小麦秸秆溶解性有机质的光谱学分析  

Spectroscopic Analysis of Dissolved Organic Matter in Wheat Straw

作　　者：周向军 高茹霞 齐婷 ZHOU Xiangjun;GAO Ruxia;QI Ting(College of Bioengineering and Biotechnology,Tianshui Normal University,Tianshui 741001,China;Key Laboratory of Utilization of Agricultural Solid Waste Resources,Tianshui 741001,China)

机构地区：[1]天水师范学院生物工程与技术学院,甘肃天水741001 [2]甘肃省农业固体废弃物资源化利用重点实验室,甘肃天水741001

出　　处：《山西农业科学》2023年第2期157-164,共8页Journal of Shanxi Agricultural Sciences

基　　金：甘肃省自然科学基金项目(20JR5RA499)。

摘　　要：解析小麦秸秆腐解过程中溶解性有机质的释放特征、光谱学特性和荧光组分等信息,对于掌握秸秆还田腐解过程具有重要意义。在模拟农田土壤条件下,通过总有机碳法、紫外光谱法、红外光谱法和三维荧光光谱法,对小麦秸秆溶解性有机质的释放特征、光谱学特性和荧光组分进行分析。结果表明,小麦秸秆溶解性有机质的释放过程基本可分为3个阶段:腐解初期(0~5 d)、腐解中期(5~20 d)和腐解后期(20~60 d),溶解性有机质浓度首先出现短暂波动,随后呈先迅速降低后又逐渐增加的趋势。紫外光谱结果表明,随着小麦秸秆腐解过程的进行,溶解性有机质在270~280、325 nm附近的吸收峰几乎完全消失。红外光谱结果表明,小麦秸秆首先释放亲水性小分子化合物,然后以释放易降解性生物大分子化合物为主,最后释放难降解性生物大分子化合物。三维荧光光谱结果表明,腐解初期以类蛋白、类富里酸、类胡敏酸为主,腐解中期以类蛋白、类胡敏酸为主,腐解后期以类富里酸为主。研究结果表明,光谱学技术可用于分析秸秆源溶解性有机质的腐解过程和荧光组分类型。Analysis of the information such as release characteristics,spectroscopic properties,and fluorescence components of dissolved organic matter(DOM)in wheat straw in decomposition stages is of great significance for grasping the decomposition process of straw returning to field.In this study,under the simulated farmland soil conditions,the release characteristics,spectroscopic properties,and fluorescence components of DOM from wheat straw were analyzed by total organic carbon method,ultraviolet spectroscopy,infrared spectroscopy,and three-dimensional fluorescence spectroscopy.The results showed that the release process of DOM could be basically divided into three stages:early stage(0-5 d),middle stage(5-20 d),and late stage(20-60 d)of decomposition.The content of DOM first fluctuated for a short period,then decreased rapidly and finally increased gradually.Ultraviolet spectrum showed that the absorption peaks of DOM near 270-280 nm and 325 nm almost completely disappeared with the progress of wheat straw decomposition process.Infrared spectrum showed that wheat straw firstly released hydrophilic small molecular compounds,then mainly easily degradable biomacromolecules,and finally refractory biomacromolecules.The three-dimensional fluorescence spectrum showed that protein-like,fulvic acid-like,and humic acidlike acids were the main components in the early stage,protein-like and humin-like acids were the main components in the middle stage,and fulvic acid-like acids was the main components in the late stage.The study showed that spectroscopy technologies could be used to analyze the decomposition process of DOM in straw and its fluorescence components types.

关 键 词：小麦秸秆 溶解性有机质 三维荧光光谱法 红外光谱法 紫外光谱法 

分 类 号：S141.4[农业科学—肥料学]