title: Changes in dissolved organic carbon of soil amendments with aging: effect on pesticide adsorption behavior.
abstract: The effect of aging in the soil of three organic amendments (OAs), one liquid (LF) and two solid ones (SF and AL), has been investigated and related to changes in soil adsorption of metalaxyl and tricyclazole. LF and AL have very high dissolved organic carbon (DOC) contents with low humification index values, whereas SF has a low DOC content but the highest amounts of highly humified material. All OAs increased the adsorption of tricyclazole, whereas adsorption of metalaxyl decreased in soils amended with LF and AL, due to competition with DOC for mineral adsorption sites. With aging, DOC from SF amended soils is not significantly affected and neither is adsorption behavior. On the contrary, the great reduction of DOC from LF and AL with aging has been shown to affect adsorption of metalaxyl and tricyclazole, and this effect is dependent on the pesticide, the nature of the DOC, and the type of soil, in particular its clay mineralogy.
authors.affiliation: Instituto de Recursos Naturales y Agrobiología de Sevilla, CSIC, P.O. Box 1052, 41080 Sevilla, Spain.
authors.forename: Lucia
authors.initials: L
authors.lastname: Cox
authors.forename: M Conceicao
authors.initials: MC
authors.lastname: Fernandes
authors.forename: Adam
authors.initials: A
authors.lastname: Zsolnay
authors.forename: M Carmen
authors.initials: MC
authors.lastname: Hermosín
authors.forename: Juan
authors.initials: J
authors.lastname: Cornejo
mesh_terms: D000327:Adsorption; D000409:Alanine / Q000031:analogs & derivatives* / Q000737:chemistry; D002244:Carbon / Q000737:chemistry*; D004787:Environmental Pollution; D005659:Fungicides, Industrial / Q000737:chemistry; D010575:Pesticides / Q000737:chemistry*; D012987:Soil / Q000032:analysis*; D013050:Spectrometry, Fluorescence; D013844:Thiazoles / Q000737:chemistry; D013997:Time Factors
chemical_list: D005659:Fungicides, Industrial; D010575:Pesticides; D012987:Soil; D013844:Thiazoles; C028175:metalaxyl; D002244:Carbon; D000409:Alanine; C041191:tricyclazole