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Erosion and Sediment Yields in the Changing Environment Edited by Adrian L. Collins, Valentin Golosov, Arthur J. Horowitz, Xixi Lu, Mike Stone, Des E. Walling & Xinbao Zhang IAHS Publ. 356 (2012) ISBN 978-1-907161-33-9, 452 + x pp. Price £90.00 The ICCE-2012 symposium, held in Chengdu, China, continued the highly successful, ongoing series of ICCE symposia and publications, and focused on understanding of the processes of erosion and sediment production in a world that is increasingly affected by anthropogenic activities. Four keynote papers open this volume, and the remaining 50 contributions are grouped by theme:  Dynamic processes of erosion and sediment transport in fluvial systems  Impacts of climate change and human activities on erosion and sediment yield  Modelling erosion and sediment yields  Mountain hazards and debris flows  Monitoring and tracing methodology

Abstracts of the papers in this volume can be seen at: www.iahs.info

Preface

Since the early 1980s, the International Commission on Continental Erosion (ICCE) of the International Association of Hydrological Sciences (IAHS) has organized a large number of highly successful symposia and workshops dealing with various aspects of erosion and sedimentation. The proceedings of most of these symposia and workshops have been published as IAHS “Red Books” (see over for details, or go to http://www.iahsmembers.info/shop.php). The Chengdu symposium on Erosion and Sediment Yields in the Changing Environment represents a continuation of this highly successful, ongoing series of ICCE symposia, and the papers have been pre-published in this IAHS Red Book. The response to the “call for papers” for this symposium generated 90 abstracts, which may well provide an indication of the increasing significance of soil erosion and sediment yield issues to both the environmental as well as the scientific communities. The 54 papers published in this volume, including four keynote papers, aim to advance our understanding of the processes of erosion and sediment production in a world that is increasingly affected by anthropogenic activities, and to encourage further work. The keynote papers have been placed at the beginning of the volume and the remaining papers have been grouped under five main themes. The group of papers on Dynamic processes of erosion and sediment transport in fluvial systems provides information on the pathways and patterns of erosion and sediment transport in fluvial systems. Another group of papers dealing with Impacts of climate change and human activities on erosion and sediment yield is primarily concerned with the influence of land-use change on catchment soil erosion and sediment yields and fluxes. The group dealing with Modelling erosion and sediment yields covers a wide variety of approaches for estimating sediment concentrations/fluxes in the absence of actual sample data. The papers grouped under the theme of Mountain hazards and debris flows provide information on quantifying and modelling landslides and debris flows in different countries/environments. The fifth group of papers dealing with Monitoring and tracing methodology highlights the important role of both monitoring and tracing approaches for improving our understanding of soil erosion and sedimentation. We hope that these contributions will encourage further research on how erosion and sediment yields respond to changing environments and climatic conditions in what is becoming known as the Anthropocene.

EDITORS Adrian L. Collins ADAS, Pendeford House, Wobaston Road, Wolverhampton WV9 5AP, UK Valentin Golosov Faculty of Geography, Lomonosov Moscow State University GSP-1, 119991, Leninskie Gory 1, Moscow and Kazan Federal University, Kremlevskaya st., 18, Kazan, Russia Arthur J. Horowitz US Geological Survey, Peachtree Business Center, 3039 Amwiler Road, Atlanta, Georgia 30360, USA Xixi Lu Department of Geography, National University of Singapore, 10 Kent Ridge Crescent, 119260, Singapore Mike Stone Department of Geography and Environmental Management, University of Waterloo, Ontario N2L 3G1, Canada Des E. Walling College of Life and Environmental Sciences, University of Exeter, Exeter EX4 4RJ, UK Xinbao Zhang Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu, 610041, China

