Study of processes influencing bioavailability of pesticides in wood-soil systems: Effect of different factors

Abstract

Lignocellulosic wastes and by-products containing lignin are now available in large amounts from forestry and industrial activities, and could be promising organic materials for the biosorption of pesticides by soils in order to reduce point-source pollution. Adding these materials to soil requires understanding the process of pesticide sorption-desorption by wood-soils, as sorption capacity could increase, with changes in pesticide bioavailability and final fate. The objective of this work was to study the effect that pine and oak wood added to soils had on the sorption/desorption of the pesticides linuron, alachlor, and metalaxyl. Experiments were conducted with two sandy loam and sandy clay soils each amended with two wood doses (5% and 50%) after different incubation times (0, 5 and 12 months). A low wood dose (5%) had no significant impact on the sorption (K) of alachlor, but K increased for linuron (up to 5.4-1.7 times) and metalaxyl (up to 4.4 and 8.6 times) in all wood-soil systems. The results were not significantly different after different incubation times. The desorption results indicated that wood decreases the sorption irreversibility of alachlor, and increases that of linuron and metalaxyl, with a varying effect of the wood-soil incubation time. The addition of a high wood dose to soil (50%) was more significant for increasing the sorption of all the pesticides, and the sorbed amounts remaining after desorption (>49% for linuron, >33% for alachlor and >6% for metalaxyl), although there was no apparent discrimination between the two types of woods. The role of the nature of the organic carbón (K values) for sorption was evidenced for alachlor and metalaxyl, but not for linuron. These outcomes are of interest for extending wood application to soil as a barrier for avoiding environmental risk by point-source pollution due to the use and management of pesticides in farming systems.

Simultaneous application of two herbicides and green compost in a field experiment: Implications on soil microbial community

“…In this respect, the application of organic amendments to the soil could act as a barrier to avoid pesticide leaching, minimizing the spread of pollutants (Álvarez-Martín et al, 2016b;Marín-Benito et al, 2017. On the other hand, the use of organic amendments is a common practice in agriculture and in soil remediation processes for increasing the soil content of nutrients and organic carbon (OC) (Clemente et al, 2015;Medina et al, 2012).…”

Amended Vegetation Filters as Nature-Based Solutions for the Treatment of Pharmaceuticals: Infiltration Experiments Coupled to Reactive Transport Modelling

“…Under the experimental pH (8.15 ± 0.20), ketoprofen was dissociated in the anionic form (pKa = 4), and sorption was likely hampered due to electrostatic repulsions both with the negatively charged soil and lignin, considered a crucial substance for the sorption of hydrophobic organic compounds in woodchips [83][84][85]. However, the carboxylate and keto-groups of ketoprofen can form complexes with surface metal species such as aluminum and iron, as well as metal cations like Al 3+ and Fe 3+ [86].…”

Effect of Organic Residues on Pesticide Behavior in Soils: A Review of Laboratory Research

“…The effectivity and rate of application of other organic residues as adsorbents of pesticides has also been reported in different studies. Marín-Benito et al [107] have studied the effect of large amounts of lignocellulosic residues from forestry and industrial activities on the adsorption-desorption of certain pesticides by soils. The study involves two wood wastes (pine and oak wood) at two different doses (5% and 50%) and various incubation times (0, 5 and 12 months) in two soils with different textures (sandy loam and sandy clay).…”