Dissertation > Excellent graduate degree dissertation topics show

Study on Biological Restoration Technology in Drip Lake Diversion Channel

Author: ZhouYang
Tutor: XuYaTong；ZhangQiuZhuo
School: East China Normal University
Course: Environmental Science
Keywords: Drip Lake biological restoration ecological floating bed vegetation
CLC: X171
Type: Master's thesis
Year: 2011
Downloads: 116
Quote: 0
Read: Download Dissertation

Abstract

The Drip Lake is the largest artificial Landscape Lake in china. It is located in the southeast corner of Shanghai and adjacent to the East China Sea. Drip Lake is the representatives and symbol of Shanghai Lingang New City. The water of Drip Lake is transported from a lot of small natural river around Nanhui District. According to the water quality status monthly reported by Shanghai hydrologic central station and Shanghai water environment monitoring center. The quality of the Drip Lake source was between in standardⅣand inferior standard V. Based on chemical parameters as total nitrogen(TN)and total phosphorus(TP),the lake quality is now had been on the status of Low-Middle eutrophic condition, and tends to be eutrophic. Beacause of the lake eutrophication develops rapidly and hard to. be controled. It is urgent for us to reduce the entering water pollution load, such as nitrogen and phosphorus content in particular.The improvement of entering water quality plays a very important role in improving the water environment of lakes. Taking the C-port, mian diversion channel of Drip Lake, as the research object, "ecological floating bed", "submerged plants" and "floating plants" were used in the experiment site. Intend to improve the water quality of the diversion channel water environment, further improve the water quality of Drip Lake. The research results are followed:(1). The water purification capacity of ecological floating bed was proved by a series small experiment started in July,2009.During the static experimental period,the net removal of CODMn, TN and TP were 16.9%,50.3% and 50%.The removal rate was fast at the beginning of this period. The removal of the pollutants during the dynamic experimental period was lower than the static experimental period. When the hydraulic retention time(HRT)was shorter,the removal of CODMn, TN and TP was less. When the hydraulic retention time was 15 d, the net removal of CODMn, TN and TP were 18.6%,45.6% and 42.3%.The removal was lower when the hydraulic retention time reduced. When the hydraulic retention time was 4.5 d, the net removal of CODMn, TN and TP were 9.4%,36.6%and 39.8%.(2). The Biological Restoration technology used in Drip Lake diversion channel played an important role in water purification. During the 9 months static experimental period, the average net removal of CODMn, TN, NH3-N and TP were 19.7%,23.9%,20.3% and 19.1%..(3). The removal of the pollutants during the dynamic experimental period was lower than the static experimental period.. The removal of CODMn and TN was lower than 10%, The Biological Restoration technology nearly have no removal in TP.(4). The removal of pollutants by Biological Restoration technology used in Drip Lake diversion channel had an obvious seasonal change. The removal of pollutants in spring and autumn was higher than winter.(5).Comparison between 2008 and 2010, the results of the removal of pollutants in two years have a small change. The water quality of sites B in 2010 was a little better than 2008.The average removal of CODMn, TN, and NH3-N lower than 2008. Overall, The Biological Restoration technology had a steady capacity to remove the pollutants away from the Drip Lake diversion channel.(6).During the 9 months static experimental period, the biomass of Irispseudacorus L. increased 2597.7g/m2.The biomass is reduced between december and the next february. Through the harvest in december,37.7kg nitrogen and 13.5kg phosphorus were removed from the water bidy. The total number of becterica of Irispseudacorus L.’s roots is 1.3 X 106, higher than the water in Drip Lake diversion channel.

Related Dissertations

CLC: > Environmental science, safety science > The basic theory for the Environment and Science > Environmental Biology > Ecosystems and pollution ecology
© 2012 www.DissertationTopic.Net Mobile