Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 10/24/1998
Publication Date: N/A
Technical Abstract: Resin extractors offer a method of extracting a fraction of easily extractable organic matter from soil. Non-ionic resin extractors are effective at extracting a fraction of non-charged, non-polar, small molecules from soil. Interaction or organic constituents with redox sensitive mineral surfaces can also be studied by changing the soil Eh through incubation under anaerobic conditions. Effectiveness of non-charg in extractors is demonstrated with atrazine, metribuzin, and alachlor using XAD-2 resin encased in a dialysis membrane under both aerobic and anaerobic conditions. Anaerobiosis was achieved by incubating soil suspensions with glucose under a 95% N2-5% H2 environment until the redox potential reached -150 mV. Nine soils with a range of physical and chemical characteristics were examined for atrazine, metribuzin, and alachlor content. Amounts of atrazine, metribuzin, and alachlor extracted from soil ranged to 100, 140, 75 ng g**-1, respectively. Resin extraction conducted aerobically recovered about 25% to 50% of the pesticide extractable with conventional solid phase solvent extraction at 60 C (SPE60). Under anaerobic conditions, equal amounts of atrazine were extracted with RE and SPE60. Slightly less metribuzin was recovered under anaerobic extraction with the exception of soils lacking detectable amounts by SPE60. Larger amounts of alachlor were extracted with resins under anaerobic conditions than under aerobic conditions but the amounts were not correlated with those determined by SPE60. Large amounts of soil organic matter were solubilized under anaerobiosis and smaller molecular weight material was extracted with the herbicides. Amounts of co-extracted organic matter varied among soils.