River Basin Boundaries Research Articles

Exploring the Spatial Distribution of Coastal Drainage Basins in Turkey

Coastal regions are vital areas globally, serving as hubs for human habitation and economic activities. Water, being the fundamental resource for life, plays a crucial role in sustaining ecosystems and shaping coastal landscapes. The convergence of river systems in coastal zones underscores their significance in the hydrological cycle and aquatic biodiversity. However, managing these valuable yet vulnerable regions presents multifaceted challenges, necessitating robust management frameworks supported by monitoring and assessment tools. In Türkiye, a country with limited freshwater resources, the management of coastal zones is particularly complex due to increasing pressure on resources and land. This study examines the distribution and characteristics of river and coastal basins in Türkiye. Through spatial analyses on Geographical Information System and basin delineations with watershed modelling program, the study clarifies the regional differences and obstacles encountered by coastal provinces spanning the entirety of Türkiye's coastal borders. The results offer valuable understanding regarding the spatial dynamics of Türkiye's coastal areas with particular emphasis on the significance of Black Sea coastal basins and all coastal provinces. Firstly, river basin systems draining into the Black Sea constitute the majority of Türkiye's surface area. Although the Black Sea region covers only 14% of the total area, more than half of the country's surface area, excluding transboundary and endorheic basins, drains into the Black Sea. Similarly, the analysis of basin types reveals that coastal basins constitute approximately 18% of the drainage areas associated with our coastal waters, nearly one-fifth. This distinction between coastal basin and river basin boundaries differs from the traditional zoning approach in river basin management and coastal area management plans in Türkiye. Consequently, it is anticipated that this spatial evaluation, which has brought a new perspective, will significantly contribute to addressing management challenges, especially the studies that will be evaluated together with population and resource use.

Automation of determining the boundaries of river basins of small rivers: the case of Khangalassky district of the Sakha Republic (Yakutia)

Currently, the absence of a GIS system linked to river basins in Russia may complicate the work of important operational environmental and hydrometeorological surveillance services. It is important to note that simplifying and accelerating the allocation of river basins through open source software can significantly optimize the work of researchers, especially in conditions where it is important to respond promptly to floods and floods in a short time. The purpose of this work is to automate the allocation of river catchment areas, which can help in the study of vast territories of the Far East, as well as contribute to the creation of effective forecasting and monitoring systems. The study presents an automated approach to the identification of watersheds based on the use of geospatial data and information processing algorithms. The presented method demonstrates the effective allocation of watershed boundaries, which makes it possible to simplify the research process and increase the accuracy of the data obtained. The study was conducted within the boundaries of Khangalassky district of the SR(Ya). The data obtained using digital terrain models were corrected, and then used for rapid allocation of watersheds by means of an algorithm developed by the authors. The algorithm is a module for QGIS, which uses the QGIS and GDAL tools in turn, which significantly speeds up the process of creating materials for further research. The results of the study emphasize the accessibility of obtaining information about the geosystems of river basins as integral systems and put forward the prospect of improving GIS processes related to water resources for more effective monitoring of ecosystems and decision-making in the field of environmental protection.

Morphometric delineation of administrative boundaries and classification of threatened categories of small watersheds in transboundary rivers

The ecological conservation of large rivers is impossible unless immediate attention is given to protecting their small tributaries at local levels. The natural boundaries of large river basins are shrinking because their tributaries and streams of different orders are disappearing at an unprecedented rate. Delineation of the fixed administrative boundaries (AB) to protect the natural boundary of small rivers and their classification into appropriate threatened categories, the present study was carried out on the 54.08 km long Banki River in the Ganga River basin. The > 70% irreversible loss in the number of streams (Nu), length of streams (Lu), and drainage density (Dd) resulted in the conversion of the 6th order Banki into the 4th order river. The extreme morphometric changes result in the Banki watershed being under the “Critically Endangered” category. The drainage density ratio (DdR) and mean stream width (Msw) were used to determine the width of AB (WAB). The “River Red List Categories and Criteria” are being proposed to strengthen global initiatives at the local levels to protect and conserve inland water bodies and transboundary rivers.

