Statistical analysis of maximum runoff of the Southern Buh River using the method of ‘Indicators of Hydrologic Alteration’

Knowledge of maximum river runoff trends is of great practical importance, especially for design and operation of hydraulic structures. This article presents the results of the research of the Southern Buh River's maximum runoff. The water of the river is widely used for hydropower engineering, industrial and municipal water supply, agriculture, irrigation, shipping, tourism etc. The research of the maximum runoff was based on the Indicators of Hydrologic Alteration (IHA) method which is widely used in the whole world. This method enables calculation of quantitative statistical characteristics of rivers', lakes', reservoirs' runoff and determination of the degree of their hydrological regime changes. The IHA is used for water bodies having natural or regulated runoff. However, the IHA method was not widely used in Ukraine before. The purpose of this publication is using the Indicators of Hydrologic Alterations method in order to study the characteristics of maximum runoff and their changes along the Southern Buh River. The research was carried out based on the data of observations at 5 gauge stations located along the Southern Buh River. The research uses the mean daily discharges that has been recorded since the beginning of observations up to 2018 and 2019 inclusive. The river's runoff at each of gauge stations was divided into five components: "Extremely low runoff", "Low runoff", "High runoff pulses", "Small floods", "Large floods". This made it possible to separate three classes of high (maximum) runoff, for which the IHA statistics were calculated, from the total runoff. It was discovered that the long-term high runoff changes differed in each of its three components, although they had general trends. The most significant changes were found for large floods, with no significant changes found for high runoff pulses. General trends of high runoff showed that over time the values of maximum discharges tend to decrease, with the increasing duration of high runoff periods. The values of the main statistical indicators of high runoff gradually increase from the river's source to its mouth, which fully corresponds to the physical and geographical conditions of its formation. Nevertheless, some features of high runoff were still found. Thus small floods and high runoff pulses have the largest duration in the upper reach of the river. On average, the Southern Buh River experiences large floods once in every 10 years, small floods - once in every 2 years, high runoff pulses - 4-8 times a year in its upper reach and 9-14 times a year in its middle reach.

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ASSESSMENT OF HYDROLOGICAL CHANGES IN THE ŠUŠVĖ RIVER

Proceedings of the 7th International Scientific Conference Rural Development 2015 ◽

10.15544/rd.2015.035 ◽

2015 ◽

Author(s):

Gražina ŽIBIENĖ ◽

Alvydas ŽIBAS ◽

Goda BLAŽAITYTĖ

Keyword(s):

Hydrological Regime ◽

Maximum Flow ◽

Environmental Flow ◽

Physical Structure ◽

River Channels ◽

Hydrologic Alteration ◽

Water Conditions ◽

Flow Components ◽

The Impact ◽

Large Floods

The construction of dams in rivers negatively affects ecosystems because dams violate the continuity of rivers, transform the biological and physical structure of the river channels, and the most importantly – alter the hydrological regime. The impact on the hydrology of the river can occur through reducing or increasing flows, altering seasonality of flows, changing the frequency, duration and timing of flow events, etc. In order to determine the extent of the mentioned changes, The Indicators of Hydrologic Alteration (IHA) software was used in this paper. The results showed that after the construction of Angiriai dam, such changes occurred in IHA Parameters group as: the water conditions of April month decreased by 31 %; 1-day, 3-days, 7-days and 30-days maximum flow decreased; the date of minimum flow occurred 21 days later; duration of high and low pulses and the frequency of low pulses decreased, but the frequency of high pulses increased, etc. The analysis of the Environmental Flow Components showed, that the essential differences were recorded in groups of the small and large floods, when, after the establishment of the Šušvė Reservoir, the large floods no longer took place and the probability of frequency of the small floods didn’t exceed 1 time per year.

