In order to improve the source water quality of drinking water and mitigate the load of drinking water treatment plant, a pilot test was conducted with integrated horizontal flow constructed wetlands to pretreat the w...In order to improve the source water quality of drinking water and mitigate the load of drinking water treatment plant, a pilot test was conducted with integrated horizontal flow constructed wetlands to pretreat the water supply in the reservoirs of Yellow River. Resuhs show that under the hydraulic loading rate of 4 m^3/（ m^2 · d）, the average removal rates of chemical oxygen demand （COD）, total nitrogen （TN）, ammonium nitrogen （ NH4 ^＋ - N）, nitrate nitrogen （ NO3 ^- - N）, nitrite - nitrogen （ NO2^ - - N） and total phosphorus （TP） in the horizontal flow constructed wetlands are 49. 68% , 53.01%, 48.48%, 53.61% , 62. 57% and 49. 56%, re- spectively. The study on purifying mechanism of the constructed wetlands indicates that the disposal of contamination by subsurface wetlands is the combined actions of physical chemistry, plants and microorganism.展开更多
After the completion of the Three Gorges dam, a 30 m high water-level-fluctuating zone （WLFZ） will appear along the banks, and will form a seasonal wetland ecosystem. According to the program of storing water in the...After the completion of the Three Gorges dam, a 30 m high water-level-fluctuating zone （WLFZ） will appear along the banks, and will form a seasonal wetland ecosystem. According to the program of storing water in the Three Gorges reservoir, the main ecological and environmental problems probably incurred in WLFZ are discussed, such as formation of contaminated belt along banks, appearance of epidemic diseases in the reservoir region （including urban districts）, aggravation of geologic disasters, degradation of biodiversity and exacerbation of the ecosystem vulnerability. Six items of strategies are put forward according to the causes, distributed features and trends of these problems in this paper.展开更多
Water-sediment regulation of the Yellow River is to regulate and control the flow and sediment transport relationship of the lower reaches through reservoirs on the main streams and tributaries to create balance betwe...Water-sediment regulation of the Yellow River is to regulate and control the flow and sediment transport relationship of the lower reaches through reservoirs on the main streams and tributaries to create balance between water and sediment so that sediment transport capacity of the downstream channels can be maximized,shrinking of channels be contained,and medium flood channel be restored and maintained.Many years' research by the Yellow River Conservancy Commission(YRCC) reveals the water and sediment transport relationship that will prevent sedimentation at the downstream river channels.Based on this relationship and coming sediment and water conditions in the Yellow River basin,the YRCC,with maximized use of reservoirs on the main streams and tributaries,has developed three models of water-sediment regulation:single Xiaolangdi Reservoir-dominated regulation,space scale water-sediment match,and mainstream reservoirs joint operation.Ten water-sediment regulations based on these three models have resulted in an average drop of 1.5 m in the main channel of the downstream 800 km river and an increase of carrying capacity from 1800 to 4000 m3/s.Besides,the wetland ecosystems of estuarine delta has also been improved and restored significantly.展开更多
基金Sponsored by the National High Technology Research and Development Program (863) of China (Grant No.2006AA06Z303)the National Natural Sci-ence Foundation of China(Grant No.40671004)the Program for Young Academic Backbone of Harbin Normal University(Grant No.KGB200821)
文摘In order to improve the source water quality of drinking water and mitigate the load of drinking water treatment plant, a pilot test was conducted with integrated horizontal flow constructed wetlands to pretreat the water supply in the reservoirs of Yellow River. Resuhs show that under the hydraulic loading rate of 4 m^3/（ m^2 · d）, the average removal rates of chemical oxygen demand （COD）, total nitrogen （TN）, ammonium nitrogen （ NH4 ^＋ - N）, nitrate nitrogen （ NO3 ^- - N）, nitrite - nitrogen （ NO2^ - - N） and total phosphorus （TP） in the horizontal flow constructed wetlands are 49. 68% , 53.01%, 48.48%, 53.61% , 62. 57% and 49. 56%, re- spectively. The study on purifying mechanism of the constructed wetlands indicates that the disposal of contamination by subsurface wetlands is the combined actions of physical chemistry, plants and microorganism.
基金Thanks the financial support from National Natural Science Foundation of China （#40561006）, National Natural Science Foundation of China （06XYJ017）, and Key Foundation of Chongqing Normal University （08XLZ13）.
文摘After the completion of the Three Gorges dam, a 30 m high water-level-fluctuating zone （WLFZ） will appear along the banks, and will form a seasonal wetland ecosystem. According to the program of storing water in the Three Gorges reservoir, the main ecological and environmental problems probably incurred in WLFZ are discussed, such as formation of contaminated belt along banks, appearance of epidemic diseases in the reservoir region （including urban districts）, aggravation of geologic disasters, degradation of biodiversity and exacerbation of the ecosystem vulnerability. Six items of strategies are put forward according to the causes, distributed features and trends of these problems in this paper.
文摘Water-sediment regulation of the Yellow River is to regulate and control the flow and sediment transport relationship of the lower reaches through reservoirs on the main streams and tributaries to create balance between water and sediment so that sediment transport capacity of the downstream channels can be maximized,shrinking of channels be contained,and medium flood channel be restored and maintained.Many years' research by the Yellow River Conservancy Commission(YRCC) reveals the water and sediment transport relationship that will prevent sedimentation at the downstream river channels.Based on this relationship and coming sediment and water conditions in the Yellow River basin,the YRCC,with maximized use of reservoirs on the main streams and tributaries,has developed three models of water-sediment regulation:single Xiaolangdi Reservoir-dominated regulation,space scale water-sediment match,and mainstream reservoirs joint operation.Ten water-sediment regulations based on these three models have resulted in an average drop of 1.5 m in the main channel of the downstream 800 km river and an increase of carrying capacity from 1800 to 4000 m3/s.Besides,the wetland ecosystems of estuarine delta has also been improved and restored significantly.
