Study On The Scenic Water Purification By Ecological Floating Bed

This paper we selected Canna generalis and Iris pseudacorus as the tested plants which were planted in the ecological floating beds. Based on the static simulation tests, we analyzed the purification effects and rules of ecological floating bed technology on polluted scenic water body, and also the effects of the technology on controlling the water quality of reclaimed water in scenic waters. The experiments were carried out in four water tanks:CK, Canna generalis, Iris pseudacorus and mixed planting system of both plants. Conclusions were summed up as the following:Firstly, the test of purification effects among the four treatments showed that both Canna generalis and Iris pseudacorus grew well and the purifying efficiency of planted treatments were superior to unplanted treatments significantly. Iris pseudacorus gives the highest removal rate of TN, the result is 69.4%; Canna generalis gives the highest removal rate of TP, the result is 70.5%; the mixed floating bed system gives both good removal rates of TN,TP, the results were 47.8%,56.8%. So both the two plants could be used to purify polluted scenic waters.Secondly, based on the previous experiment, the test of purification effects of the reclaimed water reused in landscape water body was conducted. Because of the plants have grown to the peak, the quantity of pollutants removed by plants reduce. Microbial metabolism played a significant role in the pollutants removal, so the removal rates of all the three floating bed systems were close to each other. The TN removal rates of Canna generalis, Iris pseudacorus and mixed planting system were 40.3%,51.2%,49.9%, the TP removal rates were 46.2%,41.0%,46.7%, the NH4+-N removal rates were 99.1%,98.8%,98.7%, the CODMn removal rates were 31.0%,32.6%,34.0%. Thirdly, by analyzing the relationship between the removal rates of TN,TP and the length of test time, we can find that the rules of pollutants removal were conform to the cubic function. The interrelation coefficients of the fitting curves were more than 0.92, even to 0.99, so it can be calculated that the removal effects of TN,TP will grow better as the test time goes.In conclusion, the ecological floating bed technology could be applied widely as one of high efficient and economic biology restore technology in improving water quality of scenic water bodies.