玉米秸秆腐解释放溶解性有机质的光谱分析  

Spectral Analysis of Dissolved Organic Matter of Maize Straw in Decomposition Process

作　　者：周向军 齐婷 高茹霞 ZHOU Xiang-jun;QI Ting;GAO Ru-xia(College of Bioengineering and Biotechnology,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：《黑龙江农业科学》2022年第10期76-82,共7页Heilongjiang Agricultural Sciences

基　　金：甘肃省自然科学基金项目“玉米秸秆腐蚀释放溶解性有机质对氟喹诺酮类抗生素的消减作用”(20JR5RA499);天水师范学院项目“秸秆还田溶解性有机质的光谱特性及对黄绵土Pb/Zn赋存形态调控”。

摘　　要：为进一步开展保护性耕作,在模拟农田黄绵土壤微生物条件下,采用总有机碳法研究玉米秸秆不同腐解过程中溶解性有机质的释放特征,通过紫外光谱、红外光谱以及三维荧光光谱法,对溶解性有机质的光谱特性和荧光组分进行解析。结果表明,溶解性有机质在腐解第0.5天达到最大值为221.01 mg·L^(-1),腐解过程可分为腐解初期(0~3 d)、腐解中期(3~30 d)和腐解后期(30~60 d)三个阶段,释放特征呈“W”型趋势。紫外光谱表明,E_(2)/E_(3)和E_(2)/E_(4)均先降低后趋于稳定,SUVA_(254)呈先增加后降低趋势。红外光谱表明,腐解初期主要释放游离氨基酸和可溶性糖,腐解中期以降解蛋白质、淀粉类碳水化合物、脂类等易降解性组分为主,腐解后期则以形成腐殖质类为主。三维荧光光谱表明,溶解性有机质首先转化为类富里酸,随后进一步形成类胡敏酸。研究表明,多光谱联用技术可用于秸秆源溶解性有机质的光谱特性和荧光组分解析。In oder to further develop conservation tillage,the total organic carbon method was used to study the releasing characteristics of DOM in different decomposition processes under simulated microbial conditions of farmland loess.The spectral characteristics and fluorescence components of DOM were analyze d by ultraviolet spectroscopy(UV-vis),infrared spectroscopy(FTIR)and three-dimensional fluorescence spectroscopy(3D-EEM).The results showed that DOM reached the maximum value of 221.01 mg·L^(-1)at 0.5 d,the decompos ition process could be divided into the initial stage of decomposition(0-3 d),the middle stage of decomposition(3-30 d)and later stage of decomposition(30-60 d),showing a“W”shape trend.UV-vis spectra showed that E_(2)/E_(3)and E_(2)/E_(4)both decreased first and then tended to be stable,while SUVA_(254) showed a trend of increasing first and then decreasing.FTIR showed that free amino acids and soluble sugars mainly released in the early stage,protein,starch-like carbohydrates,lipids and other easily degradable components mainly released in the middle stage,humus mainly formed in the later stage.3D-EEM showed that DOM were first converted to fulvic acid-like,followed by further formation of humic acid-like.The research showed that multispectral techniques could be used to analyze the spectral characteristics and fluorescence components of straw-derived DOM.

关 键 词：溶解性有机质 腐解 玉米秸秆 光谱分析 

分 类 号：S141.4[农业科学—肥料学]