Sediment Dynamics for



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Key words sediment budget; fluvial geomorphology; sediment transport

------------------------------------------------------------------------------------------------------------------------------------------------------Sediment Dynamics for a Changing Future (Proceedings of the ICCE symposium held at Warsaw University of Life Sciences - SGGW, Poland, 14–18 June 2010). IAHS Publ. 337, 2010, 129-136.

Overbank sedimentation rates on the flood plains of small rivers in Central European Russia
V. N. Golosov, V. R. Belyaev, M. V. Markelov & K. S. Kislenko

Laboratory of Soil Erosion and Fluvial Processes, Faculty of Geography, Moscow State University, GSP-1,
Leninskie Gory, 119991, Moscow, Russia


gollossov@rambler.ru
Abstract The spatial variation and temporal dynamics of overbank sedimentation rates were studied on the flood plains of five rivers located in different parts of the Central Russian Plain. The radioactive isotope 137Cs was used as a tracer for quantification of sedimentation rates. At least two morphologically typical flood plain segments were investigated along each of the rivers studied, with one sediment section sampled depth-incrementally at each of the studied segments to determine the 137Cs depth distribution. Both bomb-derived (1963–1964) and Chernobyl-derived (1986) 137Cs peaks could be reliably identified in most of the sections investigated. Thus, the vertical distribution of 137Cs in flood plain deposits permits the sedimentation rates for two relatively equal time intervals: 1964–1986 and 1986–present to be estimated. A clear trend of decreasing deposition rates is apparent for the last two decades. This can be attributed to recent land-use changes and climatic fluctuations.

Key words overbank sedimentation; flood plain; small rivers; drainage basin; 137Cs; European Russia

------------------------------------------------------------------------------------------------------------------------------------------------------Sediment Dynamics for a Changing Future (Proceedings of the ICCE symposium held at Warsaw University of Life Sciences - SGGW, Poland, 14–18 June 2010). IAHS Publ. 337, 2010, 137-142.

Deposition of overbank sediments within a regulated reach of the upper Odra River, Poland
AGNIESZKA CZAJKA1 & DARIUSZ CISZEWSKI2

1 Department of Earth Sciences, University of Silesia, Bedzinska 60, 41-200 Sosnowiec, Poland

agnieszka.czajka@us.edu.pl

2 Institute of Nature Conservation, Polish Academy of Science, Al. Mickiewicza 33, 31-120 Krakow, Poland
Abstract Rivers and their flood plains are in a state of flux. Due to agricultural, urban and industrial development, and river training works, the natural erosion and sedimentation processes of the Odra River were modified in the 19th century. The geometry of the river channel has changed drastically, and the rates of overbank sedimentation are relatively high when compared to rates calculated for natural conditions. The rates of overbank sedimentation were assessed using the heavy metal content in overbank deposits. Only sediments deposited directly along the pre-regulation channels were considered. Fluvial processes in the studied, trained river channel seem to be more intensive than in the natural channel. Overbank deposition in the studied reach of the Upper Odra changed from 1.3 to 1.8 cm year-1 in the 19th century to 2–5 cm year-1 at present, which means that the rate of over-bank sedimentation has increased up to 3-fold.

Key words flood plain sedimentation rates; regulated river; heavy metals; Odra River

------------------------------------------------------------------------------------------------------------------------------------------------------Sediment Dynamics for a Changing Future (Proceedings of the ICCE symposium held at Warsaw University of Life Sciences - SGGW, Poland, 14–18 June 2010). IAHS Publ. 337, 2010, 143-148.

