Tebuthiuron leaching in three Brazilian soils as affected by soil pH

• Published in: Environmental earth sciences 2018-03, Vol.77 (5), p.1-12, Article 214
• Main Authors: Faria, Autieres Teixeira, Souza, Matheus Freitas, Rocha de Jesus Passos, Ana Beatriz, da Silva, Antonio Alberto, Silva, Daniel Valadão, Zanuncio, José Cola, Rocha, Paulo Roberto Ribeiro
• Format: Article
• Language: English
• Subjects: Biogeosciences; Bioindicators; Biomonitoring; Capacity; Clay; Clay soils; Climatic conditions; Contamination; Correlation; Cucumis sativus; Dry matter; Earth and Environmental Science; Earth Sciences; Environmental Science and Engineering; Geochemistry; Geology; Herbicides; Hydrology/Water Resources; Indicator organisms; Indicator species; Interactions; Intoxication; Leaching; Liming; Organic matter; Organic soils; Original Article; pH effects; Plants (botany); Soil; Soil characteristics; Soil chemistry; Soil conditions; Soil contamination; Soil organic matter; Soil pH; Soil pollution; Soil water; Soils; Terrestrial Pollution; Water pollution
• ISSN: 1866-6280; 1866-6299
• DOI: 10.1007/s12665-018-7285-x

Underground contamination water by herbicides depends on the interactions between their molecules with physical and chemical soil characteristics and climatic conditions. Studies with columns can estimate the leaching potential of herbicides in soils. This study aimed to determine the effect of soil pH on tebuthiuron leaching, and capacity of bioindicators to detect tebuthiuron residues in three Brazilian soils. Cucumber plants ( Cucumis sativus ) were more negatively affected when grown in soils with lower amounts of organic matter and clay, and in these soils, the tebuthiuron levels reached greater depths in the column. There was a positive correlation between tebuthiuron concentration and cucumber intoxication, and a negative correlation between tebuthiuron concentration and dry matter cucumber in all soils. The tebuthiuron leached up to 50 cm depth even in soils with higher organic matter and clay content. The increasing of soil pH can affect the leaching of nonionic herbicides, and liming practice may elevate the environmental contamination risk by tebuthiuron. The bioindicator method using Cucumis sativus is viable and can be recommended to detect tebuthiuron concentrations above 0.2 mg kg −1 .