1. Department of Environmental Science & Engineering, Tsinghua University, Beijing 100084, China 2. Research Center for Environmental Engineering & Management, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China
Abstract：Fluorescence fingerprint technique was used to characterize dissolved organic matter (DOM) in river from different sources. The results showed that two types of DOM fluorescence signals were observed in river water: a humic-like fluorescence with three maxima at λex/λem=250/460 nm(A1),220/400 nm(A2) and 325/420 nm(C); and a protein-like fluorescence with two maxima at λex/λem=230/360 nm(T2) and 285/357 nm(T1). The intensity of both of protein-like fluorescence distinctly increased because of the domestic wastewater drainage in the tributary stream. After the tributary converges into the main stream, the Fe3+ concentration in the main stream is 30 times as much as that of tributary stream, and the visible blue-shift of humic-like fluorescence occurred while the others didn’t occur. The intensity of all types of fluorescence decreased from source to estuary resulting from different solute chemistry. However, the intensities of humic-like fluorescence C, A1 and protein-like fluorescence T2 at the longer excitation wavelength decreased significantly because of dilution from main river stream and complexation of humic-like with Fe3+,thus the peaks disappeared at the estuary while the fluorescence peaks at the shorter excitation wavelength were relatively stable on which the river solute chemistry had little effect. Therefore, the fluorophores at the shorter excitation wavelength of 220-230 nm area potential tool to determine the sources of DOM in polluted river.
[1] Lu X Q, Hanna J V, Johnson W D. Applied Geochemistry,2000, 15(7): 1019. [2] Coble P G, Green S A, Blough N V, et al. Nature, 1990, 348(6300): 432. [3] Baker A, Spencer R G M. The Science of the Total Environment,2004, 333(1-3): 217. [4] ZHAO Nan-jing, LIU Wen-qing, LIU Jian-guo, et al(赵南京，刘文清, 刘建国, 等). Spectroscopy and Spectral Analysis(光谱学与光谱分析),2005,25(7): 1077. [5] WANG Zhi-gang, LIU Wen-qing, LI Hong-bin, et al(王志刚, 刘文清, 李宏斌, 等). Acta Scientiae Circumstantiae(环境科学学报),2006,26(2): 275. [6] FU Ping-qing, LIU Cong-qiang, WU Feng-chang(傅平青, 刘丛强, 吴丰昌). Spectroscopy and Spectral Analysis(光谱学与光谱分析),2005,25(12): 2024. [7] ZHAO Nan-jing, LIU Wen-qing, CUI Zhi-cheng, et al(赵南京, 刘文清, 崔志成, 等). Spectroscopy and Spectral Analysis(光谱学与光谱分析),2006,26(5): 922. [8] Donard O F X, Lamotte M, Belin C, et al. Marine Chemistry, 1989,27(1-2): 117. [9] Jaffe R, Boyer J N, Lu X, et al. Marine Chemistry,2004, 84(3-4): 195. [10] Sierra M M D, Donard O F X, Lamotte M, et al. Marine Chemistry, 1994, 47(2): 127. [11] ZHANG Qian-qian, LEI Shu-he, WANG Xiu-lin, et al(张前前, 类淑河, 王修林, 等). Spectroscopy and Spectral Analysis(光谱学与光谱分析),2004,24(10): 1227. [12] Yan Y, Li H, Myrick M L. Applied Spectroscopy,2000, 54(10): 1539. [13] Senesi N. Analytica Chimica Acta, 1990,232: 77. [14] Coble P G, Del Castillo C E, Avril B. Deep-Sea Research Part Ⅱ-Topical Studies in Oceanography, 1998, 45(10-11): 2195. [15] Baker A, Inverarity R. Hydrological Processes,2004, 18(15): 2927. [16] ZHANG Xi-hui, OUYANG Er-ming, L Hong-gang, et al(张锡辉, 欧阳二明，吕洪刚，等). Proceeding of the 4th International Conference on Watershed Management and Urban Water Supply Part B: Urban Water Supply(第4届流域管理和城市供水国际会议论文集B：城市供水),2004, Shenzhen, China: 84. [17] Coble P G. Marine Chemistry, 1996, 51(4): 325.
