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Flow characteristics of intermittent rivers in Slovakia

100%

Rutkowska A., Kohnova S., Banasik K., Szolgay J.

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

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2018

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tom 50

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nr 3

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Przepływy dyspozycyjne rzek Pomorza

86%

Duda L., Zygas M.

Zeszyty Problemowe Postępów Nauk Rolniczych

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1990

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tom 387

В труде определяли средние располагаемые расходы рек, являющиеся разницей между актуальным и нерушимым расходом для данного гидрометрического сечения реки.

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The Vistula River low flows in Warsaw in the 21st century

86%

Kaznowska E., Hejduk A., Kempinski C.

Acta Scientiarum Polonorum. Formatio Circumiectus

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2018

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tom 17

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nr 1

The aim of the paper is an analysis of low flows – a phenomenon of persistent low water levels and flows in the riverbed – of the Vistula River at the Warszawa-Nadwilanówka gauging station. The study concerned the beginning of the 21st century, against the 1951–2000 period. In order to determine the low flows on the daily flows hydrographs, they were cut-off by the threshold level method. According to the adopted criterion, low flows are rather rare on the Vistula in Warsaw. The longest and most severe drought in terms of outflow deficit occurred in 1951. In the last years of the studied period (2003, 2012, 2015), droughts have reached a considerable sizes, but were no greater than the low flow observed in 1951. Since 1985 no winter low flows have been recorded.

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Fisheries management of the welsh dee - A regulated river

86%

Hodgson B. P., O'Hara K.

Polskie Archiwum Hydrobiologii

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1994

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tom 41

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nr 3

5

Dominant discharge in the Indus river from downstream of the Kotri barrage dam

72%

Radecki-Pawlik A., Laszek W., Plesinski K., Khan Lashari B.

Acta Scientiarum Polonorum. Formatio Circumiectus

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2014

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tom 13

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nr 4

Hydraulic data of the Indus River, downstream of Kotri Barrage dam are analyzed. An attempt has been made to determine the dominant discharge, which is defined as that discharge which over a long time period transports the most sediments and could be used to predict the shape of river cross-section. For dominant discharge calculation Wolman and Miller’s approach has been applied. Since the transport of sediment concentration could be a more effective variable for forming the shape of the river cross-section, suspended sediment concentration has been introduced, because more than 85% of total load is in suspension. We show in the paper that water discharge Q = 1000 m³ · sˉ¹ of water is a frequent discharge and carries maximum sediment load. This discharge we call here the dominant discharge (Qdd) for the Kotri dam cross section.

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Statistical characteristics of riverflow variability in the Odra River basin, Southwestern Poland

72%

Sen A. K., Niedzielski T.

Polish Journal of Environmental Studies

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2010

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tom 19

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nr 2

387-396

We have analyzed the statistical characteristics of riverflow variability in the Odra River basin in southwestern Poland. In particular, we have examined the daily discharge time series recorded at 15 sites from November 1971 to October 2006. The skewness and kurtosis values of the time series are computed to determine if the empirical distribution of the data follows a normal distribution. The empirical distributions of all the time series are found to be non-Gaussian. The kurtosis values are interpreted in terms of intermittency, and together with skewness they are found to be significantly correlated with morphometric properties of the subbasins. In addition, several theoretical probability distributions are fitted to the riverflow data at each site. Among them, the 5-parameter Wakeby distribution is found to provide the best overall fit. Subsequently, the Wakeby distribution is used to calculate the return periods. Finally, the trend and stationarity around a trend of the various riverflow time series are assessed using the Cox-Stuart and Phillips-Perron (Dickey-Fuller) statistical tests. A decreasing trend is found in the daily discharge data at all sites, but there is no evidence of nonstationarity around the trend over the time span of the data record. A good understanding of the statistical characteristics of riverflow fluctuations in the Odra River basin is essential for water resources planning and management, including flood control and prediction in SW Poland.

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Reconstruction of retention capacity of small river basins as a protection measure against floods and droughts

72%

Mioduszewski W.

International Agrophysics

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1998

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tom 12

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nr 4

8

Flow velocity fluctuations and turbulence intensity over rough bed and bed covered with ligneous water plants

72%

Bartnik W., Florek J., Struzynski A., Schoberl F.

