Basin Characteristics Research Articles

Improving the flood prediction capability of the Xin’anjiang model by formulating a new physics-based routing framework and a key routing parameter estimation method

The well-known conceptual Xin'anjiang model (XAJ) has limited capability for application in the basins with limited data due to two major runoff routing problems: relying on the observed flow data to estimate the parameters of the Muskingum method and lack of physics-based representation of spatial heterogeneity in key routing parameters such as the river network recession constant (Cs). To tackle these issues, this study first developed a new hybrid rainfall-runoff model named the Xin’anjiang Digital CHannel (XAJ-DCH) model by coupling the XAJ model with the Muskingum-Cunge-Todini (MCT) and diffusion wave methods to improve the river network routing. Then a physics-based Cs estimation method was developed to conquer the data limitation by deriving the quantitative relationships of the Cs parameter with basin characteristics such as sub-catchment area, average river slope, average rainfall intensity, and average river width based on the mass conservation. The flood prediction capabilities of the XAJ and XAJ-DCH models were further tested and compared in the Tunxi Catchment with two nested sub-catchments. The results show that the XAJ-DCH model can predict stream flows well at both catchment outlet and internal channel grid cells without recalibration. Moreover, the derived Cs values based on the proposed method enable both XAJ and XAJ-DCH models to gain good results with the averaged Nash-Sutcliffe efficiency ranging between 0.91 and 0.95.

Regional relationships for bankfull hydraulic geometry and discharge in the southern Andes of Ecuador: An application in the estimation of geomorphological runoff thresholds

The bankfull represents the boundary between the processes taking place in the canal and the floodplain. The geometry of the bankfull is highly correlated with the drainage area, making it possible to establish regional bankfull geometry relationships that have wide application in canal restoration, studies of river bed degradation, dimensioning of infrastructure, hydrological modeling, among others. In this study, the regional bankfull geometry relationships were determined for an Andean zone in southern Ecuador, getting coefficients comparable to those reported in literature determined in other mountainous areas of the continent. Correlation coefficients higher than 0.60 were obtained, considered statistically significant. The geomorphological runoff threshold, which represents the effective amount of rainfall needed to produce bankfull discharges, was determined using regional bankfull geometry relationships, geomorphological characteristics of the drainage basins in the study area, and the NRCS unit hydrograph. The geomorphological runoff threshold varies from 0.8 mm to 8.50 mm and is based on the concept of the unit hydrograph; therefore it presents the same application limitations and uncertainties associated with the determination of the characteristics of the basin, the bankfull and the scale of work. Future works are proposed considering more detailed scales, a greater number of observation sites and the inclusion of additional variables of the drainage area such as slope, aspect and precipitation, to improve the estimates.

Integrating IHACRES with a data-driven model to investigate the possibility of improving monthly flow estimates

Abstract Estimating the outflow of basins is a critical step in surface water resources planning and management, especially in basins that lack reliable long-term observed data of streamflow. Hydrological models, which can simulate the process of rainfall-runoff, can be used to obtain reliable estimates of streamflow from precipitation data and the physical characteristics of basins. The focus of the present study was to estimate the outflow of 19 sub-basins located in Guilan Province, northern Iran. To achieve this, hybrid models were developed by integrating the IHACRES (identification of unit hydrograph and component flows from rainfall, evapotranspiration, and streamflow) hydrological model with the intelligent-based GMDH (group method of data handling) model. The IHACRES model was calibrated using monthly ground-based precipitation and temperature data as well as satellite-based precipitation data. The lowest and highest Nash-Sutcliffe coefficient (NS) for the IHACRES models were, respectively, 0.14 and 0.68 in the calibration phase and 0.11 and 0.73 in the validation phase. It was also observed that using satellite-based precipitation data reduces NS by 10–75% in the 19 sub-basins under study. After calibrating and validating the IHACRES models, the hybrid models were developed by integrating IHACRES and GMDH models. The lowest and highest NS for the hybrid models were, respectively, 0.23 and 0.81 in the calibration phase and 0.11 and 0.81 in the validation phase. It was observed that, on average, integrating IHACRES and GMDH increases the NS by 44.1% in the calibration phase and 37.0% in the validation phase in comparison with the IHACRES model. According to the NS, the hybrid model had ‘acceptable’ performance in six sub-basins in which the IHCRES model had ‘unacceptable’ performance. It was observed that integrating the IHACRES model with a data-driven model (the GMDH model) can generally improve the simulation results in all sub-basins under study.

