Some relationships between lithology,basin form and hydrology: a case study from the Thames basin,UK

The role of lithology in influencing basin form and function is explored empirically by investigating correlations between a range of catchment variables, where the spatial unit of analysis is not surface catchments but lithologically coherent groundwater units. Using the Thames basin, UK, as a case study, nine groundwater units have been identified. Values for 11 hydrological and geomorphological variables, including rainfall, drainage density, Baseflow Index, aquifer porosity, storage coefficient and log‐hydraulic conductivity, aquifer and drainage elevation, river incision, and hypsometric integral have been estimated for each of the groundwater units in the basin, and Pearson correlation coefficients calculated for all pairs of variables. Seven of the correlation coefficients are found to be significant at a confidence level of > 99%. Negative correlations between drainage density and log aquifer hydraulic conductivity, and between drainage density and river incision, and positive correlations between log‐hydraulic conductivity and river incision, log‐hydraulic conductivity and Baseflow Index, and between Baseflow Index and river incision are inferred to have consistent causal explanations. For example, incision of rivers into aquifers leads to relative increases in hydraulic gradients in the vicinity of rivers which, in turn, promotes the development of secondary porosity increasing both aquifer hydraulic conductivity and, hence, Baseflow Index. The implication of this interpretation is that the geomorphological evolution of basins is intimately linked to the evolution of hydraulic conductivity of the underlying aquifers. This is consistent with, and supports the notion of a coupled complexly evolving surface water‐groundwater system. Copyright © 2011 John Wiley & Sons, Ltd.     

RESPONSE OF SEDIMENT YIELD TO BASIN CHARACTERISTICS IN THE MIDDLE YELLOW RIVER BASIN

1 INTRODUCTION The Middle Yellow River Basin of China is well-known worldwide for its severe soil erosion. The basin extends across arid and desert steppe, semi-arid steppe, and warmly temperate semi-humid forest-steppe from north to south, and morphological characteristics consist of mountains alternating with inter-mountain basins. Landforms change frequently from rocky mountains through rock-loess mixed mountains or hills to loess gullied hills and loess tableland from mountain to bas…     

Temporal variation of river flow renewability in the middle Yellow River and the influencing factors

In the past 30 years, the measured annual river flow of the Yellow River has declined significantly. After adding the diverted water back to get the ‘natural’ annual river flow, the tendency of decrease can still be seen. This indicates that the river flow renewability of the Yellow River has changed. The river flow renewability is indexed as the ratio of annual ‘natural’ river flow to annual precipitation over a river drainage basin, where the ‘natural’ river flow is the measured annual river flow plus the annual ‘net’ water diversion from the river. By using this index, based on the data from the drainage area between Hekouzhen and Longmen stations on the middle Yellow River, a study has been made of the river flow renewability of the Yellow River in the changing environment of the past 50 years. The river flow renewability index (I_rr) in the drainage area between Hekouzhen and Longmen in the middle Yellow River basin has been found to decline significantly with time. In the meantime, annual precipitation decreased, annual air temperature increased, but the area of water and soil conservation measures has been increased. It has been found that I_rr is positively correlated with the areal averaged annual precipitation, but negatively correlated with annual air temperature. There is close, negative correlation between I_rr and the area of water and soil conservation measures including land terracing, tree and grass planting and checkdam building, implying that water and soil conservation measures have reduced the river flow renewability. Copyright © 2005 John Wiley & Sons, Ltd.     

Interpolation of runoff applying objective methods

The paper treats the problem of interpolating annual runoff from regular streamflow measurements in a regional scale applying objective methods. These methods are adapted to point processes like temperature and precipitation. Modifications are needed to account for the fact that streamflow is an integrated process following the hierarchical structure of river systems. The most straightforward method is therefore to relate the interpolation to the existing river network. For theoretical reasons it is preferable to interpolate the lateral inflow rather than the flow in the river itself. Procedures for the interpolation with the different approaches are developed and discussed. Special attention is put on the question how the equation of continuity can be satisfied. The Laagen drainage basin in southern Norway is used as a test area. The data consist of annual observations of streamflow and digital map information on river networks and drainage basin boundaries.     

