Wyniki wyszukiwania - Biblioteka Nauki

1

Critical velocities for non-cohesive grounds

100%

Zelazo J.

|

tom 23

2

Effects of human impact on the beds of minor watercourses of the Aegean Island of Icaria (Greece)

86%

Tsermegas I.

Quaestiones Geographicae

|

2012

|

tom 31

|

nr 1

3

Morphological features of river channels and floodplains in the Far East of Russia under various natural conditions

86%

Chernov A. V.

Geography and Tourism

|

2018

|

tom Vol. 6, No. 1

55--59

EN

Geographical analysis of river channel processes in rivers located along the meridional transect, running from the Arctic Ocean coast to Tibet and the East China Sea, confirmed that fluvial processes dominate in the formation of morphology and dynamics of river channels and floodplains in all natural zones and under different conditions of channel deformation development. However, even a small disturbance in “climate” conditions by other exogenous geomorphological processes changes the morphology and dynamics of channels and floodplains as well as the dynamics of fluvial processes. The effect of zonal factors depends on the size of a given river and is more pronounced in medium and small rivers than the large ones. Furthermore, the effect of zonal factors on the processes of river channels and floodplains depends on specific environmental conditions of the climate zones: the more extreme the manifestation of certain climatic phenomena, the more pronounced they are in the morphology and dynamics of river channels and floodplains.

4

Analysis of riverbed transformation in the long term on the examples of the tributaries of the upper Vistula river

86%

Lapuszek M.

|

nr 2/IV

5

Identification of vegetation parameters for compound channel discharge as inverse problem

86%

Kiczko A. , Koziol A. , Kubrak J. , Krukowski M. , Kubrak E. , Brandyk A.

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

|

2017

|

tom 49

|

nr 4

6

Effects of cypress knee roughness on flow resistance and discharge estimates of the Turkey Creek watershed

86%

Miroslaw-Swiatek D. , Amatya D. M.

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

|

2017

|

tom 49

|

nr 3

7

Changes of the morphology of the Ropa river — upstream and downstream of the Klimkówka water reservoir

86%

Wiejaczka Ł. , Kiszka K. , Bochenek W.

Studia Geomorphologica Carpatho-Balcanica

|

2014

|

tom Vol. 48

61--76

EN

The paper outlines changes in the channel morphology of the Ropa riverbed over the last six years, taking into account the role of large floods and the Klimkówka water reservoir in shaping the morphology of the riverbed. The analysis was based on annual geodetic measurements of the Ropa riverbed conducted between 2009–2014. The research was carried out in four cross profiles of the riverbed located upstream (1 profile) and downstream (3 profiles) of the reservoir. In order to recognise the direction and scale of morphology changes of the riverbed, additional analyses of water levels in the Ropa River was performed in the analysed multiannual period. The conducted analysis led to the conclusion that floods with extremely large discharges are the key factor causing the deepening of the riverbed downstream from the reservoir. It can be up to about 70 cm deep during a single event. The reservoir is just one additional factor of many which shape the direction and scale of changes to the riverbed. A significant role in modifying the riverbed morphology upstream from the reservoir is played by river control works, which diminish the effects of sediment accumulation occurring on this section.

8

Sentinel-2 nowe źródło danych w badaniach koryt rzecznych

86%

Kryniecka K. , Magnuszewski A.

|

tom Nr 7

13--18

PL

Zmiany morfologiczne zachodzące w korytach rzek są dynamiczne i wymagają monitorowania. Skutecznym sposobem śledzenia dynamiki zmian są analizy obrazów satelitarnych, które pozwalają na określenie geometrii form korytowych i tempa ich deformacji. W pracy omówiono źródła danych satelitarnych, w tym także tworzony przez IMGW-PIB portal „Sat4Envi". Przedstawione zostały parametry techniczne misji satelitarnej Sentinel-2 (rozdzielczość radiometryczna, spektralna, przestrzenna i czasowa), a także możliwości zastosowania zdjęć optycznych. Jako przykład w badaniach form korytowych pokazano wskaźniki teledetekcyjne NDWI, MNDWI, AWEInsh, AWEIsh, LSWI, MLSWI, SWM, obliczone na podstawie obrazu Sentinel-2 zarejestrowanego w dniu 5/09/19. Celem analizy jest wyróżnienie form korytowych w wybranym odcinku koryta dolnej Wisły (km 816-828) w warunkach niskiego przepływu oraz analiza przemieszczenia form korytowych w ciągu roku. Wyniki pokazują przydatność danych satelitarnych do badania form korytowych dużych rzek.

