Wyniki wyszukiwania - Biblioteka Nauki

1

The transport and distribution of the river load from the Kacza River into the Gulf of Gdańsk (Southern Baltic Sea, Poland)

100%

Szymczak E. , Rhode D. , Piekarek-Jankowska H.

Oceanological and Hydrobiological Studies

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2011

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tom Vol. 40, No.4

1-10

EN

The results of measurements of suspended sediment and bed load carried by the Kacza River into the Gulf of Gdańsk are discussed. The investigations were conducted in the years 2009–2010 at the Orłowo transect and at the mouth of the Kacza River in the Gulf of Gdańsk. The research has shown that the Kacza River discharged about 673 tons of sediment annually to the Gulf of Gdańsk, with 77% being transported as bed load. The granulometric composition of the river load is dominated by coarse-grained sand fractions.

2

Transport of the river load from the Błądzikowski stream to the puck lagoon (southern Baltic Sea, Poland) [commun.]

100%

Damaszke M. , Szymczak E.

Oceanological and Hydrobiological Studies

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2013

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tom Vol. 42, No. 2

216-224

EN

The main aim of this study was to determine the size of the load carried by the Błądzikowski Stream and discharged into the Puck Lagoon, and the role of the river load in the formation of the sea bed deposits at the stream mouth. The Błądzikowski Stream, with the length of only 10 km, discharges about 610 tons of sediment into the Puck Lagoon per year, including 89.8% (548 tons) of the bed load and 10.2% (62 tons) of the suspended load. The amount is 4.9% of the river load discharged into the Puck Lagoon. Mineral particles are more common in the composition of the river load and account for 94.6% of the suspended load and 98.7% of the bed load. It is mainly the bed load deposited in the estuarine area that creates a contemporary underwater accumulation form in the Puck Lagoon, which is corroborated by the granulometric composition of the channel and surface sediments; the suspended load is carried further into the Lagoon.

3

The transport of material by the rivers of the northern slope of the Pomeranian Lake Land to the Baltic Sea

88%

Szymczak E.

Oceanological Studies

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2002

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tom Vol. 31, No. 3-4

85-97

EN

The article presents the results of research on the transport of sediment carried by the rivers of the northern slope of the Pomeranian Lake Land to the Baltic Sea in the years 1961-1980. The research includes rivers flowing into the open sea: Rega, Parseta, Wieprza, Slupia, Lupawa and Leba. The total surface of the basins of the rivers in question amounts to 13825.1 km2. The analysis was conducted on the basis of the data concerning the turbidity and flow of the rivers included in hydrological year-books. The size of the transport of the sediment for respective rivers has been counted and the transport of the wash load was analysed with respect to changing conditions of the streamflow and to physical-geographical features of the basin. The transport of the sediment carried to the sea was estimated (46000 tons) and the participation of the rivers of the northern slope of the Pomeranian Lake Land in the total transport of the river wash load from the catchment area of the Baltic Sea has been estimated (0.63%).

4

Kelvin-Helmholtz instabilities in the Colorado River Delta, Gulf of California

88%

Carbajal N. , Vargas J. T. , Rodríguez J. H. G. , Ley Y. M. , León D. A. S. d.

Oceanologia

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2021

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tom No. 63 (3)

321--328

EN

In the Colorado River Delta, the interaction of tidal currents and sea-bottom sediment formed, in geological times, large-scale seabed patterns known as sandbanks. These patterns are oriented along the delta, almost parallel to the dominant tidal flow, with the bathymetry having an undulating character across the delta. Calculations and analysis showed that the interaction of tidal currents with the bathymetry causes velocity shears, faster flowing over the ridges than in the troughs. Kelvin-Helmholtz instabilities emerge from the velocity shear, and a large amount of suspended sediment makes the instabilities visible in satellite images. The physical and dynamic conditions allowed us to find an explanation for the existence of these Kelvin-Helmholtz instabilities. Since sandbanks have been observed in different seas such as the North Sea, The Gulf of Korea, the Gulf of Khambhat in India, the Jiangsu coast in China, the Persian Gulf, and Moreton Bay in Australia, the results suggest the existence of instabilities in these areas. Satellite images, intense tidal currents, undulating topography, and suspended sediment made it possible to explain the generation and identification of Kelvin-Helmholtz instabilities.

5

Daily Suspended Sediment Prediction Using Seasonal Time Series and Artificial Intelligence Techniques

88%

Üneş F. , Taşar B. , Demirci M. , Zelenakova M. , Kaya Y. Z. , Varçin H.

