<b>The influence of organic matter from swine wastewater on the interaction and transport of alachlor in soil</b> - doi: 10.4025/actasciagron.v35i3.16374

Abstract

ABSTRACT. This study evaluated the effects of total and dissolved organic matter produced from two swine wastewater treatment systems, a biodigester and a manure lagoon, on the adsorption, desorption, and leaching of alachlor (2-chloro-N-(2,6-diethylphenyl)-N-(methoxymethyl)acetamide) in soil. It was used the batch equilibrium method to test adsorption and desorption, and the results are presented in Freundlich isotherms. It also used disturbed soil columns to evaluate the miscible displacement of alachlor in soil treated with total and dissolved organic matter. This assay was used to monitor the concentration of alachlor in the leached material, the amount of total organic carbon, and the pH. The addition of swine wastewater promoted greater adsorption and desorption of alachlor compared with the control. The dissolved organic matter promoted less soil adsorption of alachlor compared with the total organic matter and also interacted with the alachlor and/or competed with the exchangeable cation sites in the soil, resulting in greater leaching. The total organic matter contributed to the emergence of new sorption sites in the soil column, and the solids present in the composition may have blocked pesticide passage, resulting in lower loss of alachlor due to leaching.Keywords: adsorption, hydro-dispersive parameters, infrared spectroscopy, leaching, pesticide.Influência da matéria orgânica proveniente de água residuária de suinocultura na interação e transporte do alaclor no solo RESUMO. Este trabalho avaliou o efeito da aplicação de matéria orgânica total e dissolvida proveniente de dois sistemas de tratamento de água residuária de suinocultura, biodigestor e esterqueira, na adsorção, dessorção e lixiviação de alaclor (2-cloro-2,6-dietil-N(metoximetil acetamida)) no solo. O método do equilíbrio foi utilizado para o teste de adsorção e dessorção e os resultados foram apresentados em isotermas de Freundlich. Utilizou-se também colunas de solo deformado para avaliar o deslocamento miscível do alaclor no solo tratado com matéria orgânica total e dissolvida. Este ensaio foi realizado para monitorar a concentração de alaclor no lixiviado, o teor de carbono orgânico total e o pH. A adição de água residuária de suinocultura promoveu maior adsorção e dessorção do alaclor comparado ao controle. A matéria orgânica dissolvida promoveu menor adsorção de alaclor ao solo comparada à total e também interagiu com o alaclor e/ou competiu com os sítios sortivos do solo, resultando em maior lixiviação. A matéria orgânica total contribuiu com o surgimento de novos sítios de sorção na coluna de solo e os sólidos presentes em sua composição podem ter bloqueado a passagem do pesticida, resultando em menores perdas de alaclor por lixiviação.Palavras-chave: adsorção, parâmetros hidrodispersivos, espectroscopia infravermelha, lixiviação, pesticida.

A review of the impact of wastewater on the fate of pesticides in soils: Effect of some soil and solution properties

“…Dal Bosco et al (2013) studied the effect of DOM (1400-1500 mg OC L -1 ) and total OM (TOM) (2150-4800 mg OC L -1 ) derived from two swine WW treatment systems (biodigester and manure lagoon) on alachlor leaching. Disturbed soil columns were prepared with a clayey forest soil.…”

“…In addition, a slight effect on pH, mainly depending on the pH of the soil and that of WW, an increase in electrical conductivity, due to higher ion content in WW, and a higher DOM content in WW, resulted in higher pore velocities (Peña et al, 2011b;Fernández-Gálvez et al, 2012). However, in some cases, a reduction in flow has been reported when WW or DOM solutions are applied and attributed to clogging of the soil pores by salts and solids in solution (Dal Bosco et al, 2013;. Finally, although aggregate stability is affected by WW irrigation, this effect will depend on the type of soil, with especial importance in fine−textured soils (Levy et al, 2014).…”

Sorption and mobility of dimethenamid in a volcanic soil amended with liquid cow manure

“…Moreover, the application of animal amendments also greatly increases the amount of DOM in the soil, modifying the herbicide adsorption process and consequently the volume of leaching. Both increases and decreases of pesticide leaching have been observed (Singh, 2003, Jiang et al, 2008, Song et al, 2008Dal Bosco et al, 2013). A decrease in pesticide adsorption may occur either by DOM-pesticide complexation or by DOM competition with pesticide molecules for soil adsorption sites (Said-Pullicino et al, 2004).…”

Environmental fate and behavior of mesotrione alone and mixed with S-metolachlor and terbuthylazine in Brazilian soils

“…Agricultural and soil management practices have also been reported to affect alachlor sorption-desorption rates (Guo et al, 1993, Locke et al, 1996, Dorado et al, 2005, Dal Bosco et al, 2013 and mineralization (Guo et al, 1991, Liu et al, 2002.…”