• 全国中文核心期刊
  • 中国科技核心期刊
  • 美国工程索引(EI)收录期刊

1995 Vol. 6, No. 4

Display Method:
Laboratory Study for Influence of Air on the Infiltration Flow in the Soil Unsaturated Zone
Tang Haixing, Su Yishen, Liu Bingao
1995, 6(4): 263-269.
Abstract:
The regularity of the formation,development and disappearance of air pressure in the soil unsaturated zone for rainfall infiltration,and also its influence on the infiltration flow were investigated by the special experimental system.Meanwhile,combining with formation analysis the conditions forming air pressure were approached,and the relationship between air pressure,total potential of soil moisture and groundwater table was also examined and explained.When the groundwater table is more shallow (<2m),the experimental results show that the total ponded infiltration water affected by air pressure will reduced by one-third.
A Solution Method for the Large-Scale Multi Objective Linear Programming
Ye Bingru, Fang Daonan
1995, 6(4): 270-277.
Abstract:
Multiobjective linear programming (MOLD) is one of the foundamental topics in studying the general multiobjective programming.The current adopted methods for solving such a problem seem not so effective.and sometimes not so strict theoretically.For example,the well-known weighting method is rime-consuming and also easy to leave out some part of total non-inferior solution set.While other analytical methods like the multiobjective Simplex Method require usually a lot of computation work.In this paper we present an analytical method (called the least reduction rate method) for solving a large scale multiobjective linear programming,which not only gives a strict and complete solution set,but also requires relatively much less computational work.The proposed method may be applied to solve strictly the large-scale,multiobjective quadratic program equally well.
Study on the Field Moisture Movement Numerical Simulation for Winter Wheat and the Irrigation Model under Sprinkler Irrigation Condition
Hu haoyun, Xie senchuan, Hui shibo
1995, 6(4): 278-284.
Abstract:
To investigate water-saving sprinkler model,both numerical simulation and field experiment methods are used to study the field moisture movement of winter wheat under sprinkler irrigation.Compared of the soil moisture between numerical simulation and the field experiment data,the results are satisfactory and indicate that the numerical model is reliable.Based on the model,the transpiration,surface evaporation and deep percolation under different sprinkler irrigation yuota are simulated.The results show that the surface evaporation and deep percolation under 40-60mm sprinkler irrigation yuota is minimal.Thus,the reasonable sprinkler irrigation model for winter wheat is proposed.Relative to the present sprinkler irrigation farmer's usage water use of the suggested model is reduced by 45%.
Calculation Method of the Ratio between Crop Leaf Transpiration and Soil Evaporation from Farmland
Kang Shaozhong, Zhang Fuchang, Liu Xiaoming
1995, 6(4): 285-289.
Abstract:
Based on the measured net radiation data above the canopy and on the soil surface under the crop canopy in winter wheat and summer corn field,a calculation model of the ratio between crop leaf transpiration and soil evaporation from farmland has been established in this paper.The model can express the physical oaring laws of the ratio correctly and is practical and useful.The research result shows that the ratio between leaf transpiration and soil evaporation a is increased with the leaf area index increasing,has a daily change and is higher in mid-noon and lower in the early morning and near night.The daily change process is influenced by leaf stomata movement.
GIS and Its Application in Hydrology and Water Resources
Zhang Jianyun, A. Dowley, M. Bruen
1995, 6(4): 290-296.
Abstract:
In this paper,the questions,such as what is a GIS (Geographical Information System)?what can a GIS do? and how to select GIS in an application? were discussed.The applications of GIS in hydrology and water resources in last decade were also summarised briefly.Finally,the Decision Support System for Water Management at Catchment scale(DSS-C W M)Based on GIS (the ARC/INFO method),which was developed by the Centre for Water Resources Research,University College Dublin,Ireland,was introduced as a case study.
One Dimensional Mathematical Model of Water and Sediment Routing in the Yellow River Mouth Reach
Chen Jieren, Chen Guoxiang
1995, 6(4): 297-303.
Abstract:
According to the characteristics of coming water and sediment,evolution of erosion and deposition of channel in the Yellow River mouth reach,the onedimensional mathematical model of water and sediment routing is developed from downstream Lijing station,considering ununiformity of flow and sediment in cross section,flow friction,extension of river mouth delta.The model is used to compute flow and sediment transport and river channel.The results agreed with the field data.The model can be used to predict the water level,sediment concentration,erosion and deposition in the Yellow River mouth reach.
