ANALYSIS ON THE SENSITIVITY OF THE FLUVIAL PROCESS IN ALLUVIAL RIVER

ＡＮＡＬＹＳＩＳＯＮＴＨＥＳＥＮＳＩＴＩＶＩＴＹＯＦＴＨＥＦＬＵＶＩＡＬＰＲＯＣＥＳＳＩＮＡＬＬＵＶＩＡＬＲＩＶＥＲ￥ＣＡＯＷｃｎｈｏｎｇａｎｄＺＨＡＮＧＱｉｓｈｕｎ（ＲｅｓｅａｒｃｈＥｎｇｉｎｅｅｒ，ＩｎｓｔｉｔｕｔｅｏｆＷａｔｅｒＣｏｎｓｅｒｖａ...     

INFLUENCE OF THE UPSTREAM RESERVOIRS ON THE ADJUSTMENT OF DOWNSTREAM ALLUVIAL CHANNEL

I. INTRODUCTIONThe Yellow River is a heavily sediment--laden river. The sediment load of the Yellow River ranks the first in the world while its annual runoff is only of medium size. Toharness the river, it is necessary to build reservoirs for regulating runoff to meet the demands of economic development. Since the founding of PRC in 1949, I S4 large and medium--sized reservoirs have been constructed on the main stem and the tributaries with atotal storage capacity of 84.5 billion m3.…     

INTEGRATION OF THE MODELS OF ANNAGNPS AND REMM TO ASSESS RIPARIAN BUFFER SYSTEM FOR SEDIMENT REDUCTION

The United States Department of Agriculture (USDA) Annualized Agricultural Non-Point Source Pollution model (AnnAGNPS) is used to help evaluate a watershed response to agricultural management practices to control water quality. However, AnnAGNPS version 3.5 does not contain features to estimate the effect of a riparian buffer (RB) system on water quality. The Riparian Ecosystem Management Model (REMM) is used to simulate the impact of riparian buffer systems on water quality. However, frequently the lack of measured upland loadings that are required by REMM simulation limits the application of REMM. To address this data gap, a study was conducted to integrate AnnAGNPS with REMM for RB system simulation. AnnAGNPS was used to simulate water and sediment loadings from an upland field into a three-zone RB system at the Gibbs Farm located in the Georgia coastal plain. These AnnAGNPS outputs were used as the inputs to REMM. REMM was used to simulate water and sediment movement along the riparian buffers. The AnnAGNPS simulated amount of annual runoff at the edge of the field was close to observed amounts (Nash-Sutcliffe efficiency of 0.92). It is believed that a substantial portion of sand was removed from the runoff one meter into the grass buffer where the samplers were located; therefore, sand was excluded from the AnnAGNPS simulation for comparison with observed sediment. Excluding sand, the AnnAGNPS predicted amount of annual sediment matches the observed amount fairly well (Nash-Sutcliffe efficiency of 0.46). In addition, based on evaluating the percent reduction of sediment at each zonal interface, the AnnAGNPS/REMM model well simulated the function of the RB system to reduce sediment.     

ON THE VARIETY AND COMPLEXITY OF THE SHORT-TERM AND URGENT PRECURSORS OF THE TANGSHAN EARTHQUAKE

The Tangshan earthquake(M=7.8)which occurred on July 28, 1976 is the greatest event among the modern catastrophes in China. It occurred in a region that was the most densely networked with seismic stations, a region that had the longest history in seismological work and had received     

EFFECTS OF EXISTENCE OF SEDIMENT PARTICLES ON THE ENERGY LOSS OF FLOW

ＥＦＦＥＣＴＯＦＥＸＩＳＴＥＮＣＥＯＦＳＥＤＩＭＥＮＴＰＡＲＴＩＣＬＥＳＯＮＴＨＥＥＮＥＲＧＹＬＯＳＳＯＦＦＬＯＷ￥ＬＩＵＱｉｎｇｑｕａｎ；ＣＨＥＮＬｉａｎｄＬＩＵＤａｙｏｕ（Ａｓｓｏｃ．ＲｅｓｅａｒｃｈＦｅｌｌｏｗ，ＩｎｓｔｉｔｕｔｅｏｆＭｅｃｈａ...     

