| In modern society, the landscape water is an important evaluation index for the urban and cultural environment, also increasingly affects people's production, life and health. But for the time being, most of the landscape waters are polluted seriously, the phenomenon of eutrophication is widespread. When external pollution sources are controlled, the polluted landscape water sediment, as the internal pollution sources, constantly releasing pollutant to the overlying water is the major reason to cause the eutrophication. So the key point for the pollution control of eutrophicaton is sediment restoration.In this study, nitrogen pollution controlling on polluted landscape water sediment is the researching object. The main works of this paper are as follows:First, the heterotrophic nitrification bacteria and aerobic denitrifying bacteria are screened from polluted landscape water sediment, and one combination of these bacterias have got by testing nitrogen removal effect; meanwile, one kind of microbial carrier which has good adsorption capacities was chosed by investigating the ammonia adsorption behavior and methylene blue adsorption. And then, in laboratory simulation test, efficiency and controlling conditions of activited barrier with immobilized microorganism to immobilize nitrogen release from sediment was researched. The results show that:(1)A strain of aerobic denitrifying bacteria and a strain of heterotrophic nitrification bacteria were isolated from Yangzhou's canal sediment, named YZX11 and YF10, and the highest ammonia and nitrate nitrogen removal rate by single strain were 77.16% and 87.64%. And three more strains of erobic denitrifying bacteria and heterotrophic nitrification bacteria, named WGX10,WGX15,WGX18 and HF3. HF5. HF7, were isolated from the landscape water sediment of Tang Paradise, and the ammonia and nitrate nitrogen removal rate by single strain were above 50% and 90%.Then these high efficient strains were mixed into 11 different combinations, the highest efficient combination was B (WGX10+WGX15+WGX18+HF 3+HF 5) whose ammonia, nitrate and total nitrogen removal rate stabilized at 100%,62.35% and 65.66%.(2)The maximum of NH4-N and methylene blue adsorption by shale ceramsite were 1.9029mg/g and 3.39mg/g which were 4 and 3 times more than the adsorption capacity by lava. So the shale ceramsite was chosed to be the microbial carrier because of its good adsorption capacity and developed pore structure, on which both pollutants and microorganism can be adsorped.(3)The activitied barrier with biofilm of shale ceramsite can not only efficiently control 60% NH4-N release from sediment, but also stably control 50% total nitrgon release into the overlying water. The nitrous and nitric nitrogen accumulation rate was low. Shale ceramsite was a kind of good microbial carrier, it is easier for the denitrifying bacteria to living and finally reduced the total nitrogen of water released from the sediment; but the control effect of the barrier with shale ceramsite was not obvious.(4)The control effect of the activitied barrier with biofilm of shale ceramsite to immobilize ammonia release from sediment was better when this barrier thickness was 2cm and the DO of the overlying water was 5.0-6.0 mg/L, compared with the condition of 1cm,3cm and DO 3～4mg/L,7～8mg/L. Meanwhile, the aerobic denitrifying bacteria on the activitied barrier exhibited high efficacy and the process of denitrification was carried out completely. Then the effect of the barrier to control nitrate nitrogen release to the overlying water achieved better under such conditions.
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