Quantitative evaluation of drainage attributes to infer hydrologic and morphological characteristics of upper Beas Basin, Himachal Pradesh: A GIS-based approach

ABSTRACT Drainage morphometric analysis is a quantitative indexing of linear, areal, and relief attributes of a watershed, which is an essential prerequisite to understand the ongoing geomorphological, geological, and tectonic processes in a watershed that modifies its landscape. The present study is an investigation of the morphometric parameters of upper Beas basin. ALOS PALSAR digital elevation model available at 12.5 m resolution from Alaska Satellite Facility has been used for the study in Arc GIS 10.2 environment. The findings of the study categorize upper Beas as a sixth order drainage basin with a total area of 4958.98 km2. High bifurcation values infer an accelerated state of erosion and underline the mountainous origin and late youthful stage of river Beas and its tributaries. Geometrically, the basin has an elongated shape indicating lower peak flow but for a longer duration making flood management ambiguous. Upper Beas basin has a coarse drainage density and texture, suggesting high infiltration and less surface water availability. Tectonically, studyarea has some prominent faults and thrusts (MBT, MCT, and STD), making the region susceptible to water infiltration. These observations unquestionably indicate a strong tectonic and lithological control over the evolution of drainage patterns in the study area.

Diagnosis of eco-environmental quality in the Keluke Lake basin, China

In order to clarify the eco-environmental quality and its evolution characteristics of Keluke Lake basin, we selected 15 factors of physical geography, meteorology, land use/cover and social economy using comprehensive investigation, remote sensing interpretation and inversion, statistical analysis and other technical means, based on the relevant theories of environmental ecology. We used factor analysis and entropy method to calculate the index weight, constructed watershed soil quality model and ecological environment quality diagnosis model, and analyzed the changes of soil and eco-environmental quality in the Keluke Lake basin in 2000, 2005, 2010 and 2015. The results showed that the average eco-environmental quality in four periods was 21, 47, 54, and 72, showing a stable upward trend. The eco-environmental quality level changed from poor to good, while soil quality was at the middle level. Spatially, the eco-environmental quality of the northern mountainous area, the downstream wetland and the surrounding area of the river improved significantly. The change of eco-environmental quality was a result of human activities and natural factors. Soil quality and lake area were key factors indicating the eco-environment of the Keluke Lake basin. The minimum ecological water demand of the Keluke Lake was the basic guarantee to maintain the benign development of the eco-environment of the lake basin.

Application of GIS techniques to understand the geomorphometric characteristics of a tropical watershed in South India

ABSTRACT Identifying and protecting natural resources is a meaningful way forward for achieving sustainable development. Since water is a precious natural resource that is being depleted faster than it is recharged, there is an urgent need to evaluate and monitor this resource. Watershed-based studies are gaining momentum, while studying about the natural resources. The purpose of this study is to analyze the morphometric characteristics of a watershed. Numerous morphometric parameters have been devised by various scholars to measure the drainage basin characteristics quantitatively. The methodology of this study is to make use of remote sensing and GIS techniques to analyze the drainage morphometry of Vannathangarai watershed in Tamil Nadu, India. The study has identified that the watershed has a low runoff and slow infiltration, thus pointing toward a probability of flooding. The study also revealed that the basin is well drained, basin where the surface is lowered by erosion.

Characteristics of deep geological structure and petroleum exploration prospectin Turpan-Hami Basin

Characteristics of deep geological structure and petroleum exploration prospectin Turpan-Hami Basin

Analysis about the impacts of changing basin underlying surface on design floods for design units of water diversion projects

After the water diversion project has been put into operation for many years, due to the long distance, complex hydro-meteorological conditions, and rapid development of social economy, the underlying surface conditions of corresponding natural basins in the design units of water diversion project have changed to some extent compared with the beginning of the project design, especially the underlying surface situation of rivers in the northern region has changed greatly. Based on ArcGIS to extract basin characteristic values of the design unit of water diversion project, such as basin area, river length and slope, this paper analyzes the changes of current basin characteristic values of design unit compared with the design period. For the design unit with significant changes in the basin characteristics, the original design flood calculation method is used to calculate the flood of the same design rainstorm under current conditions, and the impacts of changing basin underlying surface on design floods are analyzed. PACS: J0101

