Transport of 14C-prosulfocarb through soil columns under different amendment, herbicide incubation and irrigation regimes

Víctor Barba; Jesús M Marín-Benito; María J Sánchez-Martín; M Sonia Rodríguez-Cruz

doi:10.1016/j.scitotenv.2019.134542

Transport of ¹⁴C-prosulfocarb through soil columns under different amendment, herbicide incubation and irrigation regimes

Sci Total Environ. 2020 Jan 20:701:134542. doi: 10.1016/j.scitotenv.2019.134542. Epub 2019 Oct 23.

Authors

Víctor Barba¹, Jesús M Marín-Benito¹, María J Sánchez-Martín¹, M Sonia Rodríguez-Cruz²

Affiliations

¹ Institute of Natural Resources and Agrobiology of Salamanca (IRNASA-CSIC), Cordel de Merinas 40-52, 37008 Salamanca, Spain.
² Institute of Natural Resources and Agrobiology of Salamanca (IRNASA-CSIC), Cordel de Merinas 40-52, 37008 Salamanca, Spain. Electronic address: msonia.rodriguez@irnasa.csic.es.

PMID: 31734489
DOI: 10.1016/j.scitotenv.2019.134542

Abstract

This study sets out to evaluate the effect on the leaching of prosulfocarb through packed soil columns of applying green compost (GC) as an organic amendment (20% w/w), herbicide ageing over 28 days in the soil (incubation vs. no incubation), and two different irrigation regimes (saturated or saturated-unsaturated flows). Peak concentrations decreased after herbicide incubation in the columns for both unamended (S) and amended (S + GC) soils under both flow regimes. The leached amounts decreased when the herbicide was incubated for 28 days in S (2.1 and 1.9 times) and S + GC (2.9 and 1.6 times), under saturated or saturated-unsaturated flow, respectively. In the S columns, the total amounts retained (43.3%-60.8%) were lower than the ones obtained for the S + GC columns under saturated flow (77.4%-85.2%), suggesting a stronger interaction between the herbicide and the GC-amended soil. This behaviour was not observed under saturated-unsaturated flow, as the total amounts retained were similar in both the S and S + GC columns. Prosulfocarb was primarily retained in the first segment of the S (>28%) and S + GC (>43%) columns under all conditions. Incubation time did not greatly affect the herbicide retention, but it significantly increased the mineralized amount under saturated flow. The total balances of ¹⁴C-prosulfocarb were >73% and >80% in the S and S + GC columns, respectively, indicating that amendment decreased prosulfocarb loss by volatilization. Several factors, such as amendment, herbicide ageing and water flow, proved to be important for controlling the leaching of this herbicide through the soil profile.

Keywords: Ageing; Green compost; Leaching; Prosulfocarb; Soil; Water saturation.