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Assessment of dam construction impact on hydrological regime changes in lowland river – A case of study: the Stare Miasto reservoir located on the Powa River

Journal of Water and Land Development ◽

10.1515/jwld-2016-0028 ◽

2016 ◽

Vol 30 (1) ◽

pp. 119-125 ◽

Cited By ~ 5

Author(s):

Mariusz Sojka ◽

Joanna Jaskuła ◽

Joanna Wicher-Dysarz ◽

Tomasz Dysarz

Keyword(s):

Peak Flow ◽

Hydrological Regime ◽

Dam Construction ◽

Lowland River ◽

Hydrologic Alteration ◽

Regime Changes ◽

Gauge Station ◽

Range Of Variability Approach ◽

Positive Effect ◽

Daily Flows

Abstract The purpose of the presented research is analysis and assessment of the Stare Miasto reservoir impact on the hydrological regime changes of the Powa River. The reservoir was built in 2006 and is located in the central part of Poland. The total area of inundation in normal conditions is 90.68 ha and its capacity is 2.159 mln m3. Hydrological regime alteration of the Powa River is analysed on the basis of daily flows from the Posoka gauge station observed during period 1974–2014. Assessment of hydrological regime changes is carried out on the basis of Range of Variability Approach (RVA) method. All calculations are made by means of Indicators of Hydrologic Alteration (IHA) software version 7.1.0.10. The analysis shows that the Stare Miasto reservoir has a moderate impact on hydrological regime of the Powa River. Construction of the reservoir has positive effect on stability of minimal flows, which are important for protection of river ecosystems. The results obtained indicate that the Stare Miasto reservoir reduces a spring peak flow and enables to moderate control of floods.

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Long-term changes of river discharge regime in Latvia

Hydrology Research ◽

10.2166/nh.2008.033 ◽

2008 ◽

Vol 39 (2) ◽

pp. 133-141 ◽

Cited By ~ 5

Author(s):

Maris Klavins ◽

Valery Rodinov

Keyword(s):

Climate Variability ◽

River Discharge ◽

Water Resource Management ◽

Regional Climate ◽

Hydrological Regime ◽

High Water ◽

Regime Changes ◽

Long Term Changes ◽

Discharge Regime

The study of changes in river discharge is important for regional climate variability characterization and for development of an efficient water resource management system. The hydrological regime of rivers and their long-term changes in Latvia were investigated. Four major types of river hydrological regimes, which depend on climatic and physicogeographic factors, were characterized. These factors are linked to the changes observed in river discharge. Periodic oscillations of discharge, and low- and high-water flow years are common for the major rivers in Latvia. A main frequency of river discharge regime changes of about 20 and 13 years was estimated for the studied rivers. A significant impact of climate variability on the river discharge regime has been found.

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BOC signals processing by two traditional correlator channels

Radioengineering ◽

10.18127/j00338486-202109-01 ◽

2021 ◽

pp. 5-17

Author(s):

O.K. Mikhaylova ◽

I.V. Korogodin

Keyword(s):

Direct Method ◽

Tracking System ◽

Practical Importance ◽

Reference Signal ◽

Processing Algorithm ◽

Statistical Characteristics ◽

Navigation Systems ◽

Signal Delay ◽

Signal Processing Algorithm ◽

To Receive

Problem statement. With the development of satellite navigation systems, new navigation BOC signals are being introduced. Since the structure of BOC signals differs from traditional BPSK signals, this complicates their processing, which may require hardware changes and often leads to the need to develop new ones. Objective. Synthesis and analysis of the BOC signal processing algorithm using two BPSK correlators, comparable in accuracy to the direct method. Results. The synthesis and analysis of the BOC signal delay tracking system using two correlators, originally designed to receive only BPSK-conducting signals, are carried out. The statistical characteristics of the delay discriminator are obtained. It is shown how the accuracy and sensitivity of the obtained delay tracking algorithm are correlated with respect to the reference algorithm, which assumes the use of a signal with a digital subcarrier in the reference signal of the correlator. The pull-in characteristic are obtained. Practical relevance. The processing algorithm BOC signals that doesn't require modification of the traditional correlators of the navigation receiver is presented. This algorithm is of great practical importance, since it allows for high-precision reception of modern BOC and AltBOC signals, despite the limitations characteristic of modern navigation equipment. For example, this algorithm allows to receive Galileo E5 signals using the popular NTLab NT1065 chip. A new signal pull-in algorithm is proposed. This algorithm allows to avoid abnormal tracking errors caused by the operation of the tracking system in the side zones of the s-curve. The pull-in characteristics for various receive conditions are given.

