Sorption/desorption behaviour of sulfonylurea herbicides as affected by the addition of fresh and composted olive cake to soil

Abstract

Summary The olive industry generates residues which can be applied as amendments to soils in their original form (olive cake) or after composting or vermicomposting processes. The addition, fresh or incubated, of these amendments to soil and of their different organic fractions was studied in relation to the sorption/desorption of three sulfonylurea herbicides, bensulfuron‐methyl, chlorsulfuron and prosulfuron. Herbicide sorption was low or very low, slightly promoted by the addition of the agricultural by‐products, especially olive cake, and mainly affected by pH of the soil solution, with the organic carbon content having no significant effect on herbicide retention. Desorption was only reduced when fresh olive cake was added. The incubation of soil and amendments for 3 months did not modify herbicide sorption, but made desorption reversible except for olive cake. The transformation of the organic matter of the amendments due to humification and maturity processes are likely to be responsible for this behaviour. Different organic fractions were removed to assess the influence of each fraction on sulfonylurea sorption. Only the removal of all studied organic fractions increased herbicide sorption, revealing the role of humin and mineral fractions in this process. Therefore, the use of organic amendments is not useful for reducing the risk of movement of ionisable molecules in soil.

Direct and residual effects on diuron behaviour and persistence following two-phase olive mill waste addition to soil: Field and laboratory experiments

“…The organic carbon distribution coefficient (K oc ) was calculated from the K d values for a C e value of 10 µM L − 1 , K oc = K d /%OC × 100. Hysteresis coefficients, H, for the sorption-desorption isotherms were calculated, H = [(1/n fa )/(1/n fd )], where 1/n fa and 1/n fd are the Freundlich constants obtained from the sorption and desorption isotherms, respectively Delgado-Moreno and Peña, 2008).…”

Influence of two-phase olive mill waste application to soil on terbuthylazine behaviour and persistence under controlled and field conditions

“…In particular, in Spain, more than 4,000,000 t of organic slurry is generated annually from the continuous centrifuge two-phase process (two-phase olive mill waste, OW), which has to be properly managed to avoid negative environmental impacts. In view of its high organic matter content, one of the alternatives (Roig et al 2006) being considered for recycling this waste material is as an amendment for Mediterranean soils either raw or processed by composting (Delgado-Moreno and Peña 2008), although the addition of composted products is considered a rather expensive option (Dolaptsoglou et al 2007). This strategy could be of special importance for the maintenance of the olive grove ecosystem in which the return of the organic matter to the soil, apart from its positive effect of storing C in the soil, would help to prevent their well-known problems associated with degradation processes (Pleguezuelo et al 2009).…”

Sorption of oxadiazon in soils cultivated in the brazilian cerrado

“…The highest content of organic matter in the soil promotes increased sorption herbicide; therefore, the herbicidal activity decreases with increasing content of soil organic carbon (Ben-Hur et al, 2003). There is an increasing application of agroindustrial wastes rich in organic matter in agricultural soils, due to the low cost or infeasibility of alternatives, such as green manure or animal manure (Delgado-Moreno & Peña, 2008). Strong positive correlation has been reported between the organic carbon content of the soil and the sorption of herbicides (Albarrán et al, 2003;Ahangar et al, 2008), in which leaching of these molecules could be reduced by application of organic compounds.…”

“…Oxadiazon applied in cotyledons of Cucumis sativus promoted disruption of cell membranes after one hour of exposure to light (Duke et al, 1989), rapidly dehydrating and disintegrating the organelles cells.…”

“…Alternatively, test plants (bio-indicator) are used, which exhibit high sensitivity to the herbicide of interest (Eliason et al, 2004;Szmigielski et al, 2009). This technique is more affordable than the chromatographic quantitative methods.…”