Fulvic acids (Fas) were isolated from soil (Jiufeng Forest, Beijing) and sediments (Zhushan lake district. Lake Taihu, Jiangsu) according to the method recommended by the International Humic Substances Society (IHSS). The Fas were characterized by elemental analyzer, UV-Vis spectroscopy, three-dimentional fluorescence spectroscopy, FT-IR spectroscopy, and 13C NMR spectroscopy, in order to compare the Fas with that of the IHSS. The results showed that the Fas derived from the soil (Soil FA) and sediment (Sediment FA) had similar elemental composition, ash contents and structure to the IHSS FA, and they had a certain comparability with the IHSS FA. This indicates that the Soil FA and Sediment FA were worthy to be popularly applied as potential standard Fas in China. Further analyses showed that there were some differences in composition and structure among the Fas, due to the various origins and environmental conditions by which Fas come into being. Both the IHSS FA and Sediment FA exhibited a higher content of aromatic carbons than Soil FA, possibly due to the degradation of microorganisms and aquatic plants abundant in the aquatic system. The Fas showed different polarity in the order of Soil FA > Sediment FA > IHSS FA.%参照国际腐殖酸协会(IHSS)推荐的方法,从北京鹫峰森林土壤和太湖竺山湖区表层沉积物中分别提取FA(富里酸)样品.采用元素分析、紫外-可见光谱、三维荧光光谱、傅里叶红外光谱以及13 C NMR分析对FA样品进行了表征,并与IHSS FA进行比较.结果表明:土壤FA和沉积物FA与IHSS FA在元素组成、灰分含量及结构上基本相似,与IHSS FA具有一定的可比性,可以作为我国FA的标准样品.由于FA的来源及其形成环境的不同,各FA之间在组成和结构上存在一定的差异.IHSS FA和沉积物FA的芳香性均略高于土壤FA,这可能是由于水环境系统中含有大量的水生植物以及微生物降解作用所致.3种FA的极性排序为土壤FA>沉积物 FA>IHSS FA.
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