The Erosional Signature of Drainage Divide Motion Along the Blue Ridge Escarpment

AbstractThe planform rearrangement of river basins is recognized as an important process for landscape evolution. The boundaries of river basins can shift either through gradual drainage divide migration or discrete river captures, but the methods for identifying these processes often rely on topographic evidence that remains otherwise untested. Moreover, efforts to understand the relative importance of either process are hampered by a lack of age constraints on river captures. We use 10Be‐derived erosion rates to test whether, and how, divide motion is occurring at three locations along the Blue Ridge Escarpment in the Appalachian Mountains. In the Pee Dee River basin, we find that the escarpment is migrating inland up to 45 m/Myr, consistent with topographic evidence for gradual divide migration. In the Dan River basin, erosion rates support the topographic evidence for river capture, and we use a forward model of river incision to estimate that the capture likely occurred in the past 12.5 Myr. In the South Fork Roanoke River basin, where the presence of a knickzone has been interpreted as evidence that a river capture initiated a pulse of faster erosion, we instead measure nearly uniform tributary erosion rates above and within the mainstem knickzone. Simulations show that river incision into a more erodible layer of rock, with or without a river capture, could produce the observed topography and erosion rates in the South Fork Roanoke River. Our results show how multiple lines of evidence can illuminate the rates and mechanisms of river basin reorganization.

Геоинформационная система «Речные бассейны России»

An electronic map of basin geosystems of small rivers has been created for almost the entire mainland of Russia. The form of representation is a vector layer of polygonal objects; spatial detail corresponds to the regional level of generalization (scale 1:1 000 000). The research was performed in three stages: 1) The European Part of Russia (with the exception of the Crimea and the Kaliningrad region); 2) The Arctic watershed area of the Asian Part of Russia; 3) The Pacific watershed area (Far Eastern Federal District). In total, over 388 000 objects (basins) have been allocated with an average area of about 47.8 km2. The method used for constructing the basin map includes: selection of the base DEM and the hydro grid map; selection of geometric parameters of the raster grid to represent the initial data and the results of model calculations; correction of the DEM using the hydro grid map; construction of watershed basin boundaries in automatic mode; assessment of the accuracy of the allocation of river basin boundaries for different types of terrain. A specialized geoinformation system “Basins of small rivers of Russia” has been formed. GIS integrates geoinformation representing natural (geomorphometry of the relief, the hydro-climatic parameters, sediment yield and river flow, soils, landscapes) and anthropogenic (land use types, population, transport network, etc.) characteristics of river basins. As an example of solving geoecological and geographical problems, calculations of the intensity of soil erosion for the Lena River basin using a modified model of soil loss are presented. The average value of soil erosion losses in the Lena River basin, taking into account the types of land cover, is 0.22 t/ha/year. This generally indicates a very low intensity of erosion, most of the basin area belongs to the nonhazardous category of soil loss.

The Surface Water and Ocean Topography (SWOT) Mission River Database (SWORD): A Global River Network for Satellite Data Products

AbstractThe upcoming Surface Water and Ocean Topography (SWOT) satellite mission, planned to launch in 2022, is the first mission to focus on measuring hydrological processes in Earth's surface water. As such, SWOT will vastly expand observations of global rivers ≥100 m wide. SWOT will provide a variety of data products, including a global vector river product containing water surface elevation (WSE), width, slope, and estimated discharge. Practical application and consistency of the SWOT vector products requires a prior global river network database divided into reaches. Here, we introduce the SWOT River Database (SWORD). SWORD will serve as the framework for the SWOT river vector products consisting of river reaches (∼10 km long) and nodes (∼200 m spacing). We generate SWORD by combining several global river‐ and satellite‐related data sets into one congruent product. When defining river reaches, we incorporate natural and human‐created river obstructions, basin boundaries, tributary junctions, and SWOT orbit track information. SWORD contains a total of 213,485 reaches and 10.7 million nodes. Globally, 77.3% of river reach lengths are between 10 and 20 km with a median reach length of 10.5 km. 95% of river reaches ≥10 km will have sufficient SWOT observations to provide discharge estimates at least once per orbit cycle. SWORD also contains many useful hydrologic and morphological attributes and is designed to be expandable in the future. Even before the launch of SWOT, it can serve as a framework for global hydrologic analyses using models, in situ measurements, and additional satellite observations.

