Premium
Nitrate, Sulfate, and Biphosphate Retention in Acid Forest Soils Affected by Natural Dissolved Organic Carbon
Author(s) -
Kaiser Klaus,
Zech Wolfgang
Publication year - 1996
Publication title -
journal of environmental quality
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.888
H-Index - 171
eISSN - 1537-2537
pISSN - 0047-2425
DOI - 10.2134/jeq1996.00472425002500060022x
Subject(s) - sulfate , soil water , nitrate , dissolved organic carbon , environmental chemistry , chemistry , total organic carbon , carbon fibers , environmental science , natural (archaeology) , soil science , biology , organic chemistry , paleontology , materials science , composite number , composite material
Natural dissolved organic carbon (DOC) may restrict the sorption of inorganic anions in acid forest soils due to the competition for binding sites. Competitive effects of DOC on the sorption of H 2 PO − 4 , SO 2− 4 , and NO − 3 were tested in experiments with intact soil cores taken from different soil types. Solutions were applied containing the inorganic anions at concentrations of 0.06, 0.24, and 0.12 mmol L −1 , respectively, and the concentrations of DOC of the initial solutions varied between 0 and 5.6 mmol L −1 . Most soil horizons showed only a slight decrease of the H 2 PO − 4 sorption as the DOC concentration increased, indicating a higher sorption affinity of H 2 PO − 4 than of DOC. Increase of the DOC concentration resulted in a strong decrease of the binding of SO 2− 4 for all soils investigated. Thus, sorption of SO 2− 4 seems to be weaker than that of DOC. At the highest DOC concentrations, a net release of SO 2− 4 nearly equal to the approximate amount of sorbed carboxyls was noticed for most soils. Thus, DOC may inhibit the sorption of SO 2− 4 to soils completely or even remove SO 2− 4 stored in soils. Because NO − 3 was found not to sorb on soils, no competitive effects of DOC were observed. The results indicate DOC to be a factor controlling the storage and the mobility especially of SO 2− 4 in acid forest soils, whereas its effect on the sorption of phosphate and NO − 3 seems to be less important.