Calidad del agua y niveles guía para la protección de la biodiversidad acuática. Interacción entre ciencia y gestión

Argentina has a great diversity of aquatic environments associated with the variety of climatic regions that determine unique characteristics of hydrological basins. This diversity is given by morphological conditions, physicochemical characteristics and the presence of natural and xenobiotic substances derived from anthropic activity. The toxicity of different substances on aquatic biota produces modifications in the quality of the aquatic systems. To maintain the benefits and services that the ecosystems offer, a long time effective management based on its integral management is necessary. Strategies for protection of aquatic biodiversity demand definition of guide levels (NG) for water quality. According to the environmental policy of Argentina, those who manage the water resource consider the NG of water quality as a reference framework for the definition of its aptitude in relation to their uses. The definition of NG is among the incumbencies of the hydrological national authority. With this objective, the Ministry of Environment and Sustainable Development (MAyDS) was linked with the National Scientific and Technical Research Council - Argentina (CONICET) to work in the water quality and to establish NG for the protection of aquatic biodiversity (NG-PBA). Considering the demand from the government sector, the aims of this work were: to obtain a robust methodology that allows determining NG-PBA, to establish criteria for selection and prioritization of substances, and to discuss the regional adaptation of the NG-PBA. The agreed methodology was based on the NG-PBA previously developed by the ex- Secretary of Water Resources (SSRH), updated in terms of the operative sequences, statistic method, and amount and prioritization of species. A preliminary list of substances for which establishing the corresponding NG to derivate was determined. It was recognized the interaction between scientific knowledge and management of natural resources as a synergic tool, and as superlative mechanism for the protection of aquatic biodiversity.

ASSESSMENT OF FLUORIDE CONTENT IN THE RIVER WATER UZH AND LATORITSIA

The fluoride content in the waters of the Uzh and Latorytsia rivers was assessed (2020, all seasons). The basins of the studied rivers have complex tectonics and geology. It was found that the total content of fluorides in the water of the Uzh River is low (23.7-61.5 μg×L-1) and relatively stable over time. There are no natural and anthropogenic sources of fluoride pollution of river water. Variation of the total content of fluorides in water downstream occurs due to the geochemical characteristics of the river basin. The highest fluoride content is observed near the Uzhhorod city. It is shown that the content of biologically available forms (not chemically bonded) of fluorides in the water of the Uzh River is extremely low (2.2-4.8 μg×L-1). This can lead to fluoride deficiency in the region's residents, who use the Uzh River water as a source of drinking water.
 The total content of fluorides in the water of the Latorytsia River varies between 31.4-67.6 μg×L-1, which is to some extent comparable to the content in the Uzh River. Variation of fluoride content along the river is due to the geochemical characteristics of the river basin, the highest fluoride content in the water of the Latorytsia River is observed near Mukachevo city. It was also found that the content of biologically available forms of fluorides in the water of the Latorytsia River is extremely low (2.9-5.6 μg×L-1). Therefore, if the residents of the region use the water of the Latorytsia River as a source of drinking water, fluoride deficiency is possible. In general, the content of fluorides in the river waters of the Transcarpathian region is relatively low. The results of the research will be used for the planning the diet of residents of these regions of Transcarpathia.

Morfometría de la microcuenca quebrada El Estero, San Ramón, Alajuela, Costa Rica

This research analyses some morphometric characteristics of a small basin called El Estero. The form, relief and drainage associated with the morphodynamics of the micro basin are analyzed. For the development of the research, topographic maps 1: 50 000 scale, GIS and the Excel program were used to calculate data. The objective was to know the morphometry of the stream, since it has caused several floods. For tis purpose, some basic measurements were calculated (surface, shape, microbasin length, channels, elevation, elevation of the main channel and number of lower-order channels). The basin in its upper part is characterized by a deeper V-shaped channel, with some presence of vegetable riparia, although there are certain erosive processes. The middle part is characterized by being located a city on a corrugated surface, the flow level is higher, and the series of sewers cause chaotic accumulations (plugs) and damage to the existing infrastructure, through flooding mainly during intense rainy events. The lower part of the micro-basin has a tectonic fault, characteristic for presenting a jump or cataract and in its margins strong erosive and sliding.