Rocznik Ochrona Środowiska

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2021

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tom Tom 23

117--137

EN

Estimating the amount of suspended sediment in rivers correctly is important due to the adverse impacts encountered during the design and maintenance of hydraulic structures such as dams, regulators, water channels and bridges. The sediment concentration and discharge currents have usually complex relationship, especially on long term scales, which can lead to high uncertainties in load estimates for certain components. In this paper, with several data-driven methods, including two types of perceptron support vector machines with radial basis function kernel (SVM-RBF), and poly kernel learning algorithms (SVM-PK), Library SVM (LibSVM), adaptive neuro-fuzzy (NF) and statistical approaches such as sediment rating curves (SRC), multi linear regression (MLR) are used for forecasting daily suspended sediment concentration from daily temperature of water and streamflow in the river. Daily data are measured at Augusta station by the US Geological Survey. 15 different input combinations (1 to 15) were used for SVM-PK, SVM-RBF, LibSVM, NF and MLR model studies. All approaches are compared to each other according to three statistical criteria; mean absolute errors (MAE), root mean square errors (RMSE) and correlation coefficient (R). Of the applied linear and nonlinear methods, LibSVM and NF have good results, but LibSVM generates a slightly better fit under whole daily sediment values.

6

Sedimentation of suspensions in the Vistula River mouth

88%

Szymczak E. , Galińska D.

Oceanological and Hydrobiological Studies

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2013

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tom Vol. 42, No. 2

195-201

EN

The aim of this study was to analyze the variability of the suspension concentration in the area where the Vistula River discharges into the Gulf of Gdańsk. While analyzing the relationship between suspension concentration and the distance from the river mouth and the spatial location in the water column, a number of other important factors were considered, i.e. salinity, temperature, the composition of suspension and in situ hydrodynamic conditions. The samples of surficial sediment were analyzed with regard to the content of organic matter and <0.063 mm size fraction.

7

Appraisal of methods of determination of sediment quantity supplied to a small water reservoir

75%

Michalec B.

Archives of Environmental Protection

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2008

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tom Vol. 34, no. 2

49-62

EN

The paper present the results of calculations of sediment quantity supplied to a small water reservoir at the locality of Zesławice. A detailed elaboration of physiographic parameters of the catchment of the Dlubnia River resulted in determination of the sediment yields by use of the Reniger-Debski's, of Branski's as well as DR-USLE and MUSLE methods. It was found that in the years 1966 to 1983 the mean annual inflow into the reservoir at Zestawice was 32 750 Mg according to the Reniger-Debski's method, 43 620 Mg according to the Branski's method, 17 020 Mg according to the DR-USLE method and 28 470 Mg according to the MUSLE method and according to measurements - 16 000 Mg. Calculations of suspended load transport using of the van Rijn's method was based on two measurements performed at flow 0.98 m's' and 1.51 m^3s_-1. The results of calculations obtained by use of the applied methods were compared with the results of silting quantity measurements in the reservoir at Zesławice

PL

W pracy przedstawiono wyniki obliczeń ilości rumowiska dostarczanego do małego zbiornika wodnego w Zesławicach. W wyniku szczegółowego opracowania parametrów fizjograficznych zlewni rzeki Dlubni określono wielkość denudacji odpływowej metodami Reniger-Dębskiego i Brańskiego oraz DR-USLE i MUSLR. Stwierdzono, że w okresie od 1966 do 1983 roku średni roczny dopływ rumowiska do zbiornika w Zesławicach wynosił odpowiednio: 32 750 Mg według metody Reniger-Dębskiego, 43 620 Mg według metody Brańskiego, 17 020 Mg według metody DR-USLE i 28 470 Mg według metody MUSLE, a według pomiarów - 16 000 Mg. Obliczenie ilości rumowiska unoszonego metodą van Rijna wykonano na podstawie dwóch pomiarów wykonanych przy przepływach wynoszących 0,98 m^3s^-1 i 1,51 m^3s^-1. Uzyskane wyniki obliczeń według zastosowanych metod porównano z wynikami pomiarów wielkości zamulenia zbiornika w Zesławicach.

8

Kelvin-Helmholtz instabilities in the Colorado River Delta, Gulf of California

75%

Carbajal N. , Vargas J. T. , Rodriguez J. H. G. , Montano Ley Y. , Salas de Leon D. A.

Oceanologia

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2021

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tom 63

|

nr 3

9

Spatial variations of suspended sediment grain size in small mountain catchment during summer floods

75%

Kijowska-Strugała M.

