Autoria: MANTOVANI, E. C.; SCORZA JUNIOR, R. P.; FOLONI, L. L.

Resumo: This work had the aim to study the leaching of the herbicide picloram in field conditions using a drainage lysimeter under Brachiaria decumbens vegetation and also to test the MACRO model to simulate the leaching of this herbicide. The experiment was carried out in the experimental area of the Agricultural Engineering Faculty in the State University of Campinas, in Campinas, São Paulo State, Brazil. The modified drainage lysimeter had 2 m diameter and 3m depth. Soil solution samples were collected in 10 points of 30-cm depth intervals using PVC tubes and were always collected one day after rainfall between October 2006 and March 2007. Quantification of picloram was done using gas chromatography linked to mass spectrometry. Sorption coefficient and degradation rate coefficient at 20°C were also obtained in laboratory. Results have shown that about 455 µg L-1 of picloram leached to 30 cm depth after 11 days of application. Picloram did not leach to below 30 cm depth. MACRO model did simulate the concentration peak of picloram after 11 days of application but overall simulated concentrations were underestimated.

Ano de publicação: 2008

Tipo de publicação: Artigo em anais e proceedings

Unidade: Embrapa Agropecuária Oeste

Palavras-chave: Brasil, Irrigação, Lisímetro, Solo