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NUMERICAL STUDY ON ENVIRONMENTAL IMPACTS OF THE THIRD SHANGHAI SEWERAGE PROJECT

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international Journal of Sediment research 2002年第2期17卷 165-173页

作者： Cheng LIU1, Yun HE2. Joseph Hun-Wei LEE3 and Zhao-Yin WANG4 1 Dr., Asso. Prof., international research and {2. center on erosion and sedimentation, beijing, 100044, china & Anhui Institu Dr. Asso. Prof. International Research and Training Center on Erosion and Sedimentation Beijing 100044 China & Anhui Institute of Architecture Hefei 230022 China Lecturer Anhui Institute of Architecture Hefei 230022 China Prof. The University of Hong Kong Hong Kong China Prof. Dept. of Hydraulic Engineering Tsinghua University & International Research and Training Center on Erosion and Sedimentation Beijing 100084 China

Two-dimensional hydrodynamic simulation for the Yangtze Estuary is performed by using the Delft3D model adopting the shallow water equations and the finite volume method on a curvilinear body-fitted grid. The model is calibrated and validated using available tidal data and field measurements. The velocity vector fields, the tidal levels, the trajectories of drogues and the far field sewage dilution from the existing and proposed outfalls are studied for the spring/neap tide and the dry/wet season. The results show that the tidal currents and the runoff flow are able to dilute and disperse the sewage from the outfalls to the outer sea. The sewage dilution contours under various hydrodynamic conditions indicate that the discharged effluent at present have relatively minor impact on the water environment of the Yangtze Estuary; whereas the planned sewage plan would significantly deteriorate the water quality of the estuary in the absence of any treatment, especially during the neap tide of dry season. The drogue tracking shows that the effluent from the four outfalls will be transported downstream to the Hangzhou Bay. A study on the pollution due to the project and the self-purification capacity of Hangzhou Bay is proposed in addition to that of the Yangtze Estuary.

关键词： Hydrodynamic simulation Outfall Far field sewage dilution Drogue tracking

ENVIRONMENTAL PROBLEMS ASSOCIATED WITH SEDIMENT DEPOSITION IN GUANTING RESERVOIR

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international Journal of Sediment research 1986年 67-78页

作者： Zhang Qishun, Jiang Naisen and Lin Bingnan (P.N. Lin) research Engineer, Institute of Water Conservancy and Hydroelectric Power research (IWH R), {2., china. Adviser, IWHR Chairman of Advisory Council, international research and training center on erosion and sedimentation (IRTCES), Adjunct Professor, Tsinghua University, {2., china.

Guaming Reservoir serves to protect beijing from flood hazards and, together with Miyun reservoir, to supply the capital with water of good quality. It has contributed tremendously to the prosperity of the city. But the mode of its operation results in large amount of sediment being deposited in the reservoir. This in turn entails many environmental problems not fully anticipated at the time of planning of the reservoir. These problems, being technical as well as economical and socio-political,prove to be complex and difficult to solve. This article reports briefly on the environmental problems encountered and the present trend of thought on their possible solution.

关键词： ENVIRONMENTAL PROBLEMS ASSOCIATED WITH SEDIMENT DEPOSITION IN GUANTING RESERVOIR

EFFECT OF LAND USE CHANGE ON RUNOFFAND SEDIMENT YIELD

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international Journal of Sediment research 1999年第4期 37-44页

作者： Xiangdong Wang and Zhao-Yin Wang(Dr. china Institute of Water Resources and Hydro-power research, P.O.Box 366. {2. 100044. china)(Prof. international research and training center on sedimentation and erosion. P.O.Box 366, {2. 100044,china.)Notes:

Runoff and sediment yield are greatly affected by the type of land use. The paper studies the influenceof agriculture, husbandry, mining and urban development, demonstrates the law of variation in sedimentyield during the processes of land use changes. Land use changes from forest to agriculture, grassland tofarm field and slope plough land to terrace field exhibit the same law influencing the sediment *** the transforming period the sediment yield is higher than those of either land used and is provedto be equal to he sum of the sediment yields of the two types of land use. This is named thesuperposition law of land use transtbrmation. The correlation between the percentage of forest coveragewith the runoff and sediment yields indicates that the runoff yield reduce to the minimum and thesediment yield is nearly zero if the coverage is higher than 60%. Whereas the runoff is doubled andsediment is tripled for 10% reduction in the forest coverage if the coverage is between 30-60%. Miningand urbanization increase the sediment yield in the development period.

关键词： soil EFFECT OF LAND USE CHANGE ON RUNOFFAND SEDIMENT YIELD

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SCOUR RATE FORMULA

international Journal of Sediment research 1997年第3期 11-20页

作者： Zhaoyin WANGProf Dr., international research and {2. center on erosion and sedimentation. P.O.Box 366, beijing 10044, china Jinchi HUANG Dr. Senior Engineer, china Institute of Water Resources and Hydro-Power research,P.O.Box 366, beijing 100044. Chi

In alluvial streams bed scour often occurs if the sediment load is less than the capacity of the flow. Two types of scour are identified, namely local scour and channel bed scour. Many studies have been devoted to local scour but very few to the channel bed scour. Channel bed scour can be further classified according to their causes as flood scour, downstream reservoir scour, hyperconcentrated flow scour and channelized river scour. The scour depth depends on the scour rate and duration of scour. More than 100 experiments were conducted to investigate the laws of scour rate. It is found that the scour rate is proportional to the stream power of flow and the steeper the slope and the finer the cohesionless sediment, the higher the scour rate will be. A scour rate formula, the first of its kind, is proposed in the paper, which is proved valid for unsteady flow scour.

