ABSTRACT
This chapter discusses the use of plants and their associated microorganisms to remove Selenium (Se) from polluted soils and water. Decomposing plants also provide soil microorganisms with methyl groups required for Se methylation and serve as a carbon source to stimulate microbial growth. Plants are thought to take up selenate by the same carrier in root cell membranes as sulfate. Numerous microorganisms were shown to be capable of producing volatile Se compounds from soils and sediments, including fungi, bacteria, yeast, and microalgae. Selenium volatilization by plants is strongly influenced by the microbial population in the root zone. Wetland plants remove pollutants through uptake and immobilization in plant tissues. In the case of Se, an additional, and potentially very important, pathway of removal is through biological volatilization. Sediment and plants were the major producers of volatile Se from the system. Micrometeorological flux measurement is another attractive technique for the estimation of the rate of Se volatilization in the field.
