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Journal of IWHR Vol.4, No.1 JUN, 2000 |
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Journal of IWHR Vol.4, No.1 JUN, 2000 |
| Flood Resources and Flood Utilization | Xiang Liyun; Jiang Furen |
| Research on the Reasonable Allocation of Water Resources in Xinjiang | Yin Mingwan; Han Suhua; Ding Min; Ma Jing Zhang Yi; Guo Chunhong |
| Water Resources Allocation Optimization Model and Options for Ningxia | Xie Xinmin; Qin Dayong; Yu Fuliang; Wang Lin |
| Ruan Benqing; Pei Yuansheng | |
| The Problems and Countermeasures on Agricultural Sewage Irrigation in China | Yang Jifu |
Research on the Water Requirement for Sediment Transport of the Lower Yellow River |
Huang Jinchi; Liu Shukun |
Zhou Wenhao; Chen Jianguo; Yuan Yuping |
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Study on Protective Areas of Yellow River Dyke in Lower Reaches |
Li Na; Yang Lei; Liu Shukun |
| Wang Gang; Xu Mingquan | |
Research on FEM for Environmental Effects Due to Ash Waste Water from Power Plant Ash Storage Dam |
Xu Guoan; Wu Guisheng |
Liu Lanfen; Gao Xueqing; Wang Zhijun |
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Li Chong; Lu Jikang; Li Xiaopei |
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Reference Information Resources and Indexing Method on Internet Web |
Yang Zhi |
①
Being influenced by the policy,the irrigation water diverted from the Yellow River has a great sudden change process from 1958 to 1962.With the irrigation scale increasing gradually,the irrigation water diverted from the Yellow River increased by 6% annually from 1965 to 1989.Being affected by the Yellow River runoff,the irrigation water is restricted to a certain degree.②
There are two peaks of the irrigation water diverted from the Yellow River annually,being in april and ugust respectively.The total irrigation water diverted from the Yellow River from March to June is over 50% of annual irrigation water diverted from the Yellow River.The total irrigation water diverted from the Yellow River from March to September is over 80% of annual irrigation water diverted from the Yellow River.The irrigation water diverted from the Yellow River increased greatly from November to next year's April since 1990.③
The space distribution of irrigation water diverted from the Yellow River varies greatly with time.In the seventies, the Yellow River water use of Henan province is 40% of total water use,and Shandong province is 60%.In the eighties,Henan province is 30%,Shandong province is 70%,and from 1990 to 1995,Henan province is 25%,Shandong province is 75%.④
The irrigation area,the conditions of climate,and the Yellow River runoff(especially variation of the Yellow River runoff in dry period) are main factors influencing irrigation water diverted from the Yellow River.For example, from 1985 to1995,the irrigation norm decreased year after year,but the proportion of the Yellow River water use increased from March to June,Reaching a maximum of 84.5% ofthe Yellow River runoff.Excessive water use in dry period is a maim cause of the Yellow River current dry-up. Key words the lower Yellow River irrigation district, irrigation water,characteristics,analysis.First,an overall investigation about water resources of the sewage irrigation across the country,the sewage irrigation area,the crops and the mode of sewage irrigation should be proceeded.On this basis,the scientific planning should be carried out for ensuring the balance of water-soil environment in the irrigation area.At the same time,the respective departments should strictly control the unqualified sewage discharge.
Second,pre-treatment of sewage in oxidizing pond,sewage soil treatment system,sewage ecological treatment system and so on should be promoted,so that the harmful impact of the primeval sewage on soil and crops can be reduced.
Third,all-round resesrch of sewage irrigation technology should be developed.The sewage irrigation effects on the quality and quantity of agriculture products,soil fertility and crop physiology and biochemistry should be made.The safety bearing capacity on main harmful substance and organism in different soil-plant system should be defined.The sewage irrigation technique for main crops should be studied through investigation.
Fourth,the sewage irrgation standardized administrative system should be established so that the sustainable development of sewage irrigation can be ensurde through monitoring system and organization management. Key words sewage irrigation,problems,countermeasures. CONTENTS
The “92.8”flood brought about a lot of damages,including inundation of 40,000 ha of farmland on the floodplain of the Lower Yellow River.Based on field investigation,analysis on specific features of the flood is presented in this Paper.
The extremely high water stage,occurred in Huayuankou Hydrometric Station was caused directly by the previous deposition in the main channel and unfavorable combination of incoming flow and sediment regime.But the primary cause is the change in out going runoff and sediment load from the Upper and Middle Yellow River.Since the middle 1980's remarkable reduction has taken place in the Lower Yellow River both in runoff and sediment load.Further reduction of them in the future seems to be a definite tendency.As some unforeseen troubles in flood control in Lower Yellow River might occur,more attention should be paid for it. Key words Yellow River,hyperconcentrated flood,discharge,level,changes in runoff and sediment load.