Interpolation of runoff applying objective methods

The paper treats the problem of interpolating annual runoff from regular streamflow measurements in a regional scale applying objective methods. These methods are adapted to point processes like temperature and precipitation. Modifications are needed to account for the fact that streamflow is an integrated process following the hierarchical structure of river systems. The most straightforward method is therefore to relate the interpolation to the existing river network. For theoretical reasons it is preferable to interpolate the lateral inflow rather than the flow in the river itself. Procedures for the interpolation with the different approaches are developed and discussed. Special attention is put on the question how the equation of continuity can be satisfied. The Laagen drainage basin in southern Norway is used as a test area. The data consist of annual observations of streamflow and digital map information on river networks and drainage basin boundaries.     

Quaternary drainage network reorganization in the Colombian Eastern Cordillera plateau

Dramatic drainage reorganization from initial longitudinal to transversal domains has occurred in the Eastern Cordillera of Colombia. We perform a regional analysis of drainage basin geometry and transformed river profiles based on the integral form of the slope-area scaling, to investigate the dynamic state of drainage networks and to predict the degree of drainage reorganization in this region. We propose a new model of drainage rearrangement for the Eastern Cordillera, based on the analyses of knickpoint distribution, normalized river profiles, landforms characteristic of river capture, erosion rates and palaeodrainage data. We establish that the oldest longitudinal basin captured by the Magdalena River network was the Suárez Basin at ≈409 ka, inferring the timing of abandonment of a river terrace using in situ produced cosmogenic beryllium-10 (¹⁰Be) depth profiles and providing a first estimation of incision rate of 0.07 mm/yr. We integrate published geochronologic data and interpret the last capture of the Sabana de Bogotá, providing a minimum age of the basin opening to the Magdalena drainage at ≈38 ka. Our results suggest that the Magdalena basin Increased its drainage area by integrating the closed basins from the western flank of the Eastern Cordillera. Our study also suggests that the Magdalena basin is an aggressor compared to the basins located in the eastern flank of the orogen and provides a framework for examining drainage reorganization within the Eastern Cordillera and in similar orogenic settings. The results improve our understanding of headward integration of closed basins across orogenic plateaux. © 2020 John Wiley & Sons, Ltd.     

GEOMORPHIC FEATURES OF THE SHULE RIVER DRAINAGE BASIN IN QILIANSHAN AND ITS INSIGHT INTO TECTONIC IMPLICATIONS

Because of the strong uplift of the Qilian Shan since late Cenozoic,the drainage basins that are derived from the mountains have undergone strong tectonic deformation.So the typical geomorphology characteristics of these drainage basins may indicate the strong tectonic movement in the region.For example,the Shule River drainage basin,which originates from the western part of the Qilian Shan owns unique geomorphology characteristics which may indicate the neotectonic movement. Stream networks of the Shule drainage basin extracted from the DEM data based on GIS spatial analysis technology are graded into five levels using Strahler classification method.Four sub-catchments,numbered 1,2,3 and 4 are chosen for detailed analysis.Furthermore,the four sub-catchments,the hypsometric integral curves,Hack profiles,SL index and average slope of the Shule drainage basin are determined by GIS tools.In addition,we analyzed the slope spectrum of the Shule drainage basin. The average elevation of the Shule drainage basin is very high,however,the slope of the drainage basin is very low,the gentle slope occupies so large area proportion that the slope spectrum shows a unimodal pattern and a peak value is in low slope region (0°~5°),so tectonic movement has a strong influence on the drainage basin.Under the intensive impact of the tectonic movement of the active fault and regional uplift,the hypsometric integral curve is sigmoid,revealing that the Shule drainage basin is in the mature stage.The Hack profile is on a convex,the longitudinal profile is best fitted by linear fitting and the abnormal data of the SL index of the Shule River has a good fit with the section through which the active fault traverses,that means the tectonic movement of the active fault has strong influence on the river's SL index.It is worth noting that lithologic factors also have great impact on the river geomorphology in some sections. According to the above analysis,we recognize that in the interior of active orogen,the evolution of river geomorphology usually is influenced by tectonic movement and reveals the regional neotectonics in turn.     