Research of clean drinking water provision the population of the Kemerovo region-Kuzbass

Many regions of Russian Federation have serious problems with water supply. Despite the significant water resource potential, including ground, surface and mineral waters, not all the population of the Kemerovo region is provided with clean drinking water. Besides the location of heavy industry enterprises, especially coal mines and pits, within the boundaries of river basins affects the condition and quality of water from different water sources. The purpose of this paper is to provide a research of clean drinking water providing the population of the Kemerovo region-Kuzbass, formulate the main problems and identify possible areas of activity in the field of increasing the availability of clean drinking water for the population of Kemerovo region-Kuzbass.

Fuzzy Postprocessing to Advance the Quality of Continental Seasonal Hydrological Forecasts for River Basin Management

AbstractStreamflow forecasting services driven by seasonal meteorological forecasts from dynamic prediction systems deliver valuable information for decision-making in the water sector. Moving beyond the traditional river basin boundaries, large-scale hydrological models enable a coordinated, efficient, and harmonized anticipation and management of water-related risks (droughts, floods). However, the use of forecasts from such models at the river basin scale remains a challenge, depending on how the model reproduces the hydrological features of each particular river basin. Consequently, postprocessing of forecasts is a crucial step to ensure usefulness at the river basin scale. In this paper we present a methodology to postprocess seasonal streamflow forecasts from large-scale hydrological models and advance their quality for local applications. It consists of fuzzy logic systems that bias-adjust seasonal forecasts from a large-scale hydrological model by comparing its modeled streamflows with local observations. The methodology is demonstrated using forecasts from the pan-European hydrological model E-HYPE at the Jucar River basin (Spain). Fuzzy postprocessed forecasts are compared to postprocessed forecasts derived from a quantile mapping approach as a benchmark. Fuzzy postprocessing was able to provide skillful streamflow forecasts for the Jucar River basin, keeping most of the skill of raw E-HYPE forecasts and also outperforming quantile-mapping-based forecasts. The proposed methodology offers an efficient one-to-one mapping between large-scale modeled streamflows and basin-scale observations preserving its temporal dependence structure and can adapt its input set to increase the skill of postprocessed forecasts.

The economic impacts of water supply restrictions due to climate and policy change: A transboundary river basin supply-side input-output analysis

Finding sustainable pathways to efficiently allocate limited available water resources among increasingly competing water uses has become crucial due to climate-change-induced water shortages and increasing water demand. This has led to an urgent need for the inclusion of economic principles, models, and methods in water resources management. Although several studies have developed macro-economic models to evaluate the economic impacts of alternative water allocation strategies, many if not most ignore the hydrological boundaries of transboundary river basins. Furthermore, of those using input-output (IO) models, only a handful have applied supply-side IO models. In this paper, we present one of the first attempts to develop an inter-regional, supply-side IO modelling framework for a multi-jurisdictional, transboundary river basin to assess the direct and indirect economic impacts of water supply restrictions due to climate and policy change. Applying this framework to the Saskatchewan River Basin in Canada encompassing three provinces, we investigate the economic impacts of two different water supply restriction scenarios on the entire river basin and its sub-basins individually. We find that in the face of climate-change-induced water shortage, economic losses can be reduced by almost 50% by adopting appropriate management practices, including prioritization of water allocation, using alternative water sources, and water re-use technologies.