Sediments of the Yenisei River: monitoring of radionuclide levels and estimation of sedimentation rates
ALEXANDER BOLSUNOVSKY & DMITRY DEMENTYEV

Institute of Biophysics SB RAS, Akademgorodok, 660036, Krasnoyarsk, Russia

radecol@ibp.ru
Abstract The Yenisei River, one of the largest rivers in the world, is contaminated with artificial radionuclides released by a Russian nuclear facility producing weapon-grade plutonium, which has been in operation for many years. Examination of Yenisei River sediment samples revealed the presence of artificial radionuclides typical of radioactive discharge from the Mining-and-Chemical-Combine (MCC) nuclear facility: isotopes of europium (152Eu, 154Eu, and 155Eu), caesium (137Cs and 134Cs), 60Co, 90Sr, and transuranium elements. Maximum radionuclide concentrations in sediments remained high as far as 240 km downstream of the MCC. In sediment cores collected upstream of the MCC, γ-spectrometric measurements registered only one artificial radionuclide, 137Cs, with a maximum activity of approx. 8 Bq kg-1 dry mass. Sediments of the Yenisei River also contain natural radionuclides. Sedimentation rates in several sections of the Yenisei River were determined using different approaches: the 210Pb dating method and the ratios of artificial radionuclides – 137Cs/60Co and 152Eu/154Eu. With increasing distance downstream of the city of Krasnoyarsk, sedimentation rates increased from 0.88 cm year-1 to 1.30–1.51 cm year-1.

Key words river sediments; artificial and natural radionuclides; sedimentation rates; dating methods; Yenisei River

------------------------------------------------------------------------------------------------------------------------------------------------------Sediment Dynamics for a Changing Future (Proceedings of the ICCE symposium held at Warsaw University of Life Sciences - SGGW, Poland, 14–18 June 2010). IAHS Publ. 337, 2010, 149-156.

Preliminary investigation of the potential for using the 137Cs technique to date sediment deposits in karst depressions and to estimate rates of soil loss from karst catchments in southwest China

X. B. ZHANG1,2, X. Y. BAI1 & A. B. WEN1

1 Key Laboratory of Mountain Environment Evolvement and Regulation, Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Sichuan 610041, China

baixiaoyong@126.com

2 State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, Guizhou 550002, China
Abstract Soil erosion plays an important role in land desertification in the karst mountain areas of southwest China, but reliable data on rates of surface soil loss in the area are very limited. Hill-depressions are common landforms in the karst areas. The 137Cs technique was used to date the sediment deposits in six karst depressions, to estimate average rates of surface soil loss from their catchments. The estimates of soil loss rates obtained from this study evidenced considerable variability. A value of 1.0 t km-2 year-1 was obtained for a catchment under original dense karst forest, but the erosion rates ranged between 19.3 t km-2 year-1 and 48.7 t km-2 year-1 in four catchments under secondary forest or grasses, where the original forest cover had been removed in the Ming and Qing dynasties, several hundred years ago. The highest rate of 1643 t km-2 year-1 was obtained for a catchment underlain by clayey carbonate rocks, where the soil cover was thicker and more extensive than in the other catchments and extensive land reclamation for cultivation had occurred during the period 1979–1981, immediately after the Cultural Revolution.

Key words karst depression; accumulated sediment; dating; caesium-137; soil loss; erosion rates

------------------------------------------------------------------------------------------------------------------------------------------------------Sediment Dynamics for a Changing Future (Proceedings of the ICCE symposium held at Warsaw University of Life Sciences - SGGW, Poland, 14–18 June 2010). IAHS Publ. 337, 2010, 157-162.

The assessment of natural and artificial radionuclides in river sediments in the Czech Republic
Diana Ivanovová1, Eduard Hanslík1 & Pavel Stierand2

1 T. G. Masaryk Water Research Institute, Public Research Institution, Podbabská 30, 160 00 Prague 6, Czech Republic

diana_ivanovova@vuv.cz

2 Czech Hydrometeorological Institute, Na Šabatce 17, 143 06 Prague 4, Czech Republic
Abstract The concentrations of natural radionuclides, radium­226, radium­228, and potassium-40, and the artificial radionuclide caesium-137, in river sediments were monitored in the Czech Republic by the Czech Hydrometeorological Institute during the period 2000–2008. The data were used to evaluate the natural background levels of these radionuclides and the impact of human activities on the water environment. The river sediments were identified as good indicators of radioactive contamination, especially radium­226 which recorded historic contamination due to former uranium mining and milling. The radium­226 contamination rate was assessed using the ratio of radium­226 to radium­228. This ratio was used to classify sediment according to the relative contamination from the uranium industry. The residual contamination of caesium-137 due to the Chernobyl accident in 1986 was also assessed.

