同源地人工湖水体和底泥中有机物组成及有机结构的分析研究

Studies on the composition and organic structure of natural organic matter in water and sediment of homologous area in artificial lake

采用XAD-8大孔吸附树脂对水体和底泥中的有机物进行组分分离,并通过傅里叶变换红外光谱(FTIR)、紫外-可见光谱(UV-Vis)和三维荧光光谱(3DEEMs)对自然水体和底泥中的疏水酸(腐殖酸、富里酸)、疏水碱、疏水中性物质和亲水物质进行表征和对比.结果表明,水体中有机物含量:亲水物质>富里酸>腐殖酸>疏水碱>疏水中性物质,底泥中有机物的含量为:腐殖酸>富里酸>亲水物质>疏水碱>疏水中性物质.根据红外、紫外、三维荧光光谱可知底泥中有机物的芳香程度、不饱和程度及分子量大小略高于水体有机物.根据荧光指数(FI)和自生源指标(BIX)可知,底泥和水体的腐殖酸和富里酸主要来源于陆生动植物和土壤有机质,而其余物质主要源于细菌和藻类活动.

Humic acid （ HA）, fulvic acid （FA）, hydrophobie base （ HOB ）, hydmphobic neutral （HON） and hydrophilie substance （HI） in water and sediment were separated with XAD-8 macroporous adsorption resin. Fourier transform infrared spectroscopy （ FTIR）, ultraviolet visible spectroscopy （ UV- Vis） and three-dimensional fluoreseenee spectra（3DEEMs） were employed to characterize and compare the functional groups of those organic matter. The results show that the content of organic matter in the natural water： HI 〉 FA 〉 HA 〉HOB 〉 HON, while the content of organic matter in the sediment： HA〉 FA〉 HI〉 HOB〉 HON. Based on the results of FT-IR, UV and 3DEEMs, it is demonstrated that the ammaticity, unsaturation and molecular weight of organic matter in sediment were slightly higher than those of natural water. The fluorescence index （FI） and autochthonous index （BIX） of 3DEEMs indieated that HA and FA of sediment and water were mainly derived from terrestrial animals ＆plants and soil organie matter, and the rest three speeies were mainly derived from bacteria and algae.