title: Effect of size-fractionation dissolved organic matter on the mobility of prometryne in soil.
abstract: Import of organic materials in the form of compost, sludge or plant residues introduces large amounts of dissolved organic matter (DOM) into soils. DOM as a dynamic soil component affects the behaviors of organic pollutants. Different DOM constituents may affect herbicide action in a different way. However, the process of interaction between the distinct DOM-fractions and herbicides is largely unknown. In this study, DOM was separated by size-fractionation into three molecular size groups: MW<3500 Da, 3500 Da<MW<14000 Da, and MW>14000 Da. Effects of DOM-fractions on prometryne sorption/desorption and mobility were analyzed using approaches of batch experiments, soil column and soil thin-layer chromatography. Application of varied DOM-fractions at 50mg DOCL(-1) to the soil reduced the sorption and increased desorption of prometryne. DOM-fraction with MW>14000 Da appeared most effective in prometryne mobilization in the soil than any other fractions. Finally, DOM-fractions were characterized by chemical analyses, fourier transformed infrared spectroscopy (FT-IR) and excitation-emission matrices (EEMs) fluorescence spectroscopy. Our studies revealed that the high-molecular weight fraction contained more aromatic framework and unsaturated structure that was most likely the dominant factor modulating the behavior of prometryne in soils.
authors.affiliation: Department of Applied Chemistry, College of Science, Nanjing Agricultural University, Nanjing, China.
authors.forename: Guang
authors.initials: G
authors.lastname: Chen
authors.forename: Chao
authors.initials: C
authors.lastname: Lin
authors.forename: Liang
authors.initials: L
authors.lastname: Chen
authors.forename: Hong
authors.initials: H
authors.lastname: Yang
mesh_terms: D000327:Adsorption; D002855:Chromatography, Thin Layer; D052918:Environmental Restoration and Remediation; D006540:Herbicides / Q000737:chemistry*; D008970:Molecular Weight; D009930:Organic Chemicals / Q000737:chemistry*; D011400:Prometryne / Q000737:chemistry*; D012987:Soil; D012989:Soil Pollutants / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D006540:Herbicides; D009930:Organic Chemicals; D012987:Soil; D012989:Soil Pollutants; D011400:Prometryne