蚯蚓对城镇污泥腐殖质的紫外-可见光谱特性的影响

Effects of Earthworms on UV-Vis Spectra Properties of Humus from Municipal Sludge

蚯蚓可加速城镇污泥堆肥腐殖化进程,改变腐殖质及其组分的结构.紫外-可见光谱法可利用紫外-可见光谱参数对腐殖质结构的表征来评价堆肥腐熟度.通过有蚯蚓和无蚯蚓的对比试验,采用紫外-可见光谱法对蚯蚓堆肥过程中可提取态腐殖质(HE)、富里酸(FA)和胡敏酸(HA)的特征吸收参数进行了研究,探讨蚯蚓对其紫外-可见光谱特性的影响.结果显示,蚯蚓对HE和HA中表征芳香族基团含量、苯环取代基种类、木质素类物质含量等紫外-可见特征参数的影响显著;对FA中表征苯环取代基种类、木质素类物质含量的特征参数影响显著.蚯蚓可以明显增强HA中各参数之间的相关性,相较于FA,用HA的紫外-可见光谱特征参数能够从芳构化程度、木质素相对含量、苯环取代基种类、分子缩合度、分子量大小等多方面更加全面的表征蚯蚓堆肥的腐熟程度.

Earthworm could accelerate the humification process of municipal sludge vermicomposting and change the structure of humus and its components.UV-Vis spectroscopy could be used to evaluate the maturity degree through characterizing the humus structure by UV-Vis spectral parameters.In this paper,UV-Vis spectra method was used to study the characteristic absorption parameters of extractable humus(HE),fulvic acid(FA)and humic acid(HA)by a comparative experiment with and without earthworms,and explore the influence of earthworms on UV-Vis spectrum characteristics.The results showed that earthworms had significant influences on UV-Vis parameters used to characterize the content of aromatic groups,the types of benzene ring substituents,the content of lignin in the HE and HA.It also has a significant influence on the characteristic parameters that characterize the types of benzene ring substituents and the content of lignin in FA.Moreover,Earthworms can obviously enhance the correlation among the parameters in HA.Compared with FA,maturity degree of vermicomposting system could be more comprehensively characterized by the aromatization degree,lignin relative content,benzene ring substituent types,molecular condensation degree and the molecular weight size in HA.