| Since Three Gorges Reservoir was impounded, the problem of aquatic environment security began to spring up, water pollution control is very ursent, which calls for newly builting municipal wastewater treatment plant. There are about 1447 urbans sprawling in storage area, which is of bad economic level, and the management level isunenlightened. A innovative, low energy consumption and management wastewater treatment technology is highly needed. Constructed wetland is such one. It is of low investment, low operation cost, low demands of the administration, less surplus sludge production. In accordance with future the towns, especially the geographic and economic and climatic condition in storage area, two kinds of constructed wetland systems (horizontal subsurface flow constructed wetland system and vertical flow constructed wetland system) are designed in this article and have been carried on the primary experiments. The test included design and startup of reactor, under normal temperature researching the relatship between treatment effect and operation character and relative parameter that useing the constructed wetland treatment the municipal wastewater. Researched on horizontal subsurface flow constructed wetland, vertical flow constructed wetland and subsurface-vertical flow constructed wetland, the conclusions are as follow: 1)Under the condition of 14.36 ℃~24.21 ℃and acclimatization plants, startup constructed wetland system by flowing into municipal sewage is feasible During the startup process, accelerated startup process is feasible in the way of steeping down the hydraulic restate time (HRT) to bring up organic volume load, further to promote micro-organism growth and reproduction. 2) The hydraclic delay time (HRT) is a mian factor witch effects the result of treatment. Commonly, the treatment result of constructed wetland get better as the HRT become longer. 3)The subsurface flow wetland has good CODCr removal capacity, the removal rate of CODCr ,TP and TN is 71%,41.2% and 34.34%, the concentration of CODCr ,TP and TN is 89.6 mg/L,1.74 mg/L and 22.13 mg/L in condition of HRT is 36 hours. 4) The CODCr removal of vertical constructed wetland is lower than subsurface constructed werland, but its TP and TN removal capacity exceed. The removal rate of CODCr ,TP and TN is 69%,44.96% and 37.33%, the concentration of CODCr ,TP and TN is 92 mg/L, 1.63 mg/L and 21.12 mg/L in condition of HRT is 36 hours. 5)The vertical flow-subsurface flow combination constructed wetland (we call combination constructed wetland in the next) has good removal capacity of CODCr ,TP and TN. In condition of HRT is 36 hours, its removal rate of CODCr ,TP and TN reachs 71%,41.2% and 34.34%, accordingly the concentration is 46 mg/L, 1.29 mg/L and 20.32 mg/L. 6) The three systems are efficient in removal of Suspended Solid (SS), when the hydraulic restate time is 36hour, the removal rate of SS can beyound 90%, the concentration of SS in effluent is less 20mg/L. On the contrary, they are not good at removing NH4+-N, average removal ration is less than 3%. 8)In the conditions of using anaerobic enzyme catalysis biological film as a filler of the constructed wetland bed , Chongqing local plants such as rhubarb and calamus, can get used to the constructed wetland quickly and grow well in different sewage concentration, they can be the plants in the constructed wetland. Water hyacinth cannot get used to high concentration sewage while grows well in middle or low concentration, so it can be planted in middle or latter section. Cannas and Maranta nend a long time to adapt the sewage and not get used to grows well in high concentration ,it only be plants in the latter of constructed wetland. If planting rush in the wetland system with low concentration sewage, it cannot growth well for a long time. This indicated that cannot be plant in the wetland that using anaerobic enzyme catalysis biological film as a filler.
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