Eficácia do biocarvão no controle da lixiviação do imazapic no solo

Abstract

Agricultural production is commonly associated with the use of pesticides, within this group are herbicides, which are widely used to combat invasive plants that compete for resources such as water and nutrients with the crop, be it soybeans, sugarcane. , cotton, coffee, among others. The sugar and alcohol industries are the second in use of this input, second only to soybean in Brazil. To combat the weed (Cyperus rotundus) weed, Imazapic is one of the herbicides used mainly in sugarcane crop. Studies prove that the Imazapic molecule has high leaching capacity, increasing the risk of transport and contamination of water sources. Organic matter among other benefits has potential for interaction with herbicides, being able to retain the molecule in the soil layer of interest, which for this study was 0-20 cm, where it can enhance the effectiveness in combating invasive plants. Thus, this study aimed to analyze the effectiveness of the addition of biochar to the soil in controlling Imazapic leaching. The biochar was produced from sugarcane bagasse by the slow pyrolysis process in a muffle furnace at a temperature of 300 ºC. The studies were carried out in columns with porous matrix (soil + biochar) in a dystrophic Yellow Argisol (AD). The analysis of the mechanisms involved in the interaction and transport and the determination of hydrodispersive parameters for Imazapic were evaluated by the Convection-Dispersion Model at two Sorption Sites using the CXTFIT 2.0 program. The Kd value was better in the concentration of (0.47 g Kg-1), it was observed that there was a greater interaction between porous matrix and the displaced miscible. Imazapic adsorption was relatively low, even with the increase in organic matter content due to the addition of biochar.