Retention of propiconazole and terbutryn on acid sandy-loam soils with different organic matter and Cu concentrations.

Equilibrium propiconazole and terbutryn adsorption characteristics were evaluated in ten acid vineyard soils with a wide range of organic matter and copper concentrations using batch experiments. Adsorption data from equilibrium adsorption experiments were generally well described by linear and Freundlich models. Parameters from these models showed that soil organic matter played a key role of propiconazole adsorption processes, but also the amorphous Fe oxides content in soils.

Phosphorus effect on Zn adsorption-desorption kinetics in acid soils.

The adsorption-desorption kinetics of Zn in the absence and presence of P was studied by using the stirred flow chamber technique. The results thus obtained were compared with those previously obtained for Cu. As with copper, the simultaneous addition of P and Zn in a 1:1 mole ratio to soil was found to significantly increased Zn adsorption relative to the absence of P.

Effect of organic matter and iron oxides on quaternary herbicide sorption-desorption in vineyard-devoted soils.

Herbicide soil/solution distribution coefficients (K(d)) are used in mathematical models to predict the movement of herbicides in soil and groundwater. Herbicides bind to various soil constituents to differing degrees. The universal soil colloid that binds most herbicides is organic matter; however metallic hydrous oxides might also have some influence.

Influence of copper on the adsorption and desorption of paraquat, diquat, and difenzoquat in vineyard acid soils.

Retention of the cationic herbicides paraquat (PQ), diquat (DQ), and difenzoquat (DFQ) in two vineyard soils with a different management history and retention capacity was examined. The influence of copper on the ability of the soils to retain the herbicides was determined by comparing the results of adsorption and desorption tests on untreated and Cu-enriched soil samples, and also on soils that were previously treated with EDTA to extract native copper. The three herbicides were strongly adsorbed by both soils.