Zhong Xianbao, Yang Yajun, Liu Hexiang, Fang Xianhui, Zhang Yaohui, Cui Ziying, Lv Jialong
College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi Province 712100, PR China; Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China, Ministry of Agriculture, China.
College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi Province 712100, PR China; Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China, Ministry of Agriculture, China.
Sci Total Environ. 2023 Dec 10;903:166274. doi: 10.1016/j.scitotenv.2023.166274. Epub 2023 Aug 13.
This study addresses the research gap in understanding the differences in straw decomposition and variations in humic substances (HS) extracted from various treatment conditions. The aim is to explore the potential of soluble straw HS in remediating heavy metal pollution in soils. The study characterizes straw decomposition structures using scanning electron microscopy (SEM) and X-ray diffraction (XRD), while employing gel permeation chromatography (GPC) and fluorescence spectroscopy (EEM) to analyze the molecular weight and degree of humification of extracted straw HS. The removal efficiency of HS for heavy metals is assessed, with a focus on aerobic humic substances (AE-HS) showing the highest potential for heavy metal removal. Spectral analysis and mass spectrometry analysis reveal the role of phenolic compounds, carboxylic acids, and aromatic compounds in AE-HS, forming humates or complexes to remove heavy metals from contaminated soil. Notably, the optimized AE-HS achieved the highest removal efficiency of 96.18 %, 82.75 %, 60.43 %, and 41.66 % for cadmium, copper, zinc, and lead, respectively. This study provides new insights into the preparation of straw for use as a heavy metal remover and has implications for the use of straw humic substances in soil remediation.
本研究填补了在理解秸秆分解差异以及从各种处理条件下提取的腐殖质（HS）变化方面的研究空白。目的是探索可溶性秸秆HS在修复土壤重金属污染方面的潜力。该研究使用扫描电子显微镜（SEM）和X射线衍射（XRD）对秸秆分解结构进行表征，同时采用凝胶渗透色谱法（GPC）和荧光光谱法（EEM）分析提取的秸秆HS的分子量和腐殖化程度。评估了HS对重金属的去除效率，重点关注需氧腐殖质（AE-HS）显示出最高的重金属去除潜力。光谱分析和质谱分析揭示了酚类化合物、羧酸和芳香族化合物在AE-HS中的作用，它们形成腐殖酸盐或络合物以从受污染土壤中去除重金属。值得注意的是，优化后的AE-HS对镉、铜、锌和铅的去除效率分别达到了96.18%、82.75%、60.43%和41.66%的最高值。本研究为将秸秆用作重金属去除剂的制备提供了新的见解，并对秸秆腐殖质在土壤修复中的应用具有启示意义。