Prediction of daily rainfall state in a river basin using statistical downscaling from GCM output

Conventional statistical downscaling techniques for prediction of multi-site rainfall in a river basin fail to capture the correlation between multiple sites and thus are inadequate to model the variability of rainfall. The present study addresses this problem through representation of the pattern of multi-site rainfall using rainfall state in a river basin. A model based on K-means clustering technique coupled with a supervised data classification technique, namely Classification And Regression Tree (CART), is used for generation of rainfall states from large-scale atmospheric variables in a river basin. The K-means clustering is used to derive the daily rainfall state from the historical daily multi-site rainfall data. The optimum number of clusters in the observed rainfall data is obtained after application of various cluster validity measures to the clustered data. The CART model is then trained to establish relationship between the daily rainfall state of the river basin and the standardized, dimensionally-reduced National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) reanalysis climatic data set. The relationship thus developed is applied to the General Circulation Model (GCM)-simulated, standardized, bias free large-scale climate variables for prediction of rainfall states in future. Comparisons of the number of days falling under different rainfall states for the observed period and the future give the change expected in the river basin due to global warming. The methodology is tested for the Mahanadi river basin in India.     

Statistical Analysis of Water Quality Parameters in Seven Major Serbian Rivers during 2004‒2013 Period

Rivers on territory of the Republic of Serbia can be separated to three sea drainage basins: Black, Adriatic and Aegean. Majority of rivers belong to the Black Sea drainage basin. The Danube is the most important river in Serbia and one of the most important rivers of Europe. All rivers investigated in this paper represent direct or indirect tributaries of the Danube River and as that, they are belonging to the Black Sea drainage basin. In this study, the water quality status and the spatial and temporal trends of seven major rivers in Serbia were assessed through the application of ten parameters of Water Quality Index. Ten year (2004–2013) public database of environmental data was used. Into considerations were taken differences between every river individually and difference between sample positions on every single river. Based on the chemical parameters of water quality, it can be seen that the biggest rivers in Serbia show different values of WQ parameters. The highest WQ value is measured on the Drina River, while the lowest value is measured on the Ju?na Morava and the Tisza River. Analyses of parameters per period of year show that there is a statistically significant difference between values during warm and cold periods.     

Regionalizing mean annual flow and daily flow variability for basin‐scale sediment and nutrient modelling

River discharges vary strongly through time and space, and quantifying this variability is fundamental to understanding and modelling river processes. The river basin is increasingly being used as the unit for natural resource planning and management; to facilitate this, basin‐scale models of material supply and transport are being developed. For many basin‐scale planning activities, detailed rainfall‐runoff modelling is neither necessary nor tractable, and models that capture spatial patterns of material supply and transport averaged over decades are sufficient. Nevertheless, the data to describe the spatial variability of river discharge across large basins for use in such models are often limited, and hence models to predict river discharge at the basin scale are required. We describe models for predicting mean annual flow and a non‐dimensional measure of daily flow variability for every river reach within a drainage network. The models use sparse river gauging data, modelled grid surfaces of mean annual rainfall and mean annual potential evapotranspiration, and a network accumulation algorithm. We demonstrate the parameterization and application of the models using data for the Murrumbidgee basin, in southeast Australia, and describe the use of these predictions in modelling sediment transport through the river network. The regionalizations described contain less uncertainty, and are more sensitive to observed spatial variations in runoff, than regionalizations based on catchment area and rainfall alone. Copyright © 2006 John Wiley & Sons, Ltd.     

