Plant Production and Protection Division, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow, 226015, India.
Plant Production and Protection Division, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow, 226015, India; Academy of Scientific and Innovative Research (AcSIR), India.
J Environ Manage. 2022 Feb 1;303:114146. doi: 10.1016/j.jenvman.2021.114146. Epub 2021 Nov 24.
The presence of atrazine a persistent herbicide in soil poses a serious threat to the ecosystem. The biochar amendment in soil altered the fate of this herbicide by modifying the soil properties. The present study examines the dissipation and toxicity of atrazine in three contrasting soils (silty clay, sandy loam, and sandy clay) without and with biochar amendment (4%). The experiment was performed for 150 days with three application rates of atrazine (4, 8, and 10 mg kg). The speciation and degradation of atrazine, metabolite content, microbial biomass, and enzymatic activities were evaluated in all treatments. Three kinetic models and soil enzyme index were calculated to scrutinize the degradation of atrazine and its toxicity on soil biota, respectively. The goodness of fit statistical indices suggested that the first-order double exponential decay (FODE) model best described the degradation of atrazine in silty clay soil. However, a single first order with plateau (SFOP) was best fitted for atrazine degradation in sandy loam and sandy clay soils. The half-life of atrazine was higher in sandy clay soil (27-106 day) than silty clay (28-77 day) and sandy loam soil (27-83 day). The variations in the dissipation kinetics and half-life of the atrazine in three soil were associated with atrazine partitioning, availability of mineral content (silica, aluminum, and iron), and soil microbial biomass carbon. Biochar amendment significantly reduced the plateau in the kinetic curve and also reduced the atrazine toxicity on soil microbiota. Overall, biochar was more effective in sandy clay soil for the restoration of soil microbial activities under atrazine stress due to modulation in the pH and more improved soil quality.
莠去津作为一种持久性除草剂存在于土壤中，对生态系统构成严重威胁。土壤中的生物炭改良通过改变土壤性质来改变这种除草剂的命运。本研究在没有和有生物炭改良（4%）的三种不同土壤（粉质粘土、砂壤土和砂质粘土）中研究莠去津的消散和毒性。实验进行了 150 天，莠去津的施用量为 3 种（4、8 和 10mg/kg）。在所有处理中评估了莠去津的形态和降解、代谢物含量、微生物生物量和酶活性。分别使用三种动力学模型和土壤酶指数来研究莠去津的降解及其对土壤生物区系的毒性。拟合优度统计指标表明，一阶双指数衰减（FODE）模型最能描述粉质粘土中莠去津的降解。然而，单一阶加平台（SFOP）最适合描述砂壤土和砂质粘土中莠去津的降解。莠去津的半衰期在砂质粘土土壤中较高（27-106 天），而在粉质粘土（28-77 天）和砂壤土土壤中较低（27-83 天）。莠去津在三种土壤中的消解动力学和半衰期的变化与莠去津的分配、矿物质含量（硅、铝和铁）的可用性以及土壤微生物生物量碳有关。生物炭改良显著降低了动力学曲线的平台，也降低了莠去津对土壤微生物群落的毒性。总的来说，由于 pH 值的调节和土壤质量的改善，生物炭在砂质粘土土壤中对恢复莠去津胁迫下的土壤微生物活性更有效。