Electronic Journal of Polish Agricultural Universities. Series Environmental Development

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2004

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tom 07

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nr 1

Velocity fluctuations and turbulence of velocity in mountain rivers varys when the flow parameters change from free flow conditions to clogged cross-section. The first part of the paper is devoted to extending the description of turbulence intensity distribution in rough flow conditions. In the second part the effect of growth of ligneous water plants in the bed on turbulence intensity is presented.

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Investigation of droughts in the Lankaran region of Azerbaijan

58%

Imanov F. A., Mammadov A. S., Hasanova N. I.

Journal of Water and Land Development

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2012

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nr 16

10

The heavy metal accumulation in flood facies deposits in relation to morphology of the Vistula valley between Annopol and Gołab

58%

Falkowska E., Falkowski T.

Annals of Warsaw Agricultural University. Land Reclamation

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2005

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tom 36

11

Ocena trendu zmian reżimu hydrologicznego małej rzeki nizinnej

58%

Kanclerz J., Murat-Blazejewska S., Sojka M.

Zeszyty Problemowe Postępów Nauk Rolniczych

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2010

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tom 548

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nr 1

W pracy przedstawiono ocenę zmian wielkości i dynamiki przepływu małej rzeki nizinnej w wieloleciu 1987-1995 i 2007-2009. Ocenę dokonano na podstawie ciągłych (codziennych) i cyklicznych (1 raz w miesiącu) pomiarów natężenia przepływów Strugi Dormowskiej w profilu Gorzyń. Na podstawie codziennych pomiarów stanów wody i obliczonych przepływów rzeki w profilu Gorzyń w wieloleciu 1987-1995 ustalono, że średnie miesięczne przepływy były istotnie (na poziomie α = 0,05) zależne od miesięcznych sum opadów atmosferycznych. Z zależności tej na podstawie sum miesięcznych opadów określono średnie miesięczne przepływy w latach 2007-2009 i porównano z wartościami przepływów pomierzonych z częstotliwością jeden raz w miesiącu. Różnica pomiędzy pomierzonymi a obliczonymi średnimi miesięcznymi przepływami wynosiła ± 9%. Wskaźnik zaburzenia reżimu wynikającego z istotnych zmian w zagospodarowaniu zlewni obliczony jako bezwzględną wartość dopełnienia do jedności stosunku przepływu SSQ z ostatnich lat (2007-2009) i przepływu SSQ z wielolecia wcześniejszego (1987-1995) wyniósł 17%, co świadczy o niewielkim zaburzeniu reżimu hydrologicznego Strugi Dormowskiej.

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Changes in flood risk impacted by river training - case study of piedmont section of the Vistula river

58%

Lajczak A.

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

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2014

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tom 46

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nr 4

Main problems concerning the flood risk in piedmont section of the Vistula, Southern Poland, are discussed. This stretch of the river is channelized since the middle of the 19th century. It is part of the mainstream discussion of the effectiveness of existing river channelization methods. The following problems are analysed: (1) current state of flood risk, (2) the rate of river fl ow, (3) changes in flood risk since the start of channelization efforts with respect to changing channel geometry and changing rates of river flow reflecting the effects of channelization work. Substantially increased bankfull discharge in a channelized river may be considered as a stable hydrologic feature of the river stretch analysed. This means that the river is effectively reducing the quantity of water available for flooding the inter-embankment zone. This statement is the basis for analysis of changes in flood risk in the river studied. An assessment of changes in flood risk for the piedmont section of the Vistula cannot be categorical. Some changes in discharge help reduce flood risk, while others increase it. The paper is based mainly on the State Hydrological Survey data over more than the last 100 years, a large-scale maps over the last 230 years, and fieldwork conducted by the author.

Ograniczanie wyników

Flow characteristics of intermittent rivers in Slovakia

Przepływy dyspozycyjne rzek Pomorza

The Vistula River low flows in Warsaw in the 21st century

Fisheries management of the welsh dee - A regulated river

Dominant discharge in the Indus river from downstream of the Kotri barrage dam

Statistical characteristics of riverflow variability in the Odra River basin, Southwestern Poland

Reconstruction of retention capacity of small river basins as a protection measure against floods and droughts

Flow velocity fluctuations and turbulence intensity over rough bed and bed covered with ligneous water plants

Investigation of droughts in the Lankaran region of Azerbaijan

The heavy metal accumulation in flood facies deposits in relation to morphology of the Vistula valley between Annopol and Gołab

Ocena trendu zmian reżimu hydrologicznego małej rzeki nizinnej

Changes in flood risk impacted by river training - case study of piedmont section of the Vistula river