交通密度对道路雨水径流溶解性有机物污染特性的影响

为了解交通密度对道路雨水径流中溶解性有机物(DOM)特性的影响,采用超滤、荧光激发-发射矩阵光谱、紫外-可见吸收光谱及红外光谱等技术对不同交通密度的道路雨水径流进行表征.结果表明,道路雨水径流中胶体态有机碳(1 k Da)含量高于真溶解态有机碳(1 k Da)含量;道路雨水径流溶解性有机物中类色氨酸蛋白物质含量最多,其次是类富里酸物质和类络氨酸蛋白物质,类腐殖酸物质和微生物代谢物含量较少;主要含有—OH、—COOH、苯环等官能团.道路交通密度并未改变道路雨水径流DOM的种类及官能团组成,但交通密度越大其径流有机污染越严重、胶体态有机碳含量越高、大分子类色氨酸蛋白物质含量越多、芳香性越强.

Impact of traffic density on dissolved organic matter in road stormwater runoff

DOM in road stormwater runoff with different traffic density was characterized by using ultrafiltration membrane separation, three-dimensional fluorescence spectroscopy, UV-Vis absorption spectrum and infrared spectroscopy. The results showed that the content of colloidal organic carbon(>1 kDa) was higher than that of dissolved organic carbon(<1 kDa). Tryptophan-like protein substances were the major constituents, followed by the fulvic-like and tyrosine-like protein substances. Humic-like substances and microbial metabolites were the least constituents of DOM in road stormwater runoff. DOM in road stormwater runoff was mainly consisted of hydroxyl, carboxyl, benzene ring and other functional groups. The traffic density was not the main factor to change the variety and functional groups of DOM in road stormwater runoff. However, we observed that greater traffic density could cause more serious of organic pollution, much higher content of colloidal organic carbon and tryptophan-like protein substances in DOM, and the much stronger of the DOM aromaticity in the road stormwater runoff.