Climatic Change and the Dynamics of River Runoff into the Arctic Ocean

Time series of the river runoff into the Arctic Ocean over the period 1921–1999 are obtained through generalization of the available detailed hydrologic data on the drainage basin of the Arctic Ocean and estimates of the river runoff from areas in which no hydrometric observations have been made. Trends in the annual and seasonal river runoff from different parts of the basin are analyzed both for the entire period under study and for the last decades, which in the northern hemisphere are characterized by the most intense rise in air temperature. Potential future changes in the runoff of the main rivers of the basin and in the total river runoff into the ocean are discussed.     

Hydrological behavior of Umshing River,East Khasi Hills,Meghalaya

The morphometric and drainage basin analysis of the Umshing River is carried out quantitatively using remote sensing and GIS techniques. The results are presented concerning the hydrological behavior of Umshing river in order to define multi-scale geomorphometric landform types. The Umshing basin shows a sub-trellis drainage pattern indicating the litho-structural control on the drainage. Lithological, structural and geomorphological features control the directions of flow of the tributaries. It is observed and inferred that the Umshing river catchment is under the stage of creep or tilting and hence is vulnerable to geohazard.     

On the coupled geomorphological and ecohydrological organization of river basins

This paper examines the linkage between the drainage network and the patterns of soil water balance components determined by the organization of vegetation, soils and climate in a semiarid river basin. Research during the last 10 years has conclusively shown an increasing degree of organization and unifying principles behind the structure of the drainage network and the three-dimensional geometry of river basins. This cohesion exists despite the infinite variety of shapes and forms one observes in natural watersheds. What has been relatively unexplored in a quantitative and general manner is the question of whether or not the interaction of vegetation, soils, and climate also display a similar set of unifying characteristics among the very different patterns they presents in river basins. A recently formulated framework for the water balance at the daily level links the observed patterns of basin organization to the soil moisture dynamics. Using available geospatial data, we assign soil, climate, and vegetation properties across the basin and analyze the probabilistic characteristics of steady-state soil moisture distribution. We investigate the presence of organization through the analysis of the spatial patterns of the steady-state soil moisture distribution, as well as in the distribution of observed vegetation patterns, simulated vegetation dynamic water stress and hydrological fluxes such as transpiration. Here we show that the drainage network acts as a template for the organization of both vegetation and hydrological patterns, which exhibit self-affine characteristics in their distribution across the river basin. Our analyses suggest the existence of a balance between the large-scale determinants of vegetation pattern reflecting optimality in the response to water stress and the random small-scale patterns that arise from local factors and ecological legacies such as those caused by dispersal, disturbance, and founder effects.     

Graphical methods of river profile analysis to unravel drainage area change,uplift and erodibility contrasts in the Central Range of Taiwan

To reveal river channel steepness patterns and variance in settings with significant variation in rock uplift rate, rock erodibility and moving water divides, we present a series of graphical methods to interpret channel profiles. To complement Cartesian χ plots, longitudinal profiles and mapping methods, we introduce a new method based on a radial coordinate system. We map each basin onto polar coordinates in which the radial dimension is χ and the azimuthal coordinate, ?, is calculated with an increment (Δ?) scaled to the distance to neighboring channel heads. The elevation is contoured on this mapping. Average channel steepness is estimated by fitting a conical surface to the elevation. The graph simplifies the comparison of χ and elevation between channels that share a divide, and helps identify spatial changes in drainage area and patterns of erodibility. We apply this approach to derive the uplift pattern in the eastern and southern Central Range of Taiwan, where the high tectonic convergence and uplift rates combined with sub‐tropical climate and frequent typhoons results in high exhumation rate, and well‐developed, detachment‐limited river networks. Additionally, the tectonic activity leads to drainage basin reorganization. We identify examples of divide migration, discrete river capture as well as anomalous steepness that we attribute to local variability in rock erodibility. Estimated basin‐average steepness values show the highest and a near constant value from Hsinwulu basin to Liwu basin in the center of the Island. To the north and south of this region, the values gradually decrease. These estimates show good correlation with the topography of the Central Range and erosion rates derived from in situ ¹⁰Be concentrations in river‐borne quartz. We conclude that the basin steepness reflects systematic differences in rock uplift rate and erosion rate. Copyright © 2016 John Wiley & Sons, Ltd.     

