Water Purification And Ecological Remediation For Cityscape Water In Northwest Region

with the population increasing and society economy developing rapidly, the amount of water demand rises dramaticly, and water environmental pollution also is increasingly serious, the amount of water for ecosystem need is hardly assurance, in addition to the influence of the industry and residents, the water system in the city is shrinking gradually, Eutrophication of inside lakes is more and more serious, the city water ecosystem declines seriously, it is very essential to control cityscape water pollution situation. The cityscape water body regarded as the important component and elementary producers of the urban ecosystem, demonstrated its irreplaceable function and meaning in urban ecology construction. This subject aimed at the quality of cityscape in Xi'an, mainly by an on trial method, developing water quality improvement technology for cityscape water.Protecting landscape water body mainly controlled its content of COD BOD5 TN and TP and the growth of algae, keeping it clean and the whole water quality. This reaserch was about constructed biological floating beds treating Xingqing and Geming Lake of Xi'an with cultivating Scindapsus aureus, Canna generalis and Monstera.Main work and the conclusions of experiment:(1) Investigated and analyzed the water quality actuality of main scenery water in Xi'an, collected the water quality monitoring data, and evaluated the water quality. The result expresses: the quality of most scenery water in Xi'an is not optimistic, Lianhu Park water, Xingqing lake water are the Category V, Xi'an moat water and Geming Park water are the Category inferior V, which all don't reach the Category C in scenery and entertainment water quality standard and have the trend of becoming worse. They are in dire need of taking measures to be improved. (2) Completed Static experiments which carried on by biological floating bed and biological contact oxidation combination technique.(3) The plants could purify water quality effectively, also afforest and beautify the view, which had good ecological benefits. The plants chosen in this test was relatively suitable for the climate of Xi'an, and had relatively long green issue, could be as a principal choice for plant species of treating landscape water in north temperature zone.(4) The experiment showed that biological floating bed and biological contact oxidation combination technique had a good effect on water purification, especially on the removal of nutriment such as nitrogen, phosphor etc in water. The result of test showed that the removal rate of TN reached 49.8%-84.4%,the removal rate of NH₄⁺-N reached 77.4%-97%, the removal rate of TP reached 57.1 %-92.9%, the removal rate of COD_Mn reached 19%-50%. And the growth status of economic terraneous plant is perfect, biology quantity increased quickly. It proves that this technique to improve the scenery water quality is viable and worth of expansion.(5) Aimed at the characteristics of water environment in northwest region, put forward the biological-ecological treament and suggest to adopt different technique combination to improve the water quality of lake and river landscape water. The main methods are the reconstruction and instauration of hygrophilous vegetation, biology manipulation, spraying microorganism, ecological slope protection and biological floating bed and biological contact oxidation combination technique.