Sorption and desorption of selenium in different soils of the mediterranean area

The microbial impact on the sorption behaviour of selenite in an acidic, nutrient-poor boreal bog

“…In the environment selenium occurs with different oxidation states forming selenide (Se 2À ), elemental Se (Se 0 ), selenite (SeO 3 2À ), selenate (SeO 4 2À ), and organic Se (Kausch et al, 2012;Pezzarossa et al, 1999). At high redox potential selenate dominates and at intermediate redox conditions selenite becomes more prevailing (Nakamaru and Altansuvd, 2014;Pezzarossa et al, 1999).…”

“…At high redox potential selenate dominates and at intermediate redox conditions selenite becomes more prevailing (Nakamaru and Altansuvd, 2014;Pezzarossa et al, 1999). Se 2À and Se 0 are found typically in most reducing environments with low pH (Nakamaru and Altansuvd, 2014;Pezzarossa et al, 1999). Under non-flooded conditions (mineral soils) the solubility of selenium is affected by adsorption on oxy-hydroxides of aluminium (Al), iron (Fe) and manganese (Mn), but in wetland environments, such as acidic bogs, reduced selenium (Se 0 ) and organic matter bound Se (Se-org) are the most important forms (Nakamaru and Altansuvd, 2014).…”

Sorption of selenium(VI) onto anatase: Macroscopic and microscopic characterization

“…According to Combs et al (1996) and Schlekat et al (2000), elemental selenium has little toxicological impact to most organisms. Metal selenides and elemental selenium, insoluble and found in reducing environments, are unavailable to plants and animals (Elrashidi et al, 1987;Pezzarossa et al, 1999).…”

Uncommon heavy metals, metalloids and their plant toxicity: a review

“…Some studies demonstrated that selenate (SeO 4 2-) is the predominant Se form in neutral pH soils and represent the most available Se from plants (Gissel-Nielsen et al 1984). Under redox conditions and lower pH-presence of organic acids-selenate can be converted to selenite (SeO 3 2-) that is less available and mobile, because of its binding onto the surface of soil particles depending on the soil type (Balistrieri and Chao 1987;Johnsson 1991;Neal et al 1987;Pezzarossa et al 1999;Spackman et al 1994). pH 5.3 proved to be most suitable for Se utilization in field experiments, but then pH 5.2 and 5.9 demonstrate the lowest Se utilization, but very important factor for Se uptake is soil type.…”