Effect of Exogenous Carbon on Movement of Simazine and 2,4‐D in Soils

• DOI: 10.2136/sssaj2001.1688
• Publication Date: 2010-07-27T22:53:42Z
• Authors: L. Cox; A. Cecchi; R. Celis; M. C. Hermosín; W. C. Koskinen; J. Cornejo
• Keywords: Simazine; Amendment

Organic amendment (OA) addition is an agricultural practice that can greatly affect pesticide behavior in soil. The influence of three OAs, consisting a liquid (LOA), solid (SOA) humic amendment, and urban waste (SUW), on sorption, persistence, leaching potential simazine (2‐chloro‐4,6‐bis (ethylamino)‐s‐triazine) 2,4‐D (2,4‐dichlorophenoxyacetic acid) sandy soil (P2) has been investigated. OAs were added to P2 at rate 5% (w/w). Sorption was studied using the batch equilibration technique, degradation by incubations 20°C −0.33 kPa moisture content, handpacked columns. Simazine sorption increased order ≤ + LOA < SUW +S OA. herbicide, 2,4‐D, did not sorb soil, but amended soils same as simazine. lower both herbicides compared with SOA attributed higher dissolved organic matter (DOM) content LOA. Simazine's half‐life reduced upon amendment. Degradation followed sigmoidal P2, SOA, SUW, LOA, which persistence much higher. stability 2,4‐D‐dissoved C interactions. Leaching studies indicate affects movement extent than specially case amounts leached are those unamended In greater reduction large‐size conducting pores revealed Hg porosimetry studies, resulted suggested from small differences between