils, and prospects of selenium-enriched agricultural products in this area were studied. The results show that the selenium contents is closely related to lithology and strata, and that content in the Upper Cambrian Shuishi Formation is the highest. The content level of lithology is in the order of epimetamorphic mudstone, argillaceous siltstone, tuff, granite. There are abundant selenium with the surface soil in the area, but distribution of selenium in different parent materials soil profile was significantly different. Selenium in soil profile of epimetamorphic mudstone parent materials was enriched in the bottom, but the sandstone occurred in topsoil layer, while the granite parent materials occurred in the middle illuvial horizon. Magmatism selenium providing, the regional shallow metamorphism activation and enrichment，and clay mineral adsorption cause rich selenium contents in soils in Taishan region. Neither the addition of exogenous selenium nor soil improvement, the selenium contents of corps in the area for more than 40% has reached the requirements for selenium-enriched contents standard of agricultural products, indicating an alluring prospects for the development of seleniumenriched agricultural products.

Key words: selenium, geochemistry, Taishan region, Pearl River Delta