EN

Morphological changes occurring in riverbeds are dynamic and need to be monitored. An effective method of following the dynamics of such changes are satellite image analyses, which allow for determination of the riverbed forms geometry and their deformation rate. The article discusses the sources of satellite data, including the Sat4Envi portal created by the Institute of Meteorology and Water Management - National Research Institute. It presents technical parameters of the Sentinel-2 satellite mission (radiometric, spectral, spatial and temporal resolution), as well as the possibility to use optical photographs. As an example of data used in research on riverbed forms, the authors discuss the NDWI, MNDWI, AWEInsh, AWEIsh, LSWI, MLSWI and SWM remote sensing indexes, calculated based on the Sentinel-2 image recorded on 05/09/2019. The aim of the analysis is identification of riverbed forms in the selected section of the lower Vistula River (km 816-828) in low flow conditions and an analysis of riverbed forms movement throughout the year. The results show the useful char- acter of satellite data in research on large riverbed forms.

9

Turbulent kinetic energy of water in a compound channel

86%

Koziol A. P.

|

2011

|

tom 43

|

nr 2

10

Ostracoda (Crustacea) of the river bed in the lower course of a large lowland river system exemplified by the Oder River (Poland)

72%

Szlauer-Lukaszewska A. , Kowaluk-Jagielska B.

Zeszyty Naukowe. Acta Biologica. Uniwersytet Szczeciński

|

2011

|

tom 18

EN

The study was carried out in the main branches of the Lower Oder River, differentiated in terms of sediments composition. The aim was performing a comparative studies on the differences in Ostracoda fauna inhabiting various types of sediments. Following bottom sediments were distinguished: hard, sapropel/hard, sapropel and Chironomidae mat. The packet of CANOCO v.4.5 programs was used to investigate the interdependence between the species composition and environmental parameters. Eighteen taxa were found of which 16 were identified to the species level. It was a comparatively high number considering the fact that the samples were collected exclusively from the benthic zone and solely from the main river bed, without floodplain. Physocypria kraepelini was an eudominant and Darwinula stevensoni and Cypria ophtalmica were dominants. The samples collected from the sapropel were characterised by the highest density. The case of hard sediments the status of domination was retained as above, but there appeared a new dominant, i.e. Potamocypris unicaudata . The most unique structure of domination was observed in the case of Chironomidae mat, with Limnocythere inopinata as an eudominant and Cypridopsis vidua and P. unicaudata as dominants. As for the species diversity, the hard sediments were characterised by the highest value of Shannon-Wiener Diversity Index, the sapropel/hard sediment was the lowest. The type of river bottom to a great extent affects the density and taxonomic composition of the Ostracoda in rivers. The waters of the Oder River, rich in oxygen, provide favourable conditions for the development of ostracods even on the surface of sapropel sediment.

11

Sklad uziarnienia rumowiska jako wskaznik lokalnej degradacji koryta rzecznego

72%

Ksiazek L. , Michalik A. , Sladowski T.

Acta Scientiarum Polonorum. Formatio Circumiectus

|

2008

|

tom 07

|

nr 4

3-12

12

The upper Odra as a case study of the impact of channel regulation on its morphodynamics

72%

Czajka A.

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

|

2014

|

tom 46

|

nr 4

EN

The aim of the research was to compare morphodynamics of the Odra river channel in three different sectors and to fi nd the main difference in the way of sediment transport before and after regulation in meandering, straight and sinuous channel sectors and compare the data with those calculated for reconstructed, natural channel of the Odra river. Sediment transport in discussed sectors was compared for average, bankfull and fl ood discharges and it proceeds in different ways. Morphodynamics of the preregulated Odra was most similar to the one currently observed in the meandering section. Also the dynamics of bed-material transport and, consequently, the possibility of the occurrence and disappearance of channel forms is greatly varied among the studied sectors. As it was assumed, a diversifi ed channel geometry imposes water fl ow, which entails a series of processes shaping the channel dynamics.

PL

Celem badań jest porównanie morfodynamiki koryta Odry w trzech różnych odcinkach w celu wychwycenia różnic w sposobie transportu materiału przed regulacją i po regulacji koryta w odcinkach meandrującym, prostym i krętym oraz porównanie uzyskanych danych z danymi otrzymanymi dla koryta przedregulacyjnego. Transport materiału w omawianych odcinkach był porównywany dla przepływów średnich, pełnokorytowych i powodziowych. Morfodynamika przedregulacyjnego koryta Odry była najbardziej podobna do obecnie obserwowanej w korycie meandrowym. Dynamika transportu materiału dennego, a w konsekwencji powstawanie i rozmywanie form korytowych jest zróżnicowane w badanych odcinkach. Zgodnie z założeniami wykazano, że zmodyfi kowana geometria koryta Odry różnicuje przepływ wody, co z kolei pociąga za sobą różnice we współczesnych procesach kształtowania koryta.