Key words river sediments; surface water; uranium industry; radioactive contamination; radium­226; radium­228; potassium-40; caesium-137

------------------------------------------------------------------------------------------------------------------------------------------------------Sediment Dynamics for a Changing Future (Proceedings of the ICCE symposium held at Warsaw University of Life Sciences - SGGW, Poland, 14–18 June 2010). IAHS Publ. 337, 2010, 163-171.

Exploring the relationship between sediment and fallout radionuclide output for two small Calabrian catchments
PAOLO PORTO1,2, DESMOND E. WALLING1, GIOVANNI CALLEGARI3 & CARMELO LA SPADA2

1 Department of Geography, University of Exeter, Exeter, UK

p.porto@exeter.ac.uk

2 Dipartimento di Scienze e Tecnologie Agro-Forestali e Ambientali - Università degli Studi Mediterranea di Reggio Calabria, Italy

3 CNR – Istituto per i Sistemi Agricoli e Forestali del Mediterraneo, Sezione Ecologia e Idrologia Forestale, Rende (CS), Italy
Abstract In southern Italy, several investigations have documented values of soil loss greater than
100 t ha-1 year-1, especially when including periods with extreme rainfall events. There is an increasing need to develop an improved understanding of erosion and sediment delivery dynamics in this environment. The use of environmental radionuclides, particularly 137Cs and 210Pb, to investigate sediment dynamics at the catchment scale has been shown to possess several important advantages over conventional monitoring techniques, and can provide valuable information on the functioning of the erosion and sediment delivery system. The study reported here is based on two small catchments for which storm-period suspended sediment loads have been documented for a range of storm events. In addition to quantifying the storm-period sediment loads at the catchment outlets, information on the radionuclide content of the sediment output and the storm-period radionuclide fluxes has also been obtained. Surface soil samples were collected within the catchments, in order to document source material properties. The relationships between suspended sediment output and the radionuclide flux for individual storm events, as well as the variation of the 137Cs and 210Pb activity of the suspended sediment, have been explored in order to obtain an improved understanding of the sediment dynamics and functioning of the two catchments. This analysis has emphasized the close relationship between the storm-period sediment and radionuclide fluxes from the two catchments, which provides valuable confirmation of the validity of existing approaches for using environmental radionuclides to document soil erosion and soil redistribution rates.

Key words caesium-137; lead-210; soil erosion; suspended sediment; sediment delivery; erosion rates; Italy

------------------------------------------------------------------------------------------------------------------------------------------------------Sediment Dynamics for a Changing Future (Proceedings of the ICCE symposium held at Warsaw University of Life Sciences - SGGW, Poland, 14–18 June 2010). IAHS Publ. 337, 2010, 172-180.

Long-term monitoring of the 137Cs activity in suspended sediment transported by the Homerka stream, Polish Flysch Carpathians
Wojciech Froehlich1 & Des E. Walling2

1 Homerka Laboratory of Fluvial Processes, Institute of Geography and Spatial Organization,
Polish Academy of Sciences, Frycowa 113, 33-335 Nawojowa, Poland


wfroehlich@pro.onet.pl

2 School of Geography, University of Exeter, Amory Building, Rennes Drive, Exeter EX4 4RJ, UK
Abstract The work reported was undertaken in the Homerka instrumented catchment in the Polish Flysch Carpathians. The 137Cs activity of suspended sediment has been documented since 1984 using bulk samples of suspended sediment collected from the main gauging station and occasionally from tributaries during periods of flood discharge. The 134Cs content of the suspended sediment samples was also measured after the Chernobyl accident. Attention focuses on both the longer-term trends in radiocaesium activity and the shorter-term variations in the 137Cs content of suspended sediment during flood events. The longer-term variations in the 134Cs and 137Cs activity of suspended sediment is shown to reflect the interaction of fallout inputs, radiocaesium storage and remobilisation and radioactive decay, whereas the short-term variability is seen to be controlled by the complex interaction of sediment sources, catchment contributing areas and the sediment delivery dynamics.