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Development of calculated and normative framework in the field of maximum runoff of rain and spring flood: problems and possible solutions

Ukrainian hydrometeorological journal ◽

10.31481/uhmj.16.2015.21 ◽

2017 ◽

pp. 164-170

Author(s):

E.D. Gopchenko ◽

M.E. Romanchuk ◽

V.A. Ovcharuk

Keyword(s):

Geometric Model ◽

Hydrological Regime ◽

Regulatory Document ◽

Spring Flood ◽

Probability Of Exceedance ◽

Normative Framework ◽

Direct Observations ◽

Design Characteristics ◽

Definition Of ◽

Maximum Runoff

The article deals with the problematic issues related to the definition of the design characteristics of the maximum runoff of rain and spring floods the rare probability of exceedance in the case absence of direct observations for hydrological regime of rivers. A brief review of foreign and domestic methods to determine the maximum runoff of the rivers is discussed. A new calculated and normative framework based on the theory of channel isochronous with using geometric model of slope and streamflow hydrographs are proposed. The formulas proposed by the authors is recommended for practical use, as a supplement to a new regulatory document, which is being developed in Ukraine.

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An operational method for the ecohydrological classification of temporary rivers and streams

10.5194/egusphere-egu21-4360 ◽

2021 ◽

Author(s):

Francesc Gallart ◽

Núria Cid ◽

Pilar Llorens ◽

Jérôme Latron ◽

Núria Bonada ◽

...

Keyword(s):

Hydrological Regime ◽

Sources Of Information ◽

Hydrologic Alteration ◽

Aquatic Life ◽

Temporary Streams ◽

Drainage Networks ◽

Water Courses ◽

Riverine Systems

Water courses that recurrently cease to flow represent a large part of drainage networks, and are expected to expand with global warming and increased exploitation of water resources. Common classifications of the regime of these temporary streams are based on the statistics of zero flow events. This is partly practical because these statistics can be obtained from flow records or model simulations and the results can be used for some environmental regulations or management purposes.Nevertheless, it is well known that the main hydrological control on riverine aquatic life is the presence-absence of water rather than its flow regime. Disconnected pools that frequently remain in temporary streams after flow cessation provide valuable refuges for aquatic life, which can last up to all year round. An operational characterisation of the hydrological regime of temporary streams useful for ecological purposes must therefore take into account at least the three main aquatic phases that they undergo: flow, disconnected pools and dry stream bed. However, gauging stations and the derived hydrological models may only marginally inform about the possible occurrence of disconnected pools after the cessation of flow.In order to facilitate the implementation of the European Water Framework Directive to the temporary streams, an operational approach has been developed to describe and classify the regime of temporary streams and to assess their degree of hydrologic alteration, relevant to aquatic life. This approach is encapsulated in the freely available TREHS software. The first step of this approach is the gathering of information on the frequency of the three aquatic phases using diverse sources of information, such as flow records and simulations,&#160;in situ observations, interpretation of aerial or terrestrial series of photographs, and interviews with local inhabitants or technicians familiar with the riverine systems. Up to six metrics describing these frequencies and their temporal patterns of occurrence are used to determine the natural and observed stream regime, and to assess the degree of hydrological alteration.The combination of the complementary frequencies of the three main aquatic phases allows the description of the regime of every stream as a point in a ternary plot, where the three vertices of the triangle represent the perennial streams, the perennial pools and the terrestrial systems, respectively. This ternary plot assists the classification of the regime of any stream that takes into account the statistics of the main proxies of the occurrence of aquatic habitats. The TREHS software also provides a classification of the regimes in the ternary plot that groups the regimes of assumed ecological significance and uses terms that are conflict-free from the current classifications. Furthermore, TREHS users can easily define new regime classes in this plot according to the ecohydrological characteristics of their streams.