Studia Geomorphologica Carpatho-Balcanica

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2016

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tom Vol. 50

53--63

EN

The grain size of material transported during flood along the longitudinal profile of the small Carpathian stream (the Bystrzanka stream) and its main tributaries was examined. The silt fraction is the dominant material transported during floods. The average content of this fraction varies from 67 to 88%. The highest standard deviation was recorded in relation to the sand fraction, what have been linked with the human impact (especially in the channel). During the rising limb phase the sand fraction showed a higher percentage content than during decreasing limb (at the same water level) and contrary in the case of the finest fraction. There were observed a statistically significant (<0.05) inverse relationship between the sand and silt fraction and the sand and clay fraction. The study showed no statistically significant impact of factors (precipitation, discharge) controlling summer floods on the size of suspended sediment.

10

Suspended sediment concentration and yield in snowmelt flood events in a small lowland river

75%

Hejduk A. , Banasik K.

Annals of Warsaw University of Life Sciences - SGGW. Land Reclamation

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2010

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tom 42

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nr 1

61-68

EN

Results of investigation on suspended sediment delivery from small lowland, agriculturally used catchment of Zagożdżonka River, located in central Poland, during snowmelt periods of 2001– –2007 are presented. The study catchment‘s area, upstream of the well equipped gauging station at Czarna, is 23.4 km2. Suspended sediment concentration and sediment yield has been calculated and analysed for 15 snowmelt flood events. The relationship between suspended sediment concentration and the discharge has been analyzed. It has been found that the relation, in majority of the cases, has the form of clockwise hysteresis, however the existance of other types of hysteresis i.e. anticlockwise and “8” shape, have been also confi rmed. Signifi cant relation between suspended sediment yield and runoff volume of snowmelt flood events has been also found.

PL

W pracy przedstawiono wyniki badań transportu rumowiska unoszonego, przeprowadzonych w małej zlewni nizinnej (A = 23,4 km2) położonej na Równinie Radomskiej. Przeanalizowano 15 wezbrań z lat 2001–2007, dla których zarejestrowano kompletne dane obejmujące zasilanie zlewni, przepływ i koncentracje. Analiza zależności koncentracji z przepływem wskazuje na występowanie w większości z analizowanych zdarzeń histerezy prawostronnej (tj. zgodnej z ruchem wskazówek zegara). Koncentracja rumowiska unoszonego wzrastała wraz z przepływem, a jej kulminacja w większości z badanych przypadkach wystąpiła przed kulminacją przepływu. Ustalono zależność, statystycznie istotną, wydatku rumowiska od objętości wezbrania.

11

Water erosion and supply of material for fluvial transport under episodic surface flow conditions in the semi-arid zone on Boa Vista (Cabo Verde)

75%

Gierszewski P. , Rodzik J.

Landform Analysis

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2003

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tom Vol. 4

49--58

EN

This paper presents the effects of the natural conditions of the semi-arid zone on the tem-poral and spatial variability of production and supply of material for fluvial transport under conditions of episodic surface flow. Based on measurements of water runoff, concentration of suspension and dissolved material in the course of a one-hour rainfall, it has been determined that the catchments under study have a considerable resistance to the effects of water erosion. Some protection is supplied by the ablation pavement, which reduces rainsplash and slopewash and prevents flow concentration. Consid-erably more erosion has been noted on unpaved roads concentrating water flow even on plateaux and gently inclined slopes. Obviously the potential for leaching rock material in short-duration flow is limited. Large proportions of the dissolved material carried away from the catchments are salts of marine and aeolian provenance. The high intensity of erosional processes in the early phase of runoff is evidence of the role of physical weathering between rainfalls, which supplies the material for fluvial transport.

12

Influence of the manner of water discharge from dam reservoirs on downstream water quality

75%

Cieśla M. , Gruca-Rokosz R.

Journal of Water and Land Development

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2023

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tom no. 56

91--101

EN

The study was carried out in the area of three dam reservoirs: Blizne and Maziarnia (Voivodeship of Podkarpackie) and Nielisz (Voivodeship of Lublin). The main parameter differentiating the reservoirs was the water retention time and the manner of water discharge from the reservoirs. Three test sites were designated in the area of each reservoir: in the river zone of the reservoir, in the central part of the reservoir, and near the reservoir dam. At these sites, the concentrations of suspended sediment in the water and the content of organic matter in it, the concentrations of total phosphorus and total nitrogen, as well as chlorophyll a were monitored. In addition, two control sites were established: on the river upstream of the reservoir and on the river downstream of the dam, respectively. At these points, the concentrations of suspended sediments in the water and their organic matter content were recorded. The obtained results of the study and multivariate analysis of the data showed that morphometric parameters (including water retention time) of reservoirs and the method of water discharge influence water quality in downstream rivers. It was found that by using lower discharge and ensuring a sufficiently long retention time of water in the reservoir, it is possible to effectively limit the negative aspects of hydrotechnical structures’ impact on the natural environment. In practice, the observed relationships may constitute an important and missing link in the aspect of minimising undesirable side effects of this type of hydrotechnical objects.

