河流底泥中溶解性有机物的释放途径及影响因素研究

以沈阳市新开河底泥为研究对象，考察了河流底泥中溶解性有机物（DOM）的释放途径，并分析了时间、温度、pH值、底泥粒径、盐度和上覆水体中溶解性有机碳（DOC）浓度对河流底泥DOM释放的影响.此外，还研究了底泥释放对上覆水体中DOM的光谱学特性的影响.结果表明，对底泥DOM释放影响程度最高的是间隙水的混合作用，其次是底泥表层静态释放，而悬浮颗粒释放对底泥DOM释放的影响程度较小.底泥DOM的释放量随温度，pH值，底泥粒径，盐度的增大而增大.上覆水体DOC浓度较高时，DOM由上覆水体向底泥迁移.扰动作用能够影响底泥DOM的迁移.类富里酸荧光物质和类芳香族蛋白质荧光物质是底泥DOM中的主要荧光物质.河流底泥DOM向上覆水体释放的主要是激发波长分别为280~300nm和320~380nm的荧光物质.并且，扰动作用促进了荧光物质由底泥向上覆水体的释放.

Release pathway and influencing factors of dissolved organic matter in river sediments

The release pathway of dissolved organic matter (DOM) in sediments of the Xinkaihe River in Shenyang, as well as the effect of time, temperature, pH, sediment particle size, salinity, and dissolved organic carbon (DOC) concentration in the overlying water on the release of DOM in sediments was evaluated. In addition, the effect of release of DOM in sediments on the spectroscopy characteristics of DOM in the overlying water was also examined. The results showed that the mixing action of interstitial water had the greatest influence on the release of DOM in sediments, which was followed by the static release of surface sediment, while the release of suspended particles made slight influence on the release of DOM in sediments. The release amount of DOM in sediments increased with the increase of temperature, pH, sediment particle size, and the salinity. When the DOC concentration in the overlying water was relatively high, the DOM moved from the overlying water to the sediment. The disturbance could affect the migration of DOM in sediments. The fulvic acid- and aromatic protein-like fluorophores were dominant in fluorescent materials in DOM in sediments. The fluorescent materials with excitation wavelength of 280~300nm and 320~380nm were the main fluorescent materials which were released from the sediment to the overlying water. Moreover, the disturbance promoted the release of fluorescent materials from the sediment to the overlying water.