Selenium in seleniferous environments

Mayland, H.F. and James, L.F. and Panter, K.E. and Sonderegger, J.L. (1989) Selenium in seleniferous environments. SSSAJ Special Publication "Selenium in Agriculture and the Environment". 23:15-50.

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Abstract

Selenium is biologically important because (i) it is essential in animal and possibly
plant metabolism, (ii) in many areas diets do not contain sufficient Se to meet
animals' needs, and (iii) in other areas it is toxic to animals when it occurrs in high
concentrations in soil, water, plants, fly ash, or in aerosols. Animals require 0.05
to 0.1 mg Se/kg in their diets to prevent Se deficiency but suffer Se toxicosis when
dietary levels exceed 5 to 15 mg Se/kg. The earth's crustal materials generally contain
<0.1 mg Se/kg. Higher concentrations are found in Cretaceous shales. The Se-accumulator
plants growing on the seleniferous soils may contain hundreds or even
thousands of mg Se/kg. However, the nonaccumulator grasses and forbs seldom accumulate
>50 mg Se/kg and more often contain <5 mg Se/kg. Soils and plants may
discharge volatile forms of Se into the atmosphere. However, plants may also absorb
measurable amounts of gaseous Se from the atmosphere. Anthropogenic activities
impact the amount of Se entering our nation's lakes, rivers, and the atmosphere.
Combustion of coal and incineration of municipal waste exhaust Se into the environment.
In addition, crop-fallow and irrigation practices that allow leaching waters to
pass through seleniferous strata prior to intersecting with surface flow, augment the
Se levels encountered by plant and animal life.

Item Type:	Article
NWISRL Publication Number:	0676
Subjects:	Mass Import - unclassified
Depositing User:	Dan Stieneke
Date Deposited:	20 Nov 2010 21:53
Last Modified:	05 Jan 2017 18:55
Item ID:	513
URI:	https://eprints.nwisrl.ars.usda.gov/id/eprint/513