Quantification of fate and retention process of glyphosate in contrasting texture ...
| Grant number: | 16/17683-1 |
| Support type: | Scholarships in Brazil - Post-Doctorate |
| Effective date (Start): | May 01, 2017 |
| Effective date (End): | March 03, 2019 |
| Field of knowledge: | Agronomical Sciences - Agronomy |
| Principal Investigator: | Valdemar Luiz Tornisielo |
| Grantee: | Kassio Ferreira Mendes |
| Home Institution: | Centro de Energia Nuclear na Agricultura (CENA). Universidade de São Paulo (USP). Piracicaba , SP, Brazil |
Abstract The application of biochar to soils has been known for some time to increase herbicide sorption and reduce efficacy. Overall, there is the assumption that increased soil sorption could reduce leaching of herbicides to groundwater, thus improving overall water quality. On the other hand, increased sorption leads to decreased efficacy of soil applied herbicides thereby eliminating the residual action of these chemicals for weed management. However, the sorption potential of hydrochars for herbicides in soil has been rarely investigated. The aim of this study will be to evaluate the effect of amending soils with soybean stover, sugarcane bagasse, and wood chips derived biochars and hydrochar or same raw feedstocks on the sorption-desorption, mineralization, and degradation of mesotrione, diuron, hexazinone, aminocyclopyrachlor, metolachlor, indaziflam, and three indaziflam metabolites (indaziflam-triazinediamine, indaziflam-triazine-indanone, and indaziflam-carboxilic acid). Soil will be amended at 10% (w/w), and sorption-desorption studies will be performed in duplicate using the batch equilibration method. Soils will be treated with 14C-herbicides, and will be incubated for 30 days to mineralization and degradation. Overall, the comparison of the impact of biochar on herbicide sorption is narrow due to the limited number of studies utilizing biochar. Furhermore, the lack of information within these studies to properly characterize the biochar material used further limits the ability to compare results. However, based on the analogous observations with non-biochar materials, the overall conclusions will be that biochar additions will increase sorption, decrease dissipation rates, decrease leaching and movement of the herbicide in the soil, and reduce the bioavailability of the herbicide, which could lead to reduced efficacy. (AU) | |