Impact of percentage and particle size of sugarcane biochar on the sorption behavior of clomazone in Red Latosol

Abstract

Biochar is a carbonaceous material that has excellent potential as a fertilizer and soil conditioner. However, there is a lack of information concerning the effects of the amount and particle size of this pyrogenic material on the soil sorption capacity. In this work, evaluation was made of changes in clomazone (CMZ) sorption in a Red Latosol following soil conditioning using different percentages (0.25, 0.5, and 1% w/w) of sugarcane biochar in three particle sizes (<106, 106-508, and 508-610 µm). The conditioned soils presented apparent sorption coefficients (K d ) up to 1300 times higher than that of pure soil, besides changes in the behavior of CMZ sorption. The biochar particle size and percentage influenced sorption of the herbicide as well as its retention in the amended soil during desorption processes. Both sorption and desorption Freundlich constants were linearly correlated with the external surface area of the biochar present in the soil.

Effect of the Incorporation of Sugarcane Bagasse Biochar in Leaching and Bioavailability of Clomazone in Soil

“…The CMZ leached on columns filled with authentic soil to the depth of 20 cm. The addition of biochar-amended soil in the first 5 cm of the columns improved the retention of CMZ in this soil layer, 33 and the herbicide was found only in segments up to 10 cm deep in the columns. These results showed us a lower CMZ leaching in treatments with biochar-amended soil compared to columns filled with authentic soil, regardless of the biochar-amended soil mass (or depth) added on the column tops.…”

“…It can be associated with the low sorption of CMZ in soil, which can be explained by its hydrophilic nature and low distribution coefficient (K d = 0.47). 33 Factors as moisture and organic matter content of soil can affect the herbicide retention in the soil colloids. 10 Due to the high affinity of herbicide for soil organic matter, the presence of humic acids with broad aromatic domains, burning residues and biochar in the soil can strongly retain the CMZ, increasing its sorption.…”

Biocarvão Como Atenuante Da Fitotoxicidade De Herbicidas Em Mudas Pré-Brotadas De Cana-Deaçúcar

“…Considerando que não houve diferenças em relação à testemunha para as variáveis altura, clorofila, área foliar e biomassa, com ou sem o biocarvão, algumas diferenças apontadas para alguns tratamentos com efeito positivo do biocarvão pode ser atribuído ao seu efeito orgânico isolado no crescimento da planta associado a efeitos isolados na adsorção dos herbicidas, evidenciando um processo complexo. De acordo com Silva et al (2018) o biocarvão tem potencial para atuar como um fertilizante, com aumento da capacidade de troca de cátions, matéria orgânica e pH, os quais são importantes fatores que afetam os processos de sorção de nutrientes e compostos orgânicos no solo.…”