We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Determination of extractable and non-extractable radioactivity from prairie soils treated with carboxyl- and ring-labelled [<sup>14</sup>C]2,4-D.
- Authors
Smith, Allan E.; Muir, Derek C. G.
- Abstract
Ring-and carboxyl-labelled [14C]2,4-D were incubated under laboratory conditions, at the 2 µg/g level, in a heavy clay, sandy loam, and clay loam at 85% of field capacity and 20 ± 1°C. The soils were extracted at regular intervals for 35 days with aqaeous acidic acetonitrile, and analysed for [14C]2,4-D and possible radioactive degradation products. Following solvent extraction, a portion of the soil residues were combusted in oxygen to determine unextracted radioactivity as [14C]carbon dioxide. The remaining soil residues were then treated with aqueous sodium hydroxide, and the radioactivity associated with the fulvic and humic soil components determined. In all soils there was a rapid decrease in the amounts of extractable radioacitivity, with only 5% of that applied being recoverable after 35 days. All recoverable radioactivity was attributable to [14C]2,4-D, and no [14C]-containing degradation products were observed. This loss of extractable radioactivity was accompanied by an increase in non-extractable radio-activity. Approximately 15% of the applied radioactivity, derived from carboxyl-labelled [14C]2,4-D, and 30% from the ring-labelled [14C]2,4-D was associated with the soil in a non-extractable form, after 35 days of incubation. After 35 days, less than 5% of the radioactivity from the carboxyl-labelled herbicide, and less than 10% of the ring-labelled material, was associated with the fulvic components derived from the three soils. Less than 5% of the applied radioactivities were identifiable with any of the humic acid components. It was considered that during the incubation [14C]2,4-D did not become bound or conjugated to soil components, and that non-extractable radioactivity associated with the three soil types resulted from incorporation of radioactive degradation products, such as [14,C]carbon dioxide, into soil organic matter.
- Subjects
SOIL testing; ACETONITRILE; SOLVENT extraction; SOIL classification; CARBON dioxide; FULVIC acids
- Publication
Weed Research, 1980, Vol 20, Issue 2, p123
- ISSN
0043-1737
- Publication type
Article
- DOI
10.1111/j.1365-3180.1980.tb00055.x