[Effect of Carbon and Nitrogen Forms on Decomposition of Organic Matter in Sediments from Urban Polluted River].

To reveal the controlling mechanism of urban polluted river,four trophic level urban river was studied. The change of distribution of organic matter and nitrogen in the sediment was studied while the organic matter was disposed. High level of organic matter is the significant feature of urban city rivers. the humin (HM) was the major fraction of humus, accounting for more than 65% of OM. The most proportion of the total nitrogen (TN) was organic nitrogen which accounted for more than 50%. The amount of organic matter removal increased after the sediment adsorbed the saturated ammonia, which suggested ammonia as the main limited factor for the decomposition of organic matter. The most of Ammonia was adsorbed onto unstable humins. The HM was more stable than other organic matter which was disposed by Hydrogen peroxide (HO).