13

The change in the economic use of the river valley area of the Krzna as a result of riverbed regulation

72%

Zbucki L. , Bujalski T.

|

2018

|

tom 11

|

nr 4

EN

Subject and purpose of work: This article identifies changes in the economic use of the river valley area of the Krzna, which occurred as a consequence of the regulation of its bed from the Klukówka estuary to the estuary of the Krzna to the Bug. Materials and methods: The analysis was carried out on the basis of cartographic maps and aerial photographs, as well as statistical analyses for the period 1931-2015. Results: The study confirmed the changes in the economic use of the valley of the Krzna River for the agricultural exploitation of the area and increasing crop yields. The biggest changes encompassed wetlands and swamps, mainly in favour of grasslands, whose area increased by 566%, to 2475.7 ha. Conclusions: The regulatory work carried out resulted in an increase in arable land, forests and areas for development, as well as in the reduction of water surface area from 251.94 ha in 1931 to 57.28 ha in 2015.

PL

Przedmiot i cel pracy: W niniejszym artykule określono zmiany gospodarczego użytkowania terenu w dolinie rzeki Krzny, które nastąpiły pod wpływem regulacji jej koryta od ujścia Klukówki do ujścia rzeki do Bugu. Materiały i metody: Analizy dokonano na podstawie map kartograficznych i zdjęć lotniczych oraz analiz statystycznych dla okresu 1931-2015. Wyniki: Przeprowadzone badania potwierdziły zmiany gospodarczego użytkowania terenu w dolinie rzeki Krzny na rolnicze wykorzystanie terenu i zwiększenie plonów. Największe zmiany objęły tereny podmokłe i bagienne głównie na rzecz użytków zielonych, których powierzchnia wzrosła o 566% do 2475,7 ha. Wnioski: Przeprowadzane prace regulacyjne spowodowały wzrost pól uprawnych, lasów i pojawienie się terenów pod zabudową oraz zmniejszenie powierzchni lustra wody z 251,94 ha w 1931 roku do 57,28 ha w 2015 roku.

14

Dynamics of water flow on degraded sectors of Polish mountain stream channels

72%

Michalik A. , Ksiazek L.

Polish Journal of Environmental Studies

|

2009

|

tom 18

|

nr 4

665-672

EN

Our study is aimed at determining the hydrodynamic changes of mountain stream channels caused by degradation that was initiated by uncontrolled mining of bed material. The study was conducted on Mszanka and Targaniczanka streams in which the collected data included: longitudinal profiles, cross-sections of the channels, the geometry of bed forms and analysis of particle composition of the bed material. The results show that hydrodynamic parameters have changed downstream from the studied sectors and along the cross-sections. Bed degradation also was linked to bank erosion, which intensified morphological changes of channels effecting the spatial distribution of flow velocity, shear stresses and stream power. The investigation also demonstrated that the bedload movement was in accordance with channel changes and more sediments were deposited than transported along the studied area. Finally, local aggradation and unstable channel capacity were observed.

15

Effects of environmental changes and human impact on the functioning of mountain river channels, Carpathians, southern Poland

72%

Krzemien K. , Gorczyca E. , Sobucki M. , Liro M. , Lyp M.

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

|

2015

|

tom 47

|

nr 3

EN

In the northern slope of the Carpathian Mountains and in their foreland, river and stream channels have been significantly transformed by human impact. These transformations result from changing land use in river basins and direct interference with river channels (alluvia extraction, engineering infrastructure, channel straightening). Anthropogenic impacts cause signifi cant changes in the channel system patterns leading to increased impact of erosion. This mainly leads to the channelling of the fluvial system. This article reviews studies of structure and dynamics of Carpathian river channels conducted based on the methodology of collection of data on channel systems, developed in the Department of Geomorphology of the Institute of Geography and Spatial Management, Jagiellonian University.