Key words fallout radionuclides; caesium-134; caesium-137; bomb test; Chernobyl accident; suspended sediment sources; sediment delivery dynamics; Homerka catchment; Polish Flysch Carpathians

------------------------------------------------------------------------------------------------------------------------------------------------------Sediment Dynamics for a Changing Future (Proceedings of the ICCE symposium held at Warsaw University of Life Sciences - SGGW, Poland, 14–18 June 2010). IAHS Publ. 337, 2010, 181-188.

Sediment dynamics of glacier-fed rivers
JIM BOGEN

Norwegian Water Resources and Energy Directorate, PO Box 5091, Maj. 0301 Oslo, Norway

jbo@nve.no
Abstract The sediment dynamics of glacier-fed rivers differ from those of unglaciated catchments. Monitoring programmes in glacier-fed rivers demonstrate that their sediment dynamics have several distinctive characteristics, which are the focus of this paper. In the meltwater outflow from the Nigardsbreen glacier in Norway the seasonal variations in sediment response may be divided into three different periods. Sediment concentrations vary unpredictably in the first part of the runoff season. During the summer peak of glacier melting there is some dependency on water discharge, but observations show no obvious direct correlation that persists beyond a single flood event. During the period of autumn rainfall, the magnitude of the sediment concentration is controlled by the access of the runoff to the subglacial drainage system. High sediment concentrations may occur at the start of this period, but concentrations tend to fall as the subglacial conduits close. The pattern of variability of sediment concentrations may be interpreted in terms of a conceptual model, where sediment is introduced into the subglacial waterways by melting of debris-rich ice at the glacier sole. It is believed that the irregular fluctuations of sediment concentrations early in the season are associated with the establishment of a subglacial conduit system. Later in the season, flood discharges expand the conduits, melting ice and adding sediment to the meltwater. In periods of low water discharge, less sediment is added, but movement of the glacier and its plastic deformation will eventually expose more sediment-laden ice to melt-out processes. High concentrations most often occur towards the end of the glacier-melt period when floods are generated by a combination of rain and glacier melt. These rain floods drain through an open conduit system, melting out further sediment. The sediment transport from the polythermal Brøggerbreen glacier in the high Arctic was also studied. It was found that the low deformation rates in the cold ice of the subglacial drainage systems beneath polythermal glaciers make them more stable. Therefore a stronger correlation between sediment transport and water discharge may exist on an annual basis.

Key words suspended sediment; sediment dynamics; glacier fed rivers; subglacial drainage


------------------------------------------------------------------------------------------------------------------------------------------------------Sediment Dynamics for a Changing Future (Proceedings of the ICCE symposium held at Warsaw University of Life Sciences - SGGW, Poland, 14–18 June 2010). IAHS Publ. 337, 2010, 189-196.

Variations in suspended sediment grain sizes in flood events of a small lowland river
LESZEK HEJDUK & KAZIMIERZ BANASIK

Warsaw University of Life Sciences – SGGW, Department of Water Engineering and Environmental Restoration, Nowoursynowska 166, PL-02-787 Warsaw, Poland

leszek_hejduk@sggw.pl
Abstract The grain size of suspended sediment and its variation during river flows is important information required for the modelling of river sediment transport and reservoir siltation, as well as for understanding the role of sediment particles in a variety of environmental processes. In this study, the results of grain size analyses of suspended sediment transported during flood events in a small lowland river are presented. The investigated area is the agricultural catchment of the River Zagozdzonka, a tributary of the River Vistula, located in the centre of Poland, approx. 100 km south of Warsaw. A total of 160 suspended sediment samples were collected in the period 2004–2007 during 11 flood events, caused by rainfall, snowmelt or a combination of both, and the samples were analysed for their particle size distribution. Mean values of the d50 of the suspended sediment for the events varied from 48 μm to 98 μm, and there was a tendency for an increase in particle size with increasing discharge.

