Institute of Plant Nutrition and Resources, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100097, China.
Institute of Plant Nutrition and Resources, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100097, China.
J Environ Sci (China). 2025 Mar;149:139-148. doi: 10.1016/j.jes.2023.10.007. Epub 2023 Oct 14.
The dissolved organic matter (DOM) with high mobility and reactivity plays a crucial role in soil. In this study, the characteristics and phytotoxicity of DOM released from the hydrochars prepared from different feedstocks (cow manure, corn stalk and Myriophyllum aquaticum) under three hydrothermal carbonization (HTC) temperatures (180, 200 and 220°C) were evaluated. The results showed that the hydrochars had high dissolved organic carbon content (20.15 to 37.65 mg/g) and its content showed a gradual reduction as HTC temperature increased. Three fluorescent components including mixed substance of fulvic acid-like and humic acid-like substances (C1, 30.92%-58.32%), UVA humic acid-like substance (C2, 25.27%-29.94%) and protein-like substance (C3, 11.74%-41.92%) were identified in hydrochar DOM by excitation emission matrix spectra coupled with parallel factor analysis. High HTC temperature increased the relative proportion of aromatic substances (C1+C2) and humification degree of hydrochar DOM from cow manure, while it presented adverse effects on the hydrochar DOM from corn stalk and Myriophyllum. aquaticum. The principal component analysis suggested that feedstock type and HTC temperature posed significant effects on the characteristics of hydrochar DOM. Additionally, seed germination test of all hydrochar DOM demonstrated that the root length was reduced by 8.88%-26.43% in contrast with control, and the germination index values were 73.57%-91.12%. These findings provided new insights into the potential environmental effects for hydrochar application in soil.
溶解性有机质（DOM）具有高迁移性和反应活性，在土壤中起着至关重要的作用。本研究评估了在三种水热碳化（HTC）温度（180、200 和 220°C）下，由不同原料（牛粪、玉米秸秆和金鱼藻）制备的水热炭中释放的 DOM 的特征及其植物毒性。结果表明，水热炭具有较高的溶解性有机碳含量（20.15 至 37.65mg/g），且随着 HTC 温度的升高，其含量逐渐降低。通过激发发射矩阵光谱与平行因子分析相结合，在水热炭 DOM 中鉴定出三种荧光组分，包括腐殖酸样和富里酸样物质（C1，30.92%-58.32%）、UVA 腐殖酸样物质（C2，25.27%-29.94%）和蛋白质样物质（C3，11.74%-41.92%）。高 HTC 温度增加了来自牛粪的水热炭 DOM 中芳香物质（C1+C2）的相对比例和腐殖化程度，而对来自玉米秸秆和金鱼藻的水热炭 DOM 则产生了不利影响。主成分分析表明，原料类型和 HTC 温度对水热炭 DOM 的特性具有显著影响。此外，所有水热炭 DOM 的种子发芽试验表明，与对照相比，根长减少了 8.88%-26.43%，发芽指数值为 73.57%-91.12%。这些发现为水热炭在土壤中的应用可能带来的潜在环境影响提供了新的见解。