关键词： Scour rate, Channel bed scour Stream power, Bed load motion, Unsteady sediment transport

DISCUSSION　ON　“researchES　ON　ENVIRONMENTAL　CHANGES　AND　WATER　AND　SEDIMENT　TRANSPORT　OF　THE　YELLOW　RIVER　BASIN”

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international Journal of Sediment research 1996年第2期 69-72页

作者： WANG Zhaoyin and PANG Bingdond( international research and {2. center on erosion and sedimentation,P.O.Box 366,beijing 100044,P. R. china.)( beijing institute of Meteorology,46 Bat-Shi-Qiao Road,beijing 100081,P.R.china.)

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THE ADVERSE IMPACT OF HUMAN ACTIVITIES ON FLOOD CONTROL IN THE HUAIHE BASIN

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international Journal of Sediment research 1997年第3期 317-324页

作者： Hugen ZhU Associate Prof, Dept. Of Civil Eng., Hefei University of Technology, 2.0009 Hefei, china Zhaoyin WANG Prof, Dr. international {2. and training center on erosion and sedimentation, P.O. Box 366, beijing 100044 china Dieter PRINZ Prof.,

The Huaihe Basin covers a total area of about 2.9,000 sq. *** the end of 1993, there were up to 154.55 million people in this basin. The population density was about 576 people per sq. km. Huge human activities in conjunction with poor resource management and weak flood control ability, have resulted in much adverse impact on flood control. This paper deals with accelerated erosion and sedimentation of reservoirs and lakes, aggradation of river courses in the basin. and concerns the changes of flood characteristics due to human influenCe, which includes the changes of the average coefficient of flood-runoff and the flood unit hydrograph of the basin, as well as rising of flood stages.

关键词： Human activities Soil erosion sedimentation Flood control

Study of Ultra-drying on Vigor and Physiological Characteristics of Lespedeza bicolor Seeds

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Chinese Forestry Science and Technology 2010年第2期9卷 56-61页

作者： LIU Yan1 LIU Guangquan1,2.3 LI Qingmei4 DUAN Xinfang5 HOU Longyu1 1. international research and {2. center on erosion & sedimentation, beijing 100048, P.R. china 2. china Institute of Water Resources and Hydropower research, beijing 100048, P.R. china 3. Northwest Agricultural and Forestry University, Yangling 712.00, P.R. china 4. research Institute of Forestry, Chinese Academy of Forestry, beijing 100091, P.R. china 5. Institute of New Forestry Technology, Chinese Academy of Forestry, beijing 100091, P.R. china

Ultra-drying (in a desiccator with silica gel) and accelerated aging (50 oC, 30 d) of Lespedeza bicolor seeds from the arid and semiarid areas of northwest china were studied. The results showed that in the moisture content of seed ( 43?70 g/kg), germination percentage and vigor indices had no significant differences; ultra-dried seeds had a stronger anti-aging ability than those with natural drying, and the best MC for the storage was 43 g/kg. Therefore, it was feasible to store L. bicolor seeds with ultra-dried moisture content.

关键词： ultra-drying germination percentage vigor index relative conductivity enzyme activity Lespedeza bicolor

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Effect of Ultra-drying on Vigor and Physiological Characteristics of Ziziphus jujuba var spinosa Seeds

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Chinese Forestry Science and Technology 2009年第4期8卷 34-40页

作者： LIU Yan1 LIU Guangquan1,2.3 LI Qingmei4 DUAN Xinfang5 HOU Longyu1 1. international research and {2. center on erosion & sedimentation, beijing 100048, P.R. china 2. china Institute of Water Resources and Hydropower research, beijing 100048, P.R. china 3. Northwest Agricultural and Forestry University, Yangling 712.00, P.R. china. 4. research Institute of Forestry, Chinese Academy of Forestry, beijing 100091, P.R. china 5 Institute of New Forestry Technology, Chinese Academy of Forestry, beijing 100091, P.R. china

Using ultradry method and accelerated aging, storage behavior of Ziziphus jujuba var spinosa seeds with MC of 15-80 g/kg was studied. The results showed that seeds with MC of 2.-80 g/kg could maintain the stabilization in germination percentage, vigor, relative conductivity, and enzyme activities; and during the ageing the seed storability increased with the moisture content decreased to 2. g/kg. Thus, it was feasible for the seeds to be stored under the ultra-dried condition.

关键词： ultra-drying germinability vigor enzyme activities Ziziphus jujuba var spinosa

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Effects of Ultra-drying on Vigor and Physiological characteristics of Hippophae rhamnoides Seeds

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Chinese Forestry Science and Technology 2010年第1期9卷 53-59页

作者： LIU Yan1 LIU Guangquan1, 2. 3 LI Qingmei4 DUAN Xinfang5 HOU Longyu1 1. international research and {2. center on erosion and sedimentation, beijing 100048, P.R. china 2. china Institute of Water Resources and Hydropower research, beijing 100048, P.R. china 3. Northwest Agricultural and Forestry University, Yangling 712.00, P.R. china 4. research Institute of Forestry, Chinese Academy of Forestry, beijing 100091, P.R. china 5. Institute of New Forestry Technology, Chinese Academy of Forestry, beijing 100091, P.R. china

Studies of ultra-drying and accelerated aging on Hippophae rhamnoides seeds from the arid and semiarid areas of northwest china were conducted. The results showed that H. rhamnoides seeds had higher desiccation endurance. When seeds were desiccated to 2. g/kg, their germination percentage, vigor indices and enzyme activity could be retained. After 30-day accelerated aging, ultra-dried seeds had better anti-aging ability and storability compared to natural dried seeds, and the best choice for the MC of seed was 34 g/kg. Accordingly, ultra-drying treatment could improve the storability.

关键词： ultra-drying accelerated aging seed vigor enzyme activity Hippophae rhamnoides

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