Only a small portion of ash waste is comprehensively used.Most of them should be stored some harmful substances of ash waste may affect water environment from seepage.This Paper discusses the affect of seepage on water environment in a shore plain type ash storage plant.
For the shore plain type ash storage plant.Its groundwater level varies slowly.The upper strata mostly are loams and silty loams with low seepage coefficients,therefore seepage velocity are low.A groundwater quality model is established.This model is considered as heterogeneous anisotropic.Under pressure and non-pressure,with stable and non-stable conditions.The Program can be used for two and three dimensional seepage problems for different heads and seepage quantities.The Program can establish phreatic lines.It has pre-process and post-process interactive functions.It can crate networks automatically.The model can be used for convection,dispersion and absorption conditions.
A practical example with theoretical analysis is compared with The Program,Their vesults are in close agreement.
The ash water seepage and groundwter quality problems of wang ting power plant was studied.First the hydraulic environment parameters were established with back analysis, then the PH and F for ground water quality were calculated and compared with practical measurement in field.Their vesults are in close agreement.At the same time seepage problems were computed by two dimensional method,for different seepage control measures.The results show that the design of ash storage dams must consider not only dam Ntalility lot also groundwater contamination problem.The optimum solution would lie the utilization of anti-seepage measures or ash water reuse to minimize pollution problems.
Key words ash water pollution,ground water quality model computation,seepage control measure.A combination of field monitoring,simulation modelling and numerical calculation was used as an approach to study the relation between water temperature and lake eutrophication.The main content of the Paper is as follows:
1.The Status Water Environment Assessment.The assessment is made on the basis of a lot of field monitoring data.They include the water quality assessment, the effect of substrate sludge releasing on water quality,and the eutrophic state assessment.
2.Calculation of the Nutritional Load into the Lake from the Power Plant. The predicted results were:total nitrogen 11.1 ton per year,consistency 0.15mg/l, total phosphorus 2.1 ton per year,consistency 0.02mg/l.
3.Prediction of the Thermal Diffusion Region of Cooling Water Discharge. The 2-dimension mathematical model was applied to predict the temperature distribution of thermal discharge.First,the model was verified by monitored status water temperature distribution and the parameter values were determined.Then,the area of influence range was predicted as about 2.5km2，the average temperature rise was predicted as about 2.0℃。
4.Effect of Temperature Rise in the Local Lake on Eutrophic State of Water Body.Three subjects were studied. 1)To analyze the variations of community and biomass of floating algae in the water body due to water temperature rise according to AGP experiment. 2)To predict the concentration of chlorophyll-a in the water body after water temperature rise.The 2-dimension first order single step ecology model was used on the basis of the 2-dimension hydrodynamics and thermodynamics model.The parameter valuses were checked and determined with AGP experimental values. 3)To predict the content of dissolved oxygen due to water temperature rise.
5.The conclusions were drawn on the basis of the above analyses and prediction. After the reconstruction of power plant,the nutritional substance will not be discharged into the lake by the power plant,the cooling water alone cannot worsen the eutrophic state of water body. Key words eutrophication,nutritional load,algae community,substrate sludge releasing.
Jingjiang Flood Detention Area in Hubei Province was selected as pilot study project.The flooding process can be simulated numerically through the hydraulic method,at the same time,the salient elements of flood,such as the inundated zone,water depth,and flow velocity etc,can be shown as map layers.GIS commercial software,such as MapInfo,can provide a powerful tool to deal with base spatial graph.VB,as a rapid software-making tool,has played an important role in Windows application.So,integrating re-creation method,based on the rapid software-making advantages of VB,combined with the features of GIS,and in conjunction with hydraulic numerical model,was used to make the Flood Risk Map of Jingjiang Flood Detention Area.From the application system,more information,such as the flood characters,geographic elements,engineering layout,and social-economic factors etc,can be obtained and classified rapidly and effectively.In this way,the pilot flood factors distribution graphs and special charts can be worked out directly.Of coures,flooding process was displayed visually in the application system,and the evacuation routes for residents living in Jingjiang Flood Detention Area also can be shown visually as moving label and text information.Such Kind of flood risk map can provide strong basis for the assessment of flood hazard,rehabilitation efforts,land utilization, and so on.
As a whole,the integrating re-creation method which combines the advantages of both VB and GIS, and in conjunction with hydraulic method,can become a powerful rapid tool,and play a more important role in the digital flood risk map-making. Key words flood risk map,GIS,hydraulic model,integrating re-creation method.
Key words
internet,indexing tool,information resource,reference of water conservancy.