Department of Soil and Environmental Sciences, National Chung Hsing University, 145 Xingda Rd., Taichung, 402204, Taiwan.
Department of Soil and Environmental Sciences, National Chung Hsing University, 145 Xingda Rd., Taichung, 402204, Taiwan; Innovation and Development Center of Sustainable Agriculture, National Chung Hsing University, 145 Xingda Rd., Taichung, 402204, Taiwan.
J Environ Manage. 2023 Dec 15;348:119316. doi: 10.1016/j.jenvman.2023.119316. Epub 2023 Oct 18.
The accumulation of allelochemicals released by plants is commonly found in continuous monocropping systems. These chemicals, such as phenolic acids, were shown to be the major sources of autotoxin or pathogen accumulation in soils, leading to a direct or indirect continuous cropping obstacle. In this study, three types of agricultural residuals, i.e., rice husk, tea waste, and wood meal, were chosen as feedstocks. Biochar samples were prepared from these feedstocks to examine their abilities to remove gallic acid, a representative phenolic acid. Biochar, which was prepared from wood meal soaked with HPO (1:1.5, w/w) and pyrolyzed at 400 °C (symbolized as WP400), exhibited the highest adsorption capacities of gallic acids and other phenolic acids. The mechanisms of phenolic acid removal by WP400 were evaluated via experimental and spectroscopic investigations to elucidate the notable adsorption capacity of WP400. The adsorption of gallic acids was pH-dependent and followed a pseudo-second-order kinetic model. The combination of high surface area, the existence of O-containing groups, and the enhancement of H bonds between CC groups and phenolic acids may contribute to the high adsorption capacity of WP400. In a pot experiment, we found that celery growth was promoted with the addition of 0.3% (w/w) WP400 to soils that were continuously monocropped with celery. A large decrease in the water-soluble phenolic compound by more than 40% may be responsible for the results. However, WP400 scavenged nitrate, and this study showed that the synergistic actions of WP400 and nutrients exhibited the greatest efficiencies in mitigating the continuous cropping obstacles of celery.
植物释放的化感物质在连续单作系统中普遍存在。这些化学物质，如酚酸，被证明是土壤中自生毒素或病原体积累的主要来源，导致直接或间接的连续种植障碍。在这项研究中，选择了三种农业残余物，即稻壳、茶渣和木粉，作为原料。从这些原料中制备生物炭样品，以考察它们去除代表酚酸的没食子酸的能力。用 HPO（1:1.5，w/w）浸泡的木粉制备的生物炭（符号为 WP400），对没食子酸和其他酚酸的吸附能力最高。通过实验和光谱研究评估 WP400 去除酚酸的机制，以阐明 WP400 具有显著吸附能力的原因。没食子酸的吸附受 pH 值影响，并遵循拟二级动力学模型。高比表面积、含氧基团的存在以及 CC 基团和酚酸之间氢键的增强，可能有助于 WP400 具有高吸附能力。在盆栽试验中，我们发现向连续单作芹菜的土壤中添加 0.3%（w/w）WP400 可促进芹菜生长。水溶性酚类化合物的含量减少了 40%以上，这可能是导致这种结果的原因。然而，WP400 清除了硝酸盐，本研究表明，WP400 和养分的协同作用在缓解芹菜连作障碍方面表现出最大的效率。