13

Laboratory study of suspended sediment dynamics over a mildly sloping sandy seabed

75%

Stachurska B. , Staroszczyk R.

Oceanologia

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2019

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tom 61

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nr 3

14

Results of hydrological studies and channel analysis of the Ganges (Padma) River at the construction site of the “Rooppur” NPP

75%

Zavadsky A. S. , Botavin D. V. , Golovlev P. P. , Mikhailova N. M. , Morozova E. A. , Promakhova E. V. , Turykin L. A.

Geography and Tourism

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2018

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tom Vol. 6, No. 1

41--53

EN

This work presents the results of research on channel processes in the Padma River (Republic of Bangladesh) at the construction site of the “Ruppur” Nuclear Power Plant (NPP). The fluvial characteristics of the Padma River were presented, including: the water outflow regime, characteristics of anthropogenic impact on the river outflow and assessment of the present state of the channel and floodplain. The research was conducted based on field expeditions, during which data on morphology, dynamics, hydrological and hydraulic conditions for the formation of the floodplain-channel complex were collected. Moreover, the water discharges and suspended sediments, as well as the longitudinal profiles of the water level and the channel morphology were measured. The presented research has shown that comprehensive and planned regulation of selected sections of rivers could lead to the channel stabilization and support the rational use of water resources for different purposes, e.g. power plants, municipal purposes, etc. Moreover, detailed research on channel deformation in selected areas indicated the major role of natural factors (geological structure, the type of sediments delivered to the river, vegetation cover, etc.) in the past and present fluvial processes.

15

Estimation of Sediment Concentration Using Sediment Rating Curve Approach in Isser Watershed (North-West of Algeria)

63%

Baloul D. , Ghenim A. N. , Megnounif A.

Ecological Engineering & Environmental Technology

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2023

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tom Vol. 24, iss. 6

282--291

EN

This paper was elaborated in order to estimate suspended sediment in Isser watershed located in North-West of Algeria. Power functions models by least squares regression were developed to establish rating curves. In total, 2026 pairs of instantaneous water discharge (Q) and instantaneous suspended sediment concentration (C) from the period 1988–1989 to 2003–2004 were used. In order to reveal the temporal impact, four subdivision data are elaborated: all, annual, seasonal and monthly scales. Better estimation of the total suspended sediment yield was obtained by application of the power linear model in monthly division data (-0.16%). When considering efficiency, both models with seasonal scale offered coefficients in order of 0.95%. The approach of correction for models did not improve accuracy of the estimation. The results have indicated for the 16 years of the available data, that the Isser watershed has drained a total of 194.37 million m3 of water and 1.4 million tons of suspended sediments, with a specific degradation of 77 tons/km2/year.

16

Appraisal of suspended sediment concentration on reference level according to van Rijn’s method

63%

Michalec B.

Annals of Warsaw University of Life Sciences - SGGW. Land Reclamation

|

2008

|

tom 40

17

Transport i sedymentacja rumowiska unoszonego na zdjęciach lotniczych

63%

Dobrowolski A. , Głowacka B. , Kondzielski A.

Przegląd Naukowy Inżynieria i Kształtowanie Środowiska

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2008

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tom Vol. 17, No. 2

87--97

EN

Using optical features of water and suspended sediment, series of imageries of Polish rivers (mainly of Vistula River) and Loire River in France were registered from aircraft, beginning from 1990, at first with video-computer technique, later using the own aircraft system for fluent digital registration of a terrain. In the selected examples were presented images of suspended sediment with spatial differentiation of its concentration in river, in the morphologically different stretches. There were suggested possibilities of use of the suspended sediment as a tracer in researches of hydro-morphological processes, for ex. sedimentation and evaluation of the ecological state of rivers. In the range of examples use of airborne photographs was presented to the identification of sediment deposition zones in natural conditions and changed by human activity.

