The Effects of Organic Matter on Ammonium Adsorption in Wuli Lake Sediments

Organic matter (OM) is important for ammonium sorption in lake sediments, but as a matter of fact, there is no general consensus about the effects of OM on ammonium adsorption behavior. In this study, the sediment samples of different OM contents and the different components of organic matter were gained from Wuli Lake sediment through pretreatment, then the ammonium adsorption kinetics and thermodynamics processes were investigated without taking the mineralization of OM into account in simulating laboratory condition, especially analyzing the ammonium adsorption mechanism and adsorption contribution of the different component of OM using scan electronic microscope (SEM)techniques. The results show that the ammonium adsorption on sediments was effected by the OM content and the humified degree of OM simultaneously, The different components of OM had different surface characteristics, and the order of ammonium adsorption capacity was HA>HKB>KB>BC;Controlled by the humified degree of OM, the accessibly young OM (HA) rather than the total OM was a factor in the adsorption of ammonium.