Distribution of selenium in soils of agricultural fields, western San Joaquin Valley, California

Journal Article · · Soil Science Society of America Journal; (USA)

OSTI ID:5568182

Fujii, R; Deverel, S J; Hatfield, D B ^[1]

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1. Geological Survey, Sacramento, CA (USA)

Soils from three agricultural fields in the Panoche Creek alluvial fan area in the western San Joaquin Valley, California, were analyzed for soluble, adsorbed, and total concentrations of selenium (Se) to assess the distribution and forms of Se in relation to the leaching of Se from soils. This assessment is needed to evaluate the importance of soil Se in affecting ground water concentrations. Soil samples were collected from three fields with drainage systems of different ages (6, 15, 1.5 yr) and different Se concentrations in drain water (58, 430, 3700 {mu}g L{sup {minus}1}, respectively). Concentrations of soluble Se and salinity were highest in soils from the field drained for 1.5 yr and lowest in the field drained for 6 yr. Of the total concentration of soil Se from all three fields, the proportion of adsorbed and soluble Se ranged from 1 to 11% and <1 to 63%, respectively. Most of the soluble Se was present as selenate and most of the adsorbed Se was found to be selenite. Consistent with a model of evaporative concentration of Se and salinity in soils and shallow ground water in this area, most of the variance in soluble Se is explained by salinity (r{sup 2} > 0.68) in saturation extracts of soils sampled from below the water table. In contrast, most soluble salts and Se apparently have been leached from the unsaturated soils in the fields drained for 6 and 15 yr. For the leached soils, dissolution and precipitation of evaporite minerals containing Se may no longer control concentrations of soluble Se.

• OSTI ID: 5568182
• Journal Information: Soil Science Society of America Journal; (USA), Journal Name: Soil Science Society of America Journal; (USA) Vol. 52:5; ISSN SSSJD; ISSN 0361-5995
• Country of Publication: United States
• Language: English

Related Subjects

510200* -- Environment
Terrestrial-- Chemicals Monitoring &amp; Transport-- (-1989)
54 ENVIRONMENTAL SCIENCES
ADSORPTION
CALIFORNIA
CHEMISTRY
CONTAMINATION
DISSOLUTION
ECOLOGICAL CONCENTRATION
ELEMENTS
FEDERAL REGION IX
GEOCHEMISTRY
LEACHING
NORTH AMERICA
SELENIUM
SEMIMETALS
SEPARATION PROCESSES
SOIL CHEMISTRY
SOILS
SORPTION
USA