Key words suspended sediment; grain size distribution; discharge-grain size relation

------------------------------------------------------------------------------------------------------------------------------------------------------Sediment Dynamics for a Changing Future (Proceedings of the ICCE symposium held at Warsaw University of Life Sciences - SGGW, Poland, 14–18 June 2010). IAHS Publ. 337, 2010, 197-203.

The impact of road construction on suspended sediment and solute yields of headwater streams in northern Apennine, Italy
SAMANTA PELACANI, GIULIANO RODOLFI &
FIORENZO CESARE UGOLINI


Department of Soil Science and Plant Nutrition, P. le delle Cascine 15, I-50144 Florence, Italy

samanta.pelacani@unifi.it
Abstract We investigated suspended and dissolved loads of two streams which drain into the Bilancino reservoir, the principal water supply of Florence in Italy. In northern Apennine, headwater catchments have been affected by mass movements. In the Bilancino watershed, more than 50% of the landslides are directly connected with the streams, which otherwise tend to transport little sediment due to the presence of 89 check dams, one for each square kilometre. Suspended sediment was monitored for two years using time-integrated sediment traps. One stream, which was impacted by road construction, had a suspended sediment yield of 116 t km-2 year-1, while a nearby non-impacted stream had a yield of 14 t km-2 year-1. The stream water chemistry was also affected by the highway construction, which has produced spoils containing albite and Na-bearing olistostrome. The calculated cation flux was 416 t km-2 year-1 for the impacted watershed and 210 t km-2 year-1 for the non-impacted one.

Key words suspended sediment yields; sedimentation; suspension flows; solute yields; headwater catchments

------------------------------------------------------------------------------------------------------------------------------------------------------Sediment Dynamics for a Changing Future (Proceedings of the ICCE symposium held at Warsaw University of Life Sciences - SGGW, Poland, 14–18 June 2010). IAHS Publ. 337, 2010, 204-210.

Historic sediment yields in a small ungauged catchment controlled by a warping dam, using sediment deposition information and 137Cs dating
LI ZHAN-BIN1, LU KE-XIN1, HOU JIAN-CAI2 & LI MIAN3

  1. Key Laboratory of Northwest Water Resources and Environmental Ecology of Ministry of Education,
    Xi’an University of Technology, Xi’an, Shaanxi, 710048, China


zhanbinli@126.com

2 Department of Water Resources of Henan Province, Zhengzhou 450003, China

3 Key Laboratory of Sediment Research of Yellow River, Yellow River Institute of Hydraulic Research,
Zhengzhou 450003, China

Abstract In the hilly and gully region of the Loess Plateau, China, warping (check) dams are one of the most important engineering measures for controlling soil and water loss, and reducing downstream sediment yields. Based on detailed field observations, the sediment profile upstream of the third warping dam, located in a small ungauged watershed (Guandigou) of the Wangmaogou catchment, was divided into 31 sedimentary layers, and the sediment thickness and 137Cs activity of each layer were measured. Peaks in 137Cs activity in the sediment layers were equated to 1963 (peak in fallout) and 1986 (Chernobyl incident). These dated layers, in combination with historical information on erosive rainstorm events, were used to date the timing of sediment deposition for each layer. Based on the information on sediment thickness for the 31 layers, and field measurements of the surface area of each layer, the specific sediment yields from 1959 to 1987 were estimated. The results indicated that the approach, i.e. the combination of 137Cs dating and the sediment record deposited upstream of a warping dam, could be used to study soil erosion and deposition in small ungauged watersheds in the Loess Plateau region of China.

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