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Forest watershed runoff changes determined using the unit hydrograph method

Journal of Forest Science ◽

10.17221/94/2008-jfs ◽

2009 ◽

Vol 55 (No. 2) ◽

pp. 89-95

Author(s):

V. Černohous ◽

P. Kovář

Keyword(s):

Least Squares ◽

Least Squares Method ◽

Forest Stand ◽

Unit Hydrograph ◽

Stand Growth ◽

Total Runoff ◽

Runoff Changes ◽

Recession Limb ◽

Unit Hydrographs ◽

Maximum Runoff

Unit hydrograph is a basic method to show changes in runoff in the watershed. The investigation of runoff changes was carried out in the U Dvou louček watershed situated at the summit part of the Orlické hory Mts., East Bohemia. The waveform ordinates of recession limbs of unit hydrographs obtained using a common approach had to be approximated by the least-squares method. Final hydrographs reflected both drainage treatment and forest stand growth influencing the runoff from the watershed. Both factors increase culmination in synergy and reduce runoff on the recession limb of the hydrograph. We confirmed increased maximum runoff taking up 25–30% of the total runoff time when waterlogged sites were drained. The culmination increased by 0.2–0.8 mm/hour indicates the runoff increased by 2–8 m3/ha/hr.

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Hydrological regime changes in a Canadian Prairie basin

Hydrological Processes ◽

10.1002/hyp.10567 ◽

2015 ◽

Vol 29 (18) ◽

pp. 3893-3904 ◽

Cited By ~ 76

Author(s):

Stacey Dumanski ◽

John W. Pomeroy ◽

Cherie J. Westbrook

Keyword(s):

Hydrological Regime ◽

Canadian Prairie ◽

Regime Changes

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Spring flood frequency analysis in the Southern Buh River Basin, Ukraine

Journal of Geology Geography and Geoecology ◽

10.15421/112122 ◽

2021 ◽

Vol 30 (2) ◽

pp. 250-260

Author(s):

Liudmyla O. Gorbachova ◽

Viktoria S. Prykhodkina ◽

Borys F. Khrystiuk

Keyword(s):

Time Series ◽

River Basin ◽

Frequency Analysis ◽

Practical Importance ◽

Statistical Characteristics ◽

Flood Frequency Analysis ◽

Spring Flood ◽

Cyclical Fluctuations ◽

Pearson Type ◽

Maximal Runoff

The river floods are among the most dangerous natural disasters in the world. Each year, the spring floods cause the significant material damage in the different countries, including Ukraine. Knowledge of trends in such floods, as well as their probabilistic forecast, is of great scientific and practical importance. In last decades, the decreasing phase of cyclical fluctuations of the maximum runoff of spring floods has been observed on the plain rivers of Ukraine, including the Southern Bug River. In addition, there is an increase in air temperature. So, the actual task is the determine the modern probable maximum discharges estimates of spring floods in the Southern Buh River Basin as well as their comparison with the estimates that were computed earlier. It gives an opportunity to reveal possible changes of the statistical characteristics and values of the probable maximum discharges, to analyze and to discuss the reasons for these changes. For the investigation, we used the time series of the maximum discharges of spring floods for 21 gauging stations in the Southern Buh River Basin since the beginning of the observations and till 2015. The method of the regression on the variable that is based on the data of analogues rivers was used to bringing up the duration of the time series and restoration of the gaps. In the study, the hydro-genetic methods for estimation of the homogeneity and stationarity of hydrological series, namely the mass curve, the residual mass curve and the combined graphs. The distributions of Kritskyi & Menkel and Pearson type III for the frequency analysis were used. It has been shown in this study that the maximum discharges of spring floods of time series are quasi-homogeneous and quasi-stationary. It is explained the presence in the observation series of only increasing and decreasing phases of cyclical fluctuations, their considerable duration, as well as the significant variability of the maximal flow. The series of maximal runoff of spring floods are very asymmetric, which significantly complicates the selection of analytical distribution curves. The updated current parameters of the maximal spring flood runoff have not changed significantly. It can be assumed that such characteristics have already become stable over time, as the series of maximal runoff of spring floods already have phases of increasing and decreasing of long-term cyclic fluctuations.

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