Climate variables on the hydrographic basin of Uruçuí Preto River – Piauí, Brazil subsidies for the management of water and agricultural resources

The knowledge of the climatic characteristics of the hydrographic basins, especially regarding the temporal and spatial distribution of rainfall, the relative humidity of the air and the maximum, minimum and average temperatures of the air, which offer important subsidies to the management of water resources and agriculture. The irregular distribution of rainfall indicates instability in the entry of water into the hydrological system, exercising control over water availability in time and space, the relative humidity of the air influences animal and plant behaviors and the amount of water available in the atmosphere. The temperature, on the other hand, influences the evapotranspiration rates, indicating the energy availability of the environment and, consequently, the environmental water demand. The work presents characteristics of the hydrographic basin of the Uruçuí Preto River (BHRUP), in terms of rainfall, relative humidity, temperature, climatological water balance and climatic regimes. The graphs of annual behavior and seasonal regimes elaborated for 25 pluviometric stations distributed in the interior and around the basin, most of them in operation since the 1960s, followed by the elaboration of average isoietas charts and the one of the rainiest semester, relative humidity of the air, isotherms of the maximum, minimum and average temperatures, and of the letters of potential evapotranspiration, real evaporation and water deficit. The climatic types were appreciated due to the influence of the habitual behavior of the atmosphere on the potential and real environmental demand for water and also on the anthropic demand. The Thornthwaite (1948, 1953) climate system was used, based on the comparison between potential evapotranspiration and rainfall.

Modeling the Hydrological Impacts of Vegetation Cover Changes in the Upper Oum Er-Rbia Watershed (Morocco)

In Morocco, the mountainous areas are often exposed to bulky and vicious flows of water and sediment. This process is exacerbated by the decrease in vegetation cover and the disruption in rainfall-runoff conditions that frequently cause significant flooding. By exploring the main hydrologic elements of these processes, it is possible to understand the behavior and hydrological response of watersheds and thus plan accordingly. In this study, the authors focused on determining the morphometric characteristics of the upper Oum Er-Rbia River basin (UOERRB by assessing/ evaluating the land use and land cover changes for a period of 32 years (1984–2016). Hydrologic Engineering Center’s Hydrologic Modeling System (HEC-HMS) was applied to simulate four daily hydrological events. The concentration time was 7.7 hours. The four storm events examined to calibrate and validate the simulated outflow at the outlet indicated a good agreement between the hydrographs of the measured and simulated flows, with an average Nash-Sutcliffe efficiency (NSE) value ranging from 0.63 to 0.76. Between 2002 and 2016, an average 6.21 percent increase in vegetation cover of with annual rainfall increasing from 690 to 714.1 mm/year was observed. These results can contribute to a better understanding of the hydrologic processes and better estimation of the return flows and thus guiding management decisions and developments in the UOERRB.

Morphometric Characteristics Of Al-Ratqa Valley Basin In The Western Anbar Plateau

Al-Ratqa Valley is located in the western part of Iraq within the western Anbar plateau, and it occupies an area of (5509) km2, and it consists of six secondary basins and they differ in all morphometric characteristics. The study also included the natural characteristics of the area that have an effect on the spatial and morphological characteristics and the characteristics of the drainage pattern. And the geomorphological processes and the types of soils in the region, as for the general slope of the basin, it is from the west and southwest towards the east and northeast, as for the general climate of the region, it is desert, hot dry in summer and cold rainy in winter, and the number of basin ranks reached seven ranks, and that the quantitative method was followed in the geomorphological and morphometric analysis By relying on digital data obtained from topographic maps, aerial photos and satellite lmages, in the analysis of the morphometric characteristics of the basin drainage pattern and the spatial, morphological and topographic characteristics of Al-ratqa Valley basin

Formation of overpressure system and its relationship with the distribution of large gas fields in typical foreland basins in central and western China