A NON-DIMENSIONAL COUPLED NUMERICAL MODEL OF ALLUVIAL FLOW

ＡＮＯＮ－ＤＩＭＥＮＳＩＯＮＡＬＣＯＵＰＬＥＤＮＵＭＥＲＩＣＡＬＭＯＤＥＬＯＦＡＬＬＵＶＩＡＬＦＬＯＷＳａｉｅｄＳＡＩＥＤＩ（ＴｈｅｔｅｘｔｉｓａｂｒｉｄｇｅｄｂｙＤｒ．ＤＩＮＧＬｉａｎｚｈｅｎ）（ＷａｔｅｒＲｅｓｅａｒｃｈＬａｂｏｒａｔｏｒｙ，Ｓｃ...     

ON THE NUMBER OF FRACTIONS TO COMPUTE TRANSPORT OF SEDIMENT MIXTURES

1 INTRODUCTIONMany hydro-momhological mathematical models neglect the innuence of river bed maerialheterogeneity and its time and space changes during transport and related erosion/dePosition processes. Inthese models a rePresentative diameter of the river bed grain-size distribution (for examPle d5o) isspecified as initial data in each comPutational point of the modeled domain. Different d5o can be assignedto each ghd point but temPoral changes in bed material gradation cannot be simula…     

THE CHARACTERISTICS OF RAINFALL AND DISASTERS OF DEBRIS FLOW IN BEIJING AREA

LINTRODUCTIONDisastersofdebrisflotvoccurfrequentlyinChina.Mostofthemareinrainstormtype.TherainStormdebrisflowiscausedbyStormrainfallthatinducesastrongStreamflowsonloosematerialsinwatershed.Theeffectsofprecipitationonthedebrisflowareasfollows(ChengduResearchInstituteC;DisasterandEnvironment,1989)f(l)Precipitationacceleratesthematerialsofloosedebristogather,(2)PrecipitationsuPPlywatercomponentofdebrisflow,(3)Precipitationprovidesdynamicconditionsfordebrisflow,(4)Precipitationisatrigg…     

REGULATION OF FLOW AND SEDIMENT LOAD IN THE YELLOW RIVER

Small runoff, large sediment load, and incompatible relationship of flow and sediment load are very important characteristics of the Yellow River. They are also the crux of the most prominent problems of the Yellow River. To solve these problems, the regimes of flow and sediment load have to be improved by increasing water, reducing sediment load, and by using reservoirs to regulate flow and sediment load. The results of experiments for regulating the flow and sediment load in the last three years by the Xiaolangdi Reservoir have indicated that this measure is a realistic and effective way to mitigate the prominent problems in flood control of the Lower Yellow River at present and in the near future. However, the regulation system is still imperfect. It is advisable to speed up the pace of research and construction of the system for regulating flow and sediment load.     

DAM IMPACTS ON AND RESTORATION OF AN ALLUVIAL RIVER-RIO GRANDE, NEW MEXICO

1 INTRODUCTION The construction of more than 75,000 dams and reservoirs on rivers in the United States (Graf, 1999) has resulted in alteration of the hydrology, geometry, and sediment flow in many of the river channels downstream of dams. Additionally, hydrologic and geomorphic impacts lead to changes in the physical habitat affecting both the flora and fauna of the riparian and aquatic environments. Legislation for protection of endangered species as well as heightened interest in ma…     

USING THE K_3 ROUGHNESS COEFFICIENT TO MEASURE THE SPATIAL AND TEMPORAL VARIABILITY OF ROUGHNESS ON RIVER BEDS

ＵＳＩＮＧＴＨＥＫ_３ＲＯＵＧＨＮＥＳＳＣＯＥＦＦＩＣＩＥＮＴＴＯＭＥＡＳＵＲＥＴＨＥＳＰＡＴＩＡＬＡＮＤＴＥＭＰＯＲＡＬＶＡＲＩＡＢＩＬＩＴＹＯＦＲＯＵＧＨＮＥＳＳＯＮＲＩＶＥＲＢＥＤＳ￥ＣａｒｍｅｎｄｅＪｏｎｇ（ＰｏｓｔｄｏｃｔｏｒａｌＦｅｌｌｏ?..     