A BRIEF INTRODUCTION TO THE NEW METHOD FOR RIVER PROFILE ANALYSIS: Integral Approach

The topography and geomorphology of active orogens result from the interaction of tectonics and climate. In most orogens, a fluvial channel is most sensitive to the coupling between tectonics, lithology, and climate. Meanwhile, the related signals have been recorded by both the drainage geometry and channel longitudinal profile. Thus, how to extract tectonic information from fluvial channels has been a focused issue in geologic and geomorphologic studies. The well known stream-power river incision model bridges the gap between tectonic uplift, river incision and channel profile change, making it possible to retrieve rock uplift pattern from river profiles. In this model, the river incision rate depends on the rock erodibility, contributing drainage area and river gradient. The steady-state form of the river incision model predicts a power-law scaling between the drainage area and channel gradient. Via a linear regression to the log-transformed slope-area data, the slope and intercept are channel concavity and steepness indices, respectively. The concavity relates to lithology, climatic setting and incision process while the channel steepness can be used to map the spatial pattern of rock uplift. For its simple calculation process, the slope-area analysis has been widely used in the study of tectonic geomorphology during past decades. However, to calculate river slope, the coarse channel elevation data must be smoothed, re-sampled, and differentiated without any reasonable smooth window or rigid mathematical fundamentals. One may lose important information and derive stream-power parameters with high uncertainties. In this paper, we introduce the integral approach, a procedure that has been widely used in the latest four years and demonstrated to be a better method for river profile analysis than the traditional slope-area analysis. Via the integration to the steady-state form of the stream-power river incision equation, the river longitudinal profile can be converted into a straight line of which the independent variable is the integral quantity χ with the unit of distance and the dependent variable is the relative channel elevation. We can calculate the linear correlation coefficient between elevation and χ based on a series of concavity values and find the best linear fit to be the reasonable channel concavity index. The slope of the linear fit to the χ value and elevation is simply related to the ratio of the uplift rate to the erodibility. Without calculating channel slope, the integral approach makes up for the drawback of the slope-area analysis. Meanwhile, via the integral approach, a steady-state river profile can be expressed as a continuous function, which can provide theoretical principle for some geomorphic parameters (e.g., slope-length index, hypsometric integral). In addition, we can determine the drainage network migration direction using this method. Therefore, the integral approach can be used as a better method for tectonogeomorphic research.     

基于连通性指数(IC)的近30年鄱阳湖流域水系结构与水文连通演变评估

由于气候变化和人类活动等多重影响,流域河湖水系格局与连通程度发生了显著变化,进而引发洪涝灾害等一系列水资源问题。本文以鄱阳湖流域为研究区,基于Google Earth Engine(GEE)提取1989—2020年5期水系数据,采用图论方法构建水系评价体系,定量分析该地区近30年来水系格局和结构连通性的时空演变特征,并结合该时期地形、土地利用和归一化植被指数(NDVI)等数据,利用连通性指数(index of connectivity,IC)评估功能连通性的动态变化,进而探讨水文连通与径流量和输沙量的联系。结果表明,近30年来鄱阳湖流域水系结构趋于复杂化,主要体现在流域北部。除干流外,其他等级河流的数量和长度均有所增加,其中Ⅲ级河流最为明显。河网密度、水面率、河网复杂度和发育系数均呈增加趋势,2000年后的变化率约为2000年前的两倍。水系连通环度、节点连接率和水系连通度总体增加,结构连通性呈好转趋势且变化幅度较小。功能连通分析表明,近30年来大部分流域IC减少,流域下游靠近主河道的平坦地区IC较高,上游远离河道的植被密集区域IC较低。此外,IC与年径流量和输沙量表现为显著的正相关性(...     

