title: Adsorption and desorption behavior of metalaxyl in intensively cultivated acid soils.
abstract: Metalaxyl adsorption and desorption behavior in acid soils were evaluated via batch and stirred-flow chamber experiments. On the basis of batch experiments (adsorption curves of the Giles C-type), metalaxyl has a low affinity for acid soils. Also, as derived from batch and stirred-flow chamber tests, its adsorption in acid soils is dictated mainly by their organic matter and clay contents. The high correlation between these two variables makes it rather complicated to resolve their effects. Metalaxyl adsorption occurs largely (80-99%) via fast adsorption reactions. On the other hand, the pesticide is desorbed in variable proportions (30-100%). The desorption parameters obtained by fitting the results to a pseudo-first-order reaction were correlated with no edaphic variable; however, the q(0)/q(max) ratio, which is a measure of reversibility in the adsorption-desorption process, exhibited significant negative correlation with the organic matter and clay contents.
authors: Departamento de Bioloxía Vexetal e Ciencia do Solo, Universidade de Vigo, Ourense, Spain. alipiobc@uvigo.es
authors: Alipio
authors: A
authors: Bermudez-Couso
authors: David
authors: D
authors: Fernandez-Calvino
authors: Miriam
authors: M
authors: Pateiro-Moure
authors: Beatriz
authors: B
authors: Garrido-Rodriguez
authors: Juan Carlos
authors: JC
authors: Novoa-Munoz
authors: Manuel Arias
authors: MA
authors: Estevez