Ecological Resilience Restoration in the Watershed of the Hancang River

Hancang River is a river on the eastern border of Jinan City. In recent years, with the development of cities, river flow has dropped sharply, river water has been polluted, and the ecological environment of the basin has declined. Improving the water ecological environment and enhancing the resilience of the water ecology of the river basin were set as the research goals, especially coupling of hydrological and ecological processes and the recycling of sewage resources. The “patch-corridor-matrix” theory of landscape ecology, the Least-cost distance model and the Arc Hydro Tools module of the ArcGIS platform were used to describe the river system and basin boundaries, optimize the current water network and the path network of the ecosystem. A novel ecological network and water network were proposed to form the final aquatic ecosystem, which combines the hydrological process with the ecosystem, and three decentralized wastewater treatment systems were designed to reduce the wastewater directly flowing into the river. The ecosystem resilience of the basin will be enhanced.

Water-resource substantiation of strategic planning in the regions of the Ob-Irtysh basin

The paper substantiates the need to conduct water assessment for the strategic planning documents of the regions, including the elaboration of strategies and the forecasts of long-term socio-economic development of the Russian Federation. In this regard, we present the theoretical and methodological approach and the algorithm of such assessments. The approach is based on the landscape-basin principle of territory organization. On the example of the Ob-Irtysh basin regions, the assessing has revealed water availability in the territories, anthropogenic load, water intensity, water consumption forecast, and prospects for water resources use. They indicate local water shortage in some landscape provinces of Omsk Oblast with a total population of more than 130 thousand people. Within the boundaries of river basins, we have estimated the anthropogenic load of low and medium intensity and calculated water intensity of territories (municipal districts), including for different types of economic activity and yearly dynamics. These results have been also a basis for forecasting the prospective use of water resources for drinking, industrial, irrigation and agricultural purposes. Using the forecasts, we have developed scenarios of the water supply of the regions, considering water content (minimum, maximum and average) of the period.

The River Basin Spatial Informative Nesting (E-BASIN) framework as an alternative approach for flood disaster management

The usage of technology is vital towards flood management. It helps on delivering the information on disasters occurred in the affected areas. Heavy rainfall and flood disaster occur frequently in Malaysia during the monsoon seasons. This causes significant impact towards human life, loss of properties and damage to the surrounding environment. The requirement on effective flood disaster management within river basin boundaries has become a necessity by managing the weather records, simulating present and future flood events; and providing best approach of reducing flood impact assessment before, during and after. This article aims to propose a new framework in flood disaster management as an alternative way to disseminate flood events, namely E-Basin framework. E-Basin is designed via “light and easy” approach to visualise, alert and report flood events among affected local residents, societies and related agencies situated in flood-prone areas. The implementation of E-Basin framework could provide further guideline among the involved agencies for improving effectiveness of flood disaster management geographically in the 4th Industrial Revolution era.

Towards a climate-driven simulation of coupled surface-subsurface hydrology at the continental scale: a Canadian example

The development of new, large-scale tools to evaluate water resources is critical to understanding the long-term sustainability of this resource under future land use, climate change, and population growth. In cold and humid regions it is imperative that such tools consider the hydrologic complexities associated with permafrost and groundwater-surface water (GW-SW) interactions, as these factors are recognized to have significant influence on the global water cycle. In this work we present a physics-based, three-dimensional, fully-integrated GW-SW model for Continental Canada constructed with the HydroGeoSphere simulation platform. The Canadian Continental Basin Model (CCBM) domain, which covers approximately 10.5 million km2, is discretized using an unstructured control-volume finite element mesh that conforms to key river basin boundaries, lakes, and river networks. In order to construct the model, surficial geology maps were assembled, which were combined with near-surface information and bedrock geology into a seven-layer subsurface domain. For the large-scale demonstration, the model was used to simulate historic groundwater levels, surface water flow rates (R2=0.85), and lake levels (R2=0.99) across the domain, with results showing that these targets are well reproduced. To demonstrate the regional-scale utility, simulation results were used to perform a regional groundwater flow analysis for western Canada and a water balance analysis for the Laurentian Great Lakes (Superior, Michigan, Huron, Erie and Ontario). The outcome of this work demonstrates that large-scale fully-integrated hydrologic modeling is possible and can be employed to quantify components of a large-scale water balance that are otherwise difficult or impossible to obtain.