Analytical model for a geomorphological instantaneous unit hydrograph

The rainfall‐runoff modelling of a river basin can be divided into two processes: the production function and the transfer function. The production function determines the proportion of gross rainfall actually involved in the runoff. The transfer function spreads the net rainfall over time and space in the river basin. Such a transfer function can be modelled using the approach of the geomorphological instantaneous unit hydrograph (GIUH). The effectiveness of geomorphological models is actually revealed in rainfall‐runoff modelling, where hydrologic data are desperately lacking, just as in ungauged basins. These models make it possible to forecast the hydrograph shape and runoff variation versus time at the basin outlet. This article is an introduction to a new GIUH model that proves to be simple and analytical. Its geomorphological parameters are easily available on a map or from a digital elevation model. This model is based on general hypotheses on symmetry that provide it with multiscale versatile characteristics. After having validated the model in river basins of very different nature and size, we present an application of this model for rainfall‐runoff modelling. Since parameters are determined relying on real geomorphological data, no calibration is necessary, and it is then possible to carry out rainfall‐runoff simulations in ungauged river basins. Copyright © 2006 John Wiley & Sons, Ltd.     

TOPMODEL在珠江流域布柳河流域的应用及其与新安江模型的比较

TOPMODEL是一种以地形为基础的半分布式流域水文模型.对珠江流域布柳河流域的DEM信息进行处理,提取流域的水系、子流域边界、地形指数及水流路径距离的分布,将TOPMODEL应用于该流域中.另外将新安江模型也应用于该流域进行比较.此外,分析了两种模型结构差异所带来的模拟功能差异.两种模型模拟结果精度差异不大,而TOPMODEL实现了空间产流面积分布的可视化.     

The declining but non-rejuvenating base level—The Lisan lake,the Dead Sea area,Israel

Laboratory experiments investigating the effects of a lowering base level do not simulate natural eustatic lowering along concave river profiles. The field data on this issue are also quite limited. In evaluating the control exercised by lowering base level on a drainage network, distinction must be made between its influence and those of other hydromorphological processes operating within the basin. Field data on morphological relations, based on photogrammetric mapping and longitudinal profiling, have been gathered in the Dead Sea area, Israel, where a rapid fall in base level has occurred during the Holocene. The study area is an entrenched fan delta with a sequence of 14 unpaired fan terraces which die out at intersection points within an alluvial fan system. The results suggest that the intersection points did not function as base levels. The receding base level played only a passive role, allowing entrenchment without transmitting a head-cutting feedback basinwards. The arid environment caused a delay in transmission of information through the system. The results support the model of short, episodic, and discontinuous erosional events, inherent in the evolution of drainage basins. It is suggested that base level effects in temperate and humid regions are not transferrable to arid zones.     

Forecasting changes of water resources in large rivers following land drainage / Méthode de prévision des modifications des ressources en eau des grands fleuves sous l'effet du drainage

ABSTRACT

Techniques are described for annual forecasts of the water balance after drainage of large river basins. In the development of these techniques precipitation was assumed to be constant and unaffected by drainage. It is shown that the effect of drainage upon the annual runoff of the improved basins is to decrease the groundwater and swamp water resources which leads to evaporation changes. According to experimental data on the hydrophysical properties of peats, mineral soils and subsoils and how they change after drainage, the decrease in the groundwater resources was estimated for each per cent of the basin drained. This allowed account to betaken of this effect while making forecasts of runoff changes. Evaporation changes are computed as the difference between the maximum possible evaporation (potential evaporation) from cultivated areas and that from undisturbed swamps.