title: Effects of methamidophos and glyphosate on copper sorption-desorption behavior in soils.
abstract: A batch-equilibration technique was employed to study the impact of two organophosphorus pesticides methamidophos (MDP) and glyphosate (GPS) on copper (Cu2+) sorption-desorption for phaeozem and burozem collected from Northeastern China. The addition of the two pesticides decreased Cu2+ sorption, increased Cu2+ desorption and prolonged the equilibrium time of Cu2+ sorption-desorption. But GPS appeared to exert a stronger influence on Cu2+ sorption-desorption due to its stronger complexion with Cu2+. When MDP was added, Cu2+ sorption-desorption was linearly correlated with MDP treatment concentrations. But in the presence of GPS, Cu2+ sorption first underwent a rapid decrease period, and then slowly tended towards a steady period. The reverse pattern could be found for Cu2+ desorption in the presence of GPS. Without pesticides and with the existence of MDP, Cu2+ sorption-desorption kinetics was well conformed to two-constant equation and Elovich equation. But that was not the case for Cu2+ desorption kinetics in the presence of GPS although its sorption could be also described by these two equations.
authors.affiliation: Key Laboratory of Terrestrial Ecological Process, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Yu
authors.forename: Qixing
authors.initials: Q
authors.lastname: Zhou
authors.forename: Zhenli
authors.initials: Z
authors.lastname: He
mesh_terms: D000327:Adsorption; D002412:Cations / Q000737:chemistry; D003300:Copper / Q000737:chemistry*; D005998:Glycine / Q000031:analogs & derivatives* / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D007474:Ion Exchange; D007700:Kinetics; D009946:Organothiophosphorus Compounds / Q000737:chemistry*; D010575:Pesticides / Q000737:chemistry; D012987:Soil / Q000032:analysis*; D013816:Thermodynamics; D000097797:Glyphosate
chemical_list: D002412:Cations; D003300:Copper; D005998:Glycine; D009946:Organothiophosphorus Compounds; D010575:Pesticides; D012987:Soil; D000097797:Glyphosate; C014655:methamidophos