Based on the data of measured formation pressure, drilling fluid density of key exploration wells and calculated pressure by well logging, combined with the analysis of natural gas geological conditions, the characteristics and formation mechanisms of formation fluid overpressure systems in different foreland basins and the relationship between overpressure systems and large-scale gas accumulation are discussed. (1) The formation mechanisms of formation overpressure in different foreland basins are different. The formation mechanism of overpressure in the Kuqa foreland basin is mainly the overpressure sealing of plastic salt gypsum layer and hydrocarbon generation pressurization in deep–ultra-deep layers, that in the southern Junggar foreland basin is mainly hydrocarbon generation pressurization and under-compaction sealing, and that in the western Sichuan foreland basin is mainly hydrocarbon generation pressurization and paleo-fluid overpressure residual. (2) There are three common characteristics in foreland basins, i.e. superimposed development of multi-type overpressure and multi-layer overpressure, strong–extremely strong overpressure developed in a closed foreland thrust belt, and strong–extremely strong overpressure developed in a deep foreland uplift area. (3) There are four regional overpressure sealing and storage mechanisms, which play an important role in controlling large gas fields, such as the overpressure of plastic salt gypsum layer, the overpressure formed by hydrocarbon generation pressurization, the residual overpressure after Himalayan uplift and denudation, and the under-compaction overpressure. (4) Regional overpressure is an important guarantee for forming large gas fields, the sufficient gas source, large-scale reservoir and trap development in overpressure system are the basic conditions for forming large gas fields, and the overpressure system is conducive to forming deep to ultra-deep large gas fields.

Sandstone reservoir characteristics of Rio Del Rey basin, Cameroon, using well-logging analysis

The present work deals with an interpretation of well log data (gamma ray (GR), resistivity, density, and neutron) from four wells, namely P-1, P-2, P-3 and P-4 in the study area of the Rio Del Rey basin. The well logs analysis indicates five potential sandstone reservoirs at the P-1, two at the P-2, four at the P-3 and six at the P-4. The neutron–density-GR logs highlight the sandstone gas reservoir characterized by high resistivity and crossover between neutron density. The neutron–density-GR cross-plot confirms the presence of sandstone containing hydrocarbons by a displacement of the cloud of points, from low to medium GR values, from the sandstone line to the left. Petrophysical parameters exhibit the value 12–41% for a volume of shale, 15–34% for effective porosity, 29–278 mD for permeability and 3–63% for water saturation. The three potential hydrocarbon reservoir saturation ranges from 22 to 45%. The study will contribute to future offshore oil and gas exploration and development in the Rio Del Rey basin, based on the geological and geophysical characteristics of the reservoirs delineated.

Shifts in hydroclimatology of US megaregions in response to climate change

Most of the population and economic growth in the United States occurs in megaregions as the clustered metropolitan areas, whereas climate change may amplify negative impacts on water and natural resources. This study assesses shifts in regional hydroclimatology of fourteen US megaregions in response to climate change over the 21st century. Hydroclimatic projections were simulated using the Variable Infiltration Capacity (VIC) model driven by three downscaled climate models from the Multivariate Adaptive Constructed Analogs (MACA) dataset to cover driest to wettest future conditions in the conterminous United States (CONUS). Shifts in the regional hydroclimatolgy and basin characteristics of US megaregions were represented as a combination of changes in the aridity and evaporative indices using the Budyko framework and Fu’s equation. Changes in the climate types of US megaregions were estimated using the Fine Gaussian Support Vector Machine (SVM) method. The results indicate that Los Angeles, San Diego, and San Francisco are more likely to experience less arid conditions with some shifts from Continental to Temperate climate type while the hydroclimatology of Houston may become drier with some shifts from Temperate to Continental climate type. Additionally, water yield is likely to decrease in Seattle. Change in the hydroclimatology of Denver and Phoenix highly depends on the selected climate model. However, the basin characteristics of Phoenix have the highest sensitivity to climate change. Overall, the hydroclimatic conditions of Los Angeles, San Diego, Phoenix, Denver, and Houston have the highest sensitivity to climate change. Understanding of future shifts in hydroclimatology of megaregions can help decision-makers to attenuate negative consequences by implementing appropriate adaptation strategies, particularly in the water-scare megaregions.