18

Evaluation of the effects of land-use change and increasing deforestation in the Sapanca Basin on total suspended solids (TSS) movement with predictive models

63%

Temiz T. , Sonmez O. , Dogan E. , Oner A. , Opan M.

Acta Geophysica

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2022

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tom Vol. 70, no 3

1331--1347

EN

Sapanca Lake is a tectonically sourced freshwater resource and one of the rare natural water resources used as a source of drinking water. This study examined the change of land use and lake area in the natural water source basin subjected to human pressure for years. Landsat 5 TM (1987) and Landsat 8 TM (2010) satellite images were used. Satellite images were analyzed using ArcGIS 10.1 software. As a result of the analysis, it was observed that the natural vegetation was significantly destroyed between 1987 and 2010. Besides, the bathymetry maps of Lake Sapanca belonging to the years 1990 and 2010 were also examined, and accordingly, it was determined that there was a 2% reduction in the lake surface area. The decrease in the volume of the lake was thought to be due to sedimentation movement caused by land-use change, and the total amount of suspended solids, grain size, discharge, and temperature measurements were made between 2012 and 2014 in 12 streams which are sources of Sapanca Lake. Sediment prediction models have been developed under two different scenarios using measurement data from side streams. Artificial neural networks (ANN), Sediment rating curve, and multiple linear regression models were examined within the scenario models, and comparisons were made between the models. It was determined that ANN achieved the closest results with the measurement data.

19

Wpływ rozdziału wód w węźle wodnym na intensywność zamulania dwóch zbiorników wodnych w układzie równoległym

63%

Michalec B.

Przegląd Naukowy Inżynieria i Kształtowanie Środowiska

|

2012

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tom Vol. 21, No. 3

141--150

PL

W pracy przedstawiono wpływ rozdziału przepływu wody w węźle wodnym zasilającym dwa zbiorniki w Zesławicach na intensywność ich zamulania. Przedstawiono metodykę określenia wpływu rozdziału wody w węźle wodnym i współczynnika proporcji pojemności dwóch zbiorników wodnych na ich żywotność. Wykazano, że rozdział wody w węźle wodnym ma wpływ na wartość zdolności zbiornika do zatrzymywania rumowiska oraz na wartość obliczonej objętości odkładów rumowiska po pierwszym roku eksploatacji (R1), a tym samym na czas eksploatacji zbiorników.

EN

The effect of the water flow distribution in the water node on the silting intensity of two water reservoirs was introduced in the work. Two water reservoirs in the parallel system are feeding of water inflowing to them from water node. Methodology of qualification of effect of the water distribution in the water node and coefficient of capacity proportion on two water reservoirs useful live was introduced. It was stated that the water distribution in the water node has the effect on the value of the silting trap efficiency of two water reservoirs in the parallel system, on the value of the calculated volume of the sediment deposited in reservoirs after first year of operation (R1), and the same on the time of the operation of reservoirs.

20

Acoustic based assessment of cross-sectional concentration inhomogeneity at a suspended sediment monitoring station in a large river

63%

Pomázi F. , Baranya S.

Acta Geophysica

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2022

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tom Vol. 70, no 5

2361--2377

EN

Establishing and operating a harmonized sediment monitoring system along large rivers such as the Danube River is a challenging international task. As an element of such a system, a new monitoring site with state-of-the-art instrumentation is currently under development in the Upper-Hungarian section of the Danube River. The monitoring station will consist of a nearbank optical backscatter sensor and a horizontal acoustic Doppler current profiler (H-ADCP). As previous studies showed, the suspended sediment concentration (SSC) that is continuously measured with near-bank sensors can significantly enhance the temporal resolution of sediment transport monitoring. However, sediment plumes from tributary inflows upstream of the monitoring station can alter the detected near-bank concentrations, eventually biasing the sediment load estimation. Such an influence is likely in the cross-section of the planned monitoring station, therefore, a thorough preliminary analysis of the cross-sectional variation of the SSC was performed, based on expeditionary sediment measurement campaigns. Between 2018 and 2021 24 campaigns were carried out at different hydrological regimes, where physical sediment samplings together with fixed and moving boat ADCP measurements were performed. The cross-sectional variability of SSC and its influence on the sediment load estimations were assessed based on the moving boat ADCP measurements, after calibrating the backscatter signal with more than 500 physical samples. Based on the results, we identified different cross-sectional patterns of the SSC which is apparently governed by: (i) the actual hydrological situation considering both the main river and the tributary, and (ii) the local river morphology. Based on our findings, we suggested a correction method that accounts for the above effects, using which the near-bank SSC can be reliably converted into total suspended sediment load.