5　Conclusion and Outlook

Recently,ecological management has gained wide attention.Ecological floating bed technology is an important direction for studying sewage treatment and ecological restoration owing to the excellent performance and remarkable ecological benefit.When using this technology,however,there are several problems that require attention to ensure a stable purifying effect and maintain a sustainable landscape:firstly,there is need to combine local ecological environment and pollutant load when designing ecological floating bed system;secondly,selecting and ascertaining of pollutant characteristics and water geochemical characteristics;thirdly,there is need to give attention to some problems such as vegetation management and artificial medium regeneration during the running of the processes.

Our reformation of the ecological floating bed structure mostly is confined to scientific research,but the floating bed with plants only is used commonly in practice.There are two reasons:on the one hand,compound ecological floating bed is more complicated and it is difficult to form modular production though it has better purifying effect;and in order to adapt to the ecological restoration of largescale rivers and lakes,we must further improve this system.On the other hand,it is difficult to regenerate fillers due to the complex structure of compound ecological floating bed although the absorption of the filler can strengthen the handling ability for contaminants.With developments in biology,materialogy and other subjects,the ecological floating bed will get further improvement and become another technology widely used in the ecological restoration field.