Morphometric properties of river basins as indicators of relative tectonic activity – Problems of data handling and interpretation

Morphometric properties of drainage basins, expressed as indices related to their shapes, altitude variability, river networks and stream profiles, are frequently used as proxy information concerning the relative intensity of uplift. Research procedures lead towards division of an area into classes of relative tectonic activity (various rates of surface uplift) and are typically based on compound indices that jointly consider various individual parameters. Given that index approaches are quantitative in nature and comprise large sets of data, their statistical treatment should become an inherent component of the workflow, whereby the results of the statistical analyses should guide the conclusions. However, various data handling issues seem to be seldom addressed or are given inadequate attention. They include selection of variables, correlation analysis, principles of classification in terms of relative tectonic activity, validity of classifications, and criteria for using specific statistical procedures. In this paper we demonstrate the need for rigorous statistical data analysis in a morphometric study, focused on an intraplate mountainous terrain in Central Europe (Orlickie-Bystrzyckie Mountains Block), subject to low or moderate uplift. We analysed 56 drainage basins within the footwall blocks of several prominent fault-generated escarpments. Following literature guidance, the hypsometric and shape characteristics of the drainage basins were considered, whereas clustering and pure-rank based approaches were tested to distinguish classes of relative tectonic activity. The results were compared with indicators of tectonic activity calculated for the escarpments themselves and using DEM-derived terrain attributes indicating enhanced erosion. In addition, we used statistical tests to identify possible lithological influence on the variability of morphometric parameters, which in this study was found to be of secondary importance. Statistical considerations neither allowed for unequivocal classification of drainage basins in terms of relative tectonic activity, nor did they reveal a clear spatial distribution pattern of drainage basins with different morphometric characteristics, typically considered to reflect tectonic forcing. Thus, statistics-based analysis is recommended to avoid the risk of over-interpretation. It is also possible that the likely morphometric signature of tectonically less active settings comprises spatially inconsistent information rather than it is typified by consistently low values of various morphometric parameters.

Multifractal Characteristics Analysis Based on Slope Distribution Probability in the Yellow River Basin, China

Multifractal theory provides a reliable method for the scientific quantification of the geomorphological features of basins. However, most of the existing research has investigated small and medium-sized basins rather than complex and large basins. In this study, the Yellow River Basin and its sub-basins were selected as the research areas, and the generalized fractal dimension and multifractal spectrum were computed and analyzed with a multifractal technique based on the slope distribution probability. The results showed that the Yellow River Basin and its sub-basins exhibit clear multifractal characteristics, which indicates that the multifractal theory can be applied well to the analysis of large-scale basin geomorphological features. We also concluded that the region with the most uneven terrain is the Yellow River Downstream Basin with the “overhanging river”, followed by the Weihe River Basin, the Yellow River Mainstream Basin, and the Fenhe River Basin. Multifractal analysis can reflect the geomorphological feature information of the basins comprehensively with the generalized fractal dimension and the multifractal spectrum. There is a strong correlation between some common topographic parameters and multifractal parameters, and the correlation coefficients between them are greater than 0.8. The results provide a scientific basis for analyzing the geomorphic characteristics of large-scale basins and for the further research of the morphogenesis of the forms.

Integrating Regional Frameworks and Local Variability for Riverine Bioassessment.

Regional frameworks enable bioassessment methods to detect anthropogenic effects on ecosystems amid natural variability. Conventional approaches to regionalization have used coarse geographical frameworks to separate sites similar in their ecological (ecoregion) or faunal (basin) characteristics. Expectations for individual streams are then adjusted for within-region variability in local environmental characteristics. Integrating regional frameworks and local variability may improve the sensitivity and performance of bioassessments. In this study, we used a biologically-informed stream classification to develop an integrated regional framework for bioassessment considering the effects of ecoregion, basin, and local environmental variables on wadeable stream fish communities of South Carolina, USA. Our integrated framework was compared against conventional regional frameworks indexing ecoregions or basins alone. Frameworks were evaluated by their ability to (1) efficiently partition community variation and (2) allow for the detection of anthropogenic effects on fish communities. We found an integrated framework better described natural variability in stream fish communities. In addition, we found highly regional relationships between fish metrics and anthropogenic disturbance among frameworks, suggesting appropriate bioassessment metrics will differ across regions in our study area. Differences in community response to disturbance among frameworks emphasize the importance of testing metrics for their hypothesized sensitivity before using them in bioassessment. This study ultimately supports the integration of regional frameworks across spatial scales to classify streams for bioassessment, and provides an analytical framework from which to evaluate biotic variation and metric utility in the context of bioassessment.