PL

W Karpatach i na ich przedpolu ma miejsce współcześnie znaczące przeobrażanie koryt rzek i potoków głównie pod wpływem antropopresji. Przeobrażenia te są uwarunkowane zmianami użytkowania w dorzeczach oraz bezpośrednią ingerencją w korytach (eksploatacja rumowiska, zabudowa hydrotechniczna, prostowanie koryt). W wyniku oddziaływań antropogenicznych następują znaczące zmiany struktury systemów korytowych prowadzące do wzrostu znaczenia erozji. Prowadzi to głównie do skanalizowania systemu fluwialnego. Artykuł jest przeglądem badań nad strukturą i dynamiką koryt rzek karpackich opartych na metodyce zbierania informacji o całych systemach korytowych. Zastosowano raptularz i instrukcję wypracowaną w Zakładzie Geomorfologii Instytutu Geografii i Gospodarki Przestrzennej Uniwersytetu Jagiellońskiego.

16

Invertebrate and fish environmental preferences as the key factor for lowland riverbed biodiversity

72%

Oglecki P.

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

|

2008

|

tom 40

17

Applying laser scanning technology to studying alluvial flume-bed topography in laboratory conditions

72%

Kiraga M. , Razumnik M. , Popek Z. , Chmielewski L.

Acta Scientiarum Polonorum. Formatio Circumiectus

|

2018

|

tom 17

|

nr 4

EN

The aim of the research was to compare alluvial bed topography description in laboratory conditions using the “traditional”, currently applicable method with an original approach, based on LiDAR technology. LiDAR application in local scours shape investigation in based on the grounds of introducing the autonomic measuring module, which, placed above the bed on dedicated controllable arrangement of guideways, describes the landform as a cloud of coordinates. The result of the performed experiment was obtainment of point clouds (x, y, z), reflecting the bed shape before and after local scour formation during twenty measurement series with varying hydraulic conditions. Objects of the study were basic geometry properties of the scour hole and its volume. The measurement with laser scanner technology application allowed for obtaining much more accurate results in shorter time, comparison to disc probe survey, and also relatively fast conversion of numerical data into figures. The device equipped with portable computer, precise stepper motors and dedicated software permitted the introduction of automation into laboratory work. The effect is not only measurements accuracy, but also significant acceleration of data gathering. The adopted grid is characterized by significant density, which – in connection with meaningfully high accuracy – allows very precise surface description. Bed shape can be presented in numerical or graphical form. It must be pointed out that disc probe method application would never give such accuracy as in the case of introducing laser scanning technology in similar studies.

PL

Praca badawcza ma na celu porównanie wyników ukształtowania dna piaszczystego w warunkach laboratoryjnych otrzymanych metodą tradycyjną oraz z użyciem autorskiego rozwiązania, opierającego się na technologii LiDAR. Zastosowanie technologii LiDAR w pomiarach kształtu i objętości rozmycia dna koryta laboratoryjnego opiera się na wprowadzeniu automatycznego modułu pomiarowego, który umieszczony powyżej dna koryta na specjalnie przegotowanym sterowalnym układzie prowadnic, opisuje jego kształt za pomocą chmury punktów. Efektem przeprowadzonych badań było otrzymanie chmur punktów (x, y, z), odzwierciedlających położenie dna przed i po uformowaniu się lokalnego rozmycia w dwudziestu seriach pomiarowych o zróżnicowanych warunkach hydraulicznych. Przedmiotem badania były podstawowe parametry geometryczne wybojów oraz jego objętość. Pomiar z użyciem skanera pozwolił na uzyskanie w krótszym czasie znacznie dokładniejszego odwzorowania wysokościowego dna na odcinku rozmycia, w porównaniu z określonym na podstawie pomiaru wykonanego sondą, a także na stosunkowo szybkie przetwarzanie danych do formy graficznej. Urządzenie wyposażone w przenośny komputer, precyzyjne silniki krokowe oraz specjalne oprogramowanie pozwala na zautomatyzowanie pracy w warunkach laboratoryjnych. Efektem jest nie tylko duża dokładność pomiarów, ale i ich znaczne przyspieszenie. Założona siatka współrzędnych cechuje się dużą gęstością, co w połączeniu z dużą dokładnością pozwala na precyzyjny opis kształtu analizowanej powierzchni, która może być przedstawiona w sposób graficzny lub numeryczny. Stosując metodę ręcznego pomiaru położenia dna, trudno osiągnąć taką samą dokładność jak w przypadku automatycznego urządzenia wyposażonego w laser.