ANALYSIS ON THE DEBRIS FLOW SURGES

ＡＮＡＬＹＳＩＳＯＮＴＨＥＤＥＢＲＩＳＦＬＯＷＳＵＲＧＥＳ￥ＷａｎｇＧｕａｎｇｑｉａｎ（Ｐｒｏｆｅｓｓｏｒ，Ｄｅｐｔ．ｏｆＨｙｄｒａｕｌｉｃＥｎｇｉｎｅｅｒｉｎｇ，ＴｓｉｎｇｈｕａＵｎｉｖｅｒｓｉｔｙ）Ａｂｓｔｒａｃｔ：Ｂａｓｅｄｏｎｔｈｅｆｕｎｄａ...     

ON THE USE OF MOVABLE-BED MODELS FOR RIVER PROBLEMS:A STATE-OF-THE-ART

I. INTRODUCTIONMore than a decade ago, under tile auspices of DELFT HYDRAULICS an overview on the use ofmodels for river problems was given (de Vries & van der Zwaard. 1975). Since then a better understanding of morphological processes in rivers has been obtained, their mathematical formulation hasbeen improved and computer facilities have been expended. Scale models and mathematical models arein use. but their field of application is gradually changing. It seems that the better ma…     

EXPERIMENTAL STUDY ON THE COHERENT STRUCTURE OF THE TURBULENT BOUNDARY LAYER IN OPEN-CHANNEL FLOW

1 INTRODUCTION The coherent structure of turbulence is the most important discovery of turbulence studies in the last several decades. The coherent structure is a joint spatial state (Liang, 1999). In this space, there exist all kinds of motions that are organized and related. Namely, strip structures, large vortical structures, and other organizing flows are present. In 1932, researchers found that turbulence wasn抰 a fully random phenomenon and came to realize that the repeated emergen…     

THE FORMING CONDITIONS OF ALLUVIAL RIVER CHANNEL PATTERNS

1 INTRODUCTION It is well known that the river channel patterns are determined by long-term water-sediment conditions. However, quantitative expressions for river channel patterns and their fluvial processes still remain not clear. Existing theories in this aspects, such as geomophological theory, theory of maximum energy consuming rate, stability theory, theory of probability, and statistic analysis, are developed based on certain simplified assumptions and can not be successfully used t…     

ON THE INFLUENCE OF TURBULENCE ON THE INITIATION OF SEDIMENT MOTION

1 PROBLEM DEFINITION Owing to the practical importance of the initiation of motion many researchers began to tackle this problem even at the beginning of the last century (e.g. Kramer (1932, 1935), Casey (1935)). Shields (1936, Fig. 1) developed a non-dimensional representation based on the measured data of Casey, Kramer, USWES and Gilbert, together with his own data based on investigations with succinite sand, lignite, granite chips and heavy spar. Despite the different material p…     

BREIF ILLUSTRATION ON THE SEISMIC ZONING OF THE SEA AREA OF CHINA AND ITS VICINITY

In 1986, the book of "countermeasure of earthquake" was published. In this book, it was pointed out that the countermeasure of earthquake in sea area have not been studied and need to study this problem in future. For studying the countermeasure in sea area, we have to compile a seismic     

ON THE REDUCTION OF WATER AND SEDIMENT YIELD OF THE YELLOW RIVER IN LATE YEARS

ＯＮＴＨＥＲＥＤＵＣＴＩＯＮＯＦＷＡＴＥＲＡＮＤＳＥＤＩＭＥＮＴＹＩＥＬＤＯＦＴＨＥＹＥＬＬＯＷＲＩＶＥＲＩＮＬＡＴＥＹＥＡＲＳＧＵＷｅｎｓｈｕＡｂｓｔｒａｃｔ：ＴｈｅｒｅｃｏｒｄｅｄｈｙｄｒｏｌｏｇｉｃｄａｔａｏｆｔｈｅＹｅｌｌｏｗＲｉｖｅｒｉｎｄ...