堆肥中亲水性有机物还原容量表征及影响因素研究  

Characterization and Investigation of Reduction Capacity of Hydrophilic Organic Matter from Compost and its Influence Factors

作　　者：崔东宇[1,2] 何小松[1,2] 席北斗[1,2] 檀文炳[1,2] 袁英[1,2] 高如泰[1,2] 

机构地区：[1]中国环境科学研究院环境基准与风险评估国家重点实验室,北京100012 [2]中国环境科学研究院地下水与环境系统创新基地,北京100012

出　　处：《分析化学》2015年第2期218-225,共8页Chinese Journal of Analytical Chemistry

基　　金：国家杰出青年科学基金项目(No.51325804);中国博士后科学基金第52批面上项目(No.2012M520349);中央级公益性科研院所基本科研业务专项(No.2012GQ-14)~~

摘　　要：还原容量(RC)是衡量水溶性有机物(DOM)还原特性的重要指标。分别取未腐熟和腐熟后筛分的堆肥样品提取DOM并分离亲水性组分(Hy I)作为电子供体及电子穿梭体,以3种不同形态的铁作电子受体测定其还原容量。结果表明,对于3种形态的电子受体Fe2(SO4)3,Fe(NO3)3和柠檬酸铁(FeCit),腐熟筛分后Hy I的还原容量值分别为15.88,13.41和51.45 mmol e-/mol C,均大于未腐熟阶段的Hy I还原容量值13.45,11.77和43.16 mmol e-/mol C。同时还发现不同电子受体对Hy I的还原能力影响明显,FeCit条件下测得的RC值明显高于在Fe2(SO4)3和Fe(NO3)3条件下的RC值。而且Hy I的微生物还原容量低于本底还原容量。通过紫外-可见光谱特征值(包括SUVA254和SUVA280)、特征值比值(包括A250/A365和A465/A665)及面积积分比值分析发现,芳香族、不饱和共轭双键结构、芳化度和有机质分子量都会对Hy I氧化还原能力产生影响;结合三维荧光光谱体积积分值及百分比分析发现,类腐殖质(包括类富里酸和类胡敏酸)相对含量是Hy I还原容量主要影响因素。本研究为科学表征亲水性组分的氧化还原特性、揭示其在堆肥体系污染物降解转化中的作用提供了科学依据。Reduction capacity （ RC ） is an important index to evaluate the redox ability of dissolved organic matter. In order to determine the RC, hydrophilic organic fractions （ HyI ） isolated from dissolved organic matter extracted from the uncomposted and composted samples were used as electron donators and mediators, and three kinds of irons were chosen as electron acceptors. The results showed that, the RC values from the composted sample were 15. 88, 13. 41 and 51. 45 mmol e -/mol C for the electron acceptors Fe2（SO4）3, Fe（NO3）3 and FeCit, respectively, which were higher than the corresponding values （13. 45, 11. 77 and 43. 16 mmol e-/mol C） from the uncomposted sample. The electron acceptor type shows a dramatic influence on the RC value of HyI. The RC value determined by FeCit was obviously higher than that measured using Fe2（ SO4 ） 3 and Fe（ NO3 ） 3 , and the microbial reducing capacity of the HyI was lower than the corresponding native reducing capacity. By analyzing the special absorbencies （ SUVA254 and SUVA280 ） , absorbance ratios （ A2/A3 and A4/A6 ） and integrated area from UV-vis spectra, it can be found that the RC was affected by aromatic degree, unsaturated conjugated structure, and molecular weight. Excitation-emission matrix spectra coupled with regional integration analysis showed that the relative content of humic-like substances （ humic-like acids and fulvic-like acids） was the main factor influencing the RC value of HyI. The results obtained can be used to characterize the redox properties of HyI, and reveal its role in the transformation and degradation of pollutants during composting.

关 键 词：亲水性组分 还原容量 紫外-可见吸收光谱 三维荧光光谱 

分 类 号：S141.4[农业科学—肥料学]