Soil Erosion Caused by on the Sloping Land Impacts of Raindrop and Its Simulation
Tang Liqun
1995, 6(4): 304-310.
Abstract:
Rainfall erosion and its influence factors have been analysed in this paper.The formula of impact force produced by raindrop is deduced with the Newton's second law of motion based on the law of rainfall erosion on upland of ridge-hill in Loess Plateau regions.1t is assumed that splash rate of raindrop correfates with erosion force of raindrop to be linear,and a splash rate formula of raindrop is developed.It is verified with measured data of runoff plat of Qiaogou catchment and the results are satisfactory.
Cross-Section Morphology of River
Yin Xueliang, Chen jinrong
1995, 6(4): 311-317.
Abstract:
Computing expression for the characteristic parameters of a river crosssection including flow Q,silt discharge Q5,silt concentration S and depth (H) width (B) ratio Hb is developed in the paper.The variation of cross-section and its expression are also discussed.The paper indicats that the usual relation,√B/H widely used needs to be further improved in expressing the variation of cross-section morphology.
Karst Water Model of Non-Closed Watershed
Wang Lachun, Shi Yunliang
1995, 6(4): 318-324.
Abstract:
Non-closed watershed is a common phenomenon of karst regions,therfore it is essential to handle non-closed watershed when estimating karst water resoutce.The paper takes Houzhai experiment basin located at Puding county,Guizhou province as a case study to discuss the mechanism forming karst water.According to the surface and subsurface structures of the experiment basin,the paper develops a conceptual karst water model after dividing the experiment basin into four su卜basins and taking closeness degree of each sub-basin,which offers a new method to study non-closed karst watershed.
Reliability Study on Flood Forecasting in River Channel
Li Jiren, Zhang Silong
1995, 6(4): 325-330.
Abstract:
Combining channel flood forecasting scheme with reliability analysis methods,the paper studies the reliability analysis for flood forecasting.It analyses sources of uncertainty and treatment in calibrated madel,evaluates the effect of various uncertainties on forecasting,estimates the probabilities exceeding target peak discharges and makes quantitative reliability analysis for forecasting results.
Statistically Diagnostic Analysis on Regional Hard Rain in the Delta of the Yangtze River
Zou Jinshang, Wang Liang, Zhao Yansheng, Zhang Yimin
1995, 6(4): 331-335.
Abstract:
In this paper,synoptically and statistically classfied were types of regional hard rain influencing upon the delta of the Yangtze river.It was paied more attention to study the typhoon track,the coverage of hard rain and meteorological conditions causing hard rain of typhoon No.14 in 1962 (defined as "6214" typhoon).It was concluded that convergence line of inverted typhoon trough,south east jet in lower layer,upward motion,larger water vapour flux and stronger flux convergence are very important factors favorable to result in hard rain.
On Scienic Water Resources
Li Peicheng, Xue Huifeng
1995, 6(4): 336-340.
Abstract:
This paper discusses systematically the characters,duties,objects of study,work methods of scenic water resources.And it also reviews water resources research history,the present situation as well as its further developing direction.Scienic water resources is a new comprehensive subject of frontier science.Its objects of study are all-round natural scenery and all of the famous places with importment scientific and art significane.Its duty is to offer more quantity and good quality,perfect form and varied content resources for scenic water resource research,and to lay a solid substance foundation in order to establish many tourist places which are rich knowledge,more interests,beautiful landscape and having transport facilities.
Study of Field Mulching Techniques for Soil Moisture Conservation
Zhang yufang, Shen Rongkai, Ren Li
1995, 6(4): 341-347.
Abstract:
This paper introduces status of practical and theoretical study of the field mulching techniques at home and abroad.The models of the soil water and heat transfer are classified into two kinds:isothermal and non-isothermal.The representative models of these models and their features are analysed and described.The effects of surface mulch on the water,vapor and heat regime at the soil surface and the influence of different mulch material and different ways of mulching on soil water and heat transfer,and the two dimensional coupled soil water and heat models of numerical simulation are detailed.On the basis of summarising the results studied,some problems which need to be further researched are recommended.
Advance of Research on the Theory and Methodology of the Grey Modelling, Planning and Assessment of the Regional Water Environmental Quality
Zeng Guangming, Zhou Li, Yang Chunping, Guo Shenglian
1995, 6(4): 348-353.
Abstract:
This paper reviews the research on the theory and methodology of the grey modelling,planning and assessment of the regional water environmental quality at home and abroad,and the future development trend in this field is prospected.