Precision mapping of boundaries of flood plain river basins using high-resolution satellite imagery: A case study of the Varuna river basin in Uttar Pradesh, India

Accurate demarcation of river basin boundaries is an important input for any programme connected with watershed management. In the present study, the boundary of the Varuna river basin is automatically derived using coarse- and medium-resolution digital elevation models (DEMs) of SRTM-30 m, ASTER-30 m, Cartosat-30 m, ALOS Palsar-12.5 m and Cartosat-10 m as well as manually through on-screen digitisation from a very high-resolution 1 m $$\times $$ 1 m remote sensing data available as Google Earth image. The study demonstrated the efficacy of on-screen digitisation from high-resolution Google Earth image supported by detailed field observations in the precision mapping of the place of origin of the Varuna River, its stream network and basin boundary when compared to the maps generated through automatic methods using DEMs of various resolutions. The Varuna river system takes its headwaters from the areas surrounding Umran and Dain ‘tals’ (shallow, large depressions/basins) but not from the west of Mau Aima town as has been previously reported.

Genome-wide data delimits multiple climate-determined species ranges in a widespread Australian fish, the golden perch (Macquaria ambigua)

Species range limits often fluctuate in space and time in response to variation in environmental factors and to gradual niche evolution due to changes in adaptive traits. We used genome-wide data to investigate evolutionary divergence and species range limits in a generalist and highly dispersive fish species that shows an unusually wide distribution across arid and semi-arid regions of Australia. We generated ddRAD data (18,979 filtered SNPs and 1.725million bp of sequences) for samples from 27 localities spanning the native range of golden perch, Macquaria ambigua (Teleostei; Percichthyidae). Our analytical framework uses population genomics to assess connectivity and population structure using model-based and model-free approaches, phylogenetics to clarify evolutionary relationships, and a coalescent-based Bayesian species delimitation method to assess statistical support of inferred species boundaries. Addressing uncertainties regarding range limits and taxonomy is particularly relevant for this iconic Australian species because of the intensive stocking activities undertaken to support its recreational fishery and its predicted range shifts associated with ongoing climate change. Strong population genomic, phylogenetic, and coalescent species delimitation support was obtained for three separately evolving metapopulation lineages, each lineage should be considered a distinct cryptic species of golden perch. Their range limits match the climate-determined boundaries of main river basins, despite the ability of golden perch to cross drainage divides. We also identified cases suggestive of anthropogenic hybridization between lineages due to stocking of this recreationally important fish, as well as a potential hybrid zone with a temporally stable pattern of admixture. Our work informs on the consequences of aridification in the evolution of aquatic organisms, a topic poorly represented in the literature. It also shows that genome-scale data can substantially improve and rectify inferences about taxonomy, hybridization and conservation management previously proposed by detailed genetic studies.