18

Variability of the river bed system and morphology in the region of the block ramp impact (the case of the Porebianka river)

72%

Plesinski K.

|

nr 1

EN

The paper presents the influence of block ramp on system and morphological riverbed. One of twentyfive block ramp structures, located in the Porębianka River and situated in the central part of the cascade, was chosen for testing. In the observed section of the river, high morphological variability of the riverbed was observed in the years 2010–2011, caused by freshets. Additionally, in one period, the morphological changes were also caused by river training work, consisting in repairing block ramps of increased roughness, which were destroyed during the freshets, as well as damaging involvement with the riverbed. Despite the anthropogenic impact on the river channel, the research has shown that the morphology of the riverbed is returning to its natural structures, which are characteristic of the braided rivers. This confirms the thesis that the block ramps of increased roughness cause differentiation in river morphology, and restoration of the braided character of the channel. Therefore, we can conclude that river defends itself against damaging human activity. In addition, the paper describes the beginning of the movement of the debris, for the grain of boulder located in the Porębianka River, in the hydrodynamic conditions persisting during field measurement series. These conditions were based on Shields’ diagram and the graph showing the relationship of threshold shear stress for the given grain diameter of boulders.

PL

W pracy przedstawiono wpływ bystrza o zwiększonej szorstkości na układ i morfologię koryta rzecznego. Do badań wybrano jedno z dwudziestu pięciu bystrzy znajdujących się w korycie rzeki Porębianki, usytuowane w środku kaskady. Na obserwowanym odcinku stwierdzono dużą zmienność morfologiczną koryta, która była spowodowana przechodzącymi na przestrzeni lat 2010–2011 falami wezbraniowymi. Dodatkowo, w pewnym okresie zmiany w układzie i morfologii koryta zaszły w skutek działania prac utrzymaniowych. Działania te polegały na naprawie uszkodzonych podczas wezbrania bystrzy o zwiększonej szorstkości, ale także i na niekorzystnej ingerencji w dno koryta rzecznego. Pomimo antropogenicznego wpływu na koryto, z przeprowadzonych badań wynika, że morfologia analizowanego koryta rzecznego powraca do swoich naturalnych struktur, które są charakterystyczne dla rzek roztokowych. Potwierdza to tezę, że bystrza o zwiększonej szorstkości powodują zróżnicowanie morfologii koryta rzecznego i odtworzenie jego roztokowego charakteru, a tym samym możemy stwierdzić, że rzeka ma tendencję do pewnego bronienia się przed szkodliwą działalnością człowieka. Ponadto w pracy określono początek ruchu rumowiska dla ziaren otoczaków znajdujących się w korycie Porębianki podczas hydrodynamicznych warunków zastanych przy pomiarach terenowych. Warunki te określono na podstawie wykresu Shieldsa i wykresu obrazującym graniczne naprężenie styczne dla danych średnic ziaren otoczaków.

19

Studies on riverbed erosion on the Raba river close to the Stroza gauging station

72%

Lapuszek M.

Infrastruktura i Ekologia Terenów Wiejskich

|

2011

|

nr 12

EN

The aim of the paper is to present the studies on the riverbed erosion on the upper course of Raba river, located from km 81.829 to km 77.751, close to the Stróża gauging station located in km 80.600. This part of the river course is completely changed due to the Project concerning the extension of the Zakopianka road located close to the Raba river. The results of simulation of riverbed evolution before and after the Project carried out by two 1D models (RubarBE and Metoda) are analysed and discussed. The results of computation obtained by both models are verified by field observations carried out in 2001 (before the Project), and in 2009 year (after the Project). The trends of erosion and deposition correspond to the field observations for the dates before and after the Project. Another verification is possible to make for the Stróża cross-section, where observations of cross-sectional geometry and water stages have been carried out from 1900 year till now. The statistical model of riverbed erosion developed for Stróża also confirm the trends obtained there by 1D models.

20

Pollution of Mala Panew River sediments by heavy metal: Part I. Effect of changes in river bed morphology

72%

Ciszewski D.

Polish Journal of Environmental Studies

|

2004

|

tom 13

|

nr 6

EN

Relations between changes in bed morphology and heavy metal concentrations were investigated in the Mała Panew River channel in southern Poland. Samples of bed sediments were collected at ten locations 12 times during two years. Concentrations of cadmium, zinc and lead in the river sediments are among the highest in Poland and in silt-clay fraction it reaches 600, 4000 and 500 ppm, respectively. At most channel locations, migration of one or two sand bars was observed. Usually a dead water zone, which was a particularly important sink for fine, strongly polluted organic sediments, appeared in front of the bar. Here, also the highest heavy metal concentrations occurred. The dead water existed usually for several months until it was destroyed by a flood or filled with sand sediments in the case of the bar front accretion. As a result, a marked drop of metal concentrations, accompanied by higher flow velocities, followed in a relatively short period.