Current agricultural production systems in the U.S. Great Plains integrate crop production with bioenergy generation and animal production.  While these related activities benefit from multiple synergies, they also face significant future environmental challenges related to climate change.  Climate change will impact precipitation intensity leading to variability in infiltration rate which will influence the subsurface mobility of atrazine, a key herbicide in corn fields. In this study, batch and column experiments were carried out to evaluate the influence of soil moisture and infiltration rate on subsurface atrazine fate and transport. Batch degradation experiments were carried out at three soil moisture levels of 5, 15, and 25% for soils collected from a center-pivot irrigated corn production area and the degradation kinetics was evaluated. The column experiments were conducted at three infiltration rates of 64.17, 77.01 and 119.17 mm/d for sandy-loam and two infiltration rates of 64.17 and 91.67 mm/d for loamy soil. Breakthrough data from the column experiments were simulated using one-dimensional contaminant transport modeling. Rapid degradation of atrazine was observed at 15% and 25% moisture content. The column experiments implied that atrazine sorption was higher in loamy soil since retarded transport was observed when compared to sandy loam. It was observed that the transport of atrazine was governed mainly by degradation processes. In addition, simulations were carried out using the one-dimensional contaminant transport model with the field observations and the experimental data obtained as input parameters to evaluate the effects of soil moisture and other climatic drivers on atrazine degradation and transport to groundwater.

Influence of climate change on subsurface atrazine degradation and transport

255th National Meeting (2018)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.