Analyzing Future Water Scarcity in Computable General Equilibrium Models

Incorporating water into a computable general equilibrium (CGE) model operating at global scale can be extremely demanding due to the absence of standardized data, the sheer dimensions caused by intersecting river basins with countries, and difficulties to model demand for and supply of water. This has led many authors to introduce water in their CGE modeling framework in different ways and at different spatial and sectoral aggregation levels. Of course, simplifying market for water and sacrificing the geographical realism risk introducing errors caused by inappropriate aggregation. In this paper, we use an elaborate global CGE model to investigate the three most commonly practiced simplifications: (1) tackling global questions in a national level model; (2) collapsing irrigated and rainfed crop production into a single sector; and (3) removing river basin boundaries within a country. In each case, we compare their performance in predicting the impacts of future irrigation scarcity on international trade, crop output, land use change and welfare, relative to the full scale model. As might be expected, the single region model does a good job of matching outcomes for that region, although changes in bilateral trade can entail significant errors. When it comes to the elimination of sub-national river basins and irrigation location, we find that, if the research question has to do with changes in national-scale trade, production and welfare changes, it may be sufficient to ignore the sub-national hydrological boundaries in global economic analysis of water scarcity. However, when decision makers have an interest in the distribution of inputs and outputs within a region, preserving the river basin and sectoral detail in the model brings considerable added value to the analysis.

Cooperative and adaptive transboundary water governance in Canada’s Mackenzie River Basin: status and prospects

Morris, M., and R. C. De Loë. 2016. Cooperative and adaptive transboundary water governance in Canada’s Mackenzie River Basin: status and prospects. Ecology and Society 21(1):26.http://dx.doi.org/10.5751/ES-08301-210126

Determination of Watershed Boundaries in Turkey by GIS Based Hydrological River Basin Coding

A study was performed to develop hydrological river basin coding for Turkish river basins using the pfafstetter coding system. The coding system developed in this study is based on the combination of ECRINS and pfafstetter methods. River Basin District concepts were incorporated in this method so that it can be applicable to the management of Turkish River Basins. Developed hydrological river basin coding system is flexible, versatile and fits to all types of basins in Turkey. In order to show the efficiency of the coding system, it was applied to three river basins each of which has different hydrological and topographical features from the others. The basins used for the application of the coding system have complex features such as being transboundary basins, or being coastal basins whose discharge is not joining to the main drainage system, or being a closed basin discharging to an inland lake. Using the developed hydrological river basin coding defines river basin boundaries accurately, preventing conflicts in sectorial water allocation that are caused by uncertainty in the locations of water sources, producing a base for determining water potential and estimating extreme hydrological events of the basin, producing a basis for the prevention of water disputes among stakeholders within the basin, and helping implementation of Integrated Water Resources Management (IWRM) at basin level.

GLOBAL GEOINFORMATION SYSTEM “SUSPENDED SEDIMENT YIELD IN THE RIVER BASINS OF THE EARTH”

General-theoretical and methodical problems of creation and use of the global geoinformation system, which reflects the basic regularity of formation, spatial and temporal variability of suspended sediment yield of the Earth’s rivers, are considered. The role of river basins as geosystem formation in research of sediment yield is shown. Approaches to the automatic detection of river basin boundaries, methods of geoinformation system integration with thematic databases for purpose of geomorphological analysis of river suspended sediment yield are offered and tested.

Climate change and sectors of the surface water cycle In CMIP5 projections

Abstract. Results from 10 global climate change models are synthesized to investigate changes in extremes, defined as wettest and driest deciles in precipitation, soil moisture and runoff based on each model's historical 20th century simulated climatology. Under a moderate warming scenario, regional increases in drought frequency are found with little increase in floods. For more severe warming, both drought and flood become much more prevalent, with nearly the entire globe significantly affected. Soil moisture changes tend toward drying, while runoff trends toward flood. To determine how different sectors of society dependent on various components of the surface water cycle may be affected, changes in monthly means and interannual variability are compared to data sets of crop distribution and river basin boundaries. For precipitation, changes in interannual variability can be important even when there is little change in the long-term mean. Over 20% of the globe is projected to experience a combination of reduced precipitation and increased variability under severe warming. There are large differences in the vulnerability of different types of crops, depending on their spatial distributions. Increases in soil moisture variability are again found to be a threat even where soil moisture is not projected to decrease. The combination of increased variability and greater annual discharge over many basins portends increased risk of river flooding, although a number of basins are projected to suffer surface water shortages.