IAHS publications resulting from ICCE symposia and workshops

Erosion and Sediment Transport Measurement, Florence, Italy, 1981 (IAHS Publ. 133) Recent Developments in the Explanation and Prediction of Erosion and Sediment Yield, Exeter, UK, 1982 (IAHS Publ. 137) Dissolved Loads of Rivers and Water Quantity/Quality Relationships, Hamburg, Germany, 1983 (IAHS Publ. 141) Drainage Basin Sediment Delivery, Albuquerque, New Mexico, USA, 1986 (IAHS Publ. 159) Erosion, Transport and Deposition Processes, Jerusalem, Israel, 1987 (IAHS Publ. 189) Sediment Budgets, Porto Alegre, Brazil, 1988 (IAHS Publ. 174) Sediment and the Environment, Baltimore, USA, 1989 (IAHS Publ. 184) Erosion, Debris Flows and Environment in Mountain Regions, Chengdu, China, 1992 (IAHS Publ. 209) Erosion and Sediment Transport Monitoring Programmes in River Basins, Olso, Norway, 1992 (IAHS Publ. 210) Sediment Problems: Strategies for Monitoring Prediction and Control, Yokohama, Japan, 1993 (IAHS Publ. 217) Variability in Stream Erosion and Sediment Transport, Canberra, Australia, 1994 (IAHS Publ. 224) Effects of Scale on the Interpretation and Management of Sediment and Water Quality, Boulder, USA, 1995 (IAHS Publ. 226) Erosion and Sediment Yield: Global and Regional Perspectives, Exeter, UK, 1996 (IAHS Publ. 236) Human Impact on Erosion and Sedimentation, Rabat, Morocco, 1997 (IAHS Publ. 245) Modelling Soil Erosion, Sediment Transport and Closely Related Hydrological Processes, Vienna, Austria, 1998 (IAHS Publ. 249) Role of Erosion and Sediment Transfer in Nutrient and Contaminant Transfer, Waterloo, Canada, 2000 (IAHS Publ. 263) Erosion and Sediment Transport Measurement in Rivers: Technological and Methodological Advances, Oslo, Norway, 2002 (IAHS Publ. 263) The Structure, Function and Management Implications of Fluvial Sedimentary Systems, Alice Springs, Australia, 2002 (IAHS Publ. 276) Erosion Prediction in Ungauged Basins: Integrating Methods and Techniques, Sapporo, Japan, 2003 (IAHS Publ. 279) Sediment Transport through the Fluvial System, Moscow, Russia, 2004 (IAHS Publ. 288) Sediment Budgets, vols 1 and 2, Foz do Iguaçu, Brazil, 2005 (IAHS Publs 291 and 292) Geomorphological Processes and Human Impacts in River Basins, Solsona, Spain, 2004 (IAHS Publ. 299) Sediment Dynamics and the Hydromorphology of Fluvial Systems, Dundee, UK, 2006 (IAHS Publ. 306) Water Quality and Sediment Behaviour of the Future: Predictions for the 21st Century, Perugia, Italy, 2007 (IAHS Publ. 314 Sediment Dynamics in Changing Environments, Christchurch, New Zealand, 2008 (IAHS Publ. 325) Sediment Dynamics for a Changing Future, Warsaw, Poland, 2010 (IAHS Publ. 337) Sediment Problems and Sediment Management in Asian River Basins, Hyderabad, India, 2009 (IAHS Publ. 349) Wildfire and Water Quality: Processes, Impacts and Challenges, Banff, Canada, 2012 (IAHS Publ. 354)

* IAHS Publ. 133 refers to the publication number in the IAHS Proceedings and Reports series (the Red Books). Details of these publications are available at http://www.iahs.info/redbooks.htm. Volumes published before 2005 (Publs 1 to 290) can be downloaded as pdf files from the website without charge. More recent ones can be purchased from the IAHS Bookshop at www.iahs.info.

Contents Preface by Adrian L. Collins, Valentin Golosov, Arthur J. Horowitz, Xixi Lu, v Mike Stone, Des E. Walling & Xinbao Zhang

1 Keynote Papers

The role of dams in the global sediment budget 3 Des E. Walling Redistribution of sediment and sediment-associated contaminants in the River Chern 12 basin during the last 50 years Valentin Golosov, Elena Aseeva, Vladimir Belyaev, Maxim Markelov & Alisa Alyabieva Delineation of China’s reservoirs and lakes using remote sensing techniques 20 Xixi Lu, Xiankun Yang & Lishan Ran Impacts of eco-restoration on suspended sediment load in the upper Yangtze River, China 29 He Xiubin & Wei Jie

2 Dynamics of Erosion and Sediment Transport in Fluvial Systems Annual fluxes of sediment-associated trace/major elements, carbon, nutrients and sulfur 39 from US coastal rivers Arthur J. Horowitz, Verlon C. Stephens, Kent A. Elrick & James J. Smith Transport of suspended sediment by the Vistula River basin upstream of Kraków, 49 southern Poland, and the human impact during the second half of the 20th century Adam Łajczak Dynamics of bank erosion on the River Dane, England 57 Janet Hooke An update of the magnitude–frequency analysis of Rio Cordon (Italy) bedload data after 65 25 years of monitoring L. Picco, L. Mao, E. Rigon, J. Moretto, D. Ravazzolo, F. Delai & M. A. Lenzi Sediment transport in the proglacial Fagge River (Kaunertal/Austria) 72 David Morche, Florian Haas, Henning Baewert, Tobias Heckmann, Karl-Heinz Schmidt & Michael Becht Sediment and water quality in the Kam Tin River, Hong Kong 81 M. R. Peart, L. Fok & J. Chen Dynamics of sediment delivery in drain flow on clay soils across England and Wales 91 Yusheng Zhang, Adrian L. Collins & John R. Williams Suspended sediment transport by rivers in the different climatic zones of Cameroon 98 (Central Africa) Gaston Lienou, Gil Mahe, Luc Sigha-Mkamdjou, Jean Emmanuel Paturel, Jacob Nwalal & Justin Nlozoa Are riverine sediment discharges sufficient to offset the sinking coast of Louisiana? 104 Y. Jun Xu & Timothy Rosen Sediment quality in the water-level-fluctuation-zone of the Three Gorges Reservoir, China 114 Zhijing Cao & Yuhai Bao 3 Impacts of Climate Change and Human Activities on Erosion and Sediment Yield

Assessing “modern background sediment delivery to rivers” across England and Wales 125 and its use for catchment management Adrian L. Collins, Ian Foster, Yusheng Zhang, Richard Gooday, David Lee, David Sear, Pamela Naden & Iwan Jones Transient storage and release of sediment and phosphorus in a small urban impoundment 132

N. McLellan, L. Gray, D. Allin, K. Damude, A. DiFebo, K. McLean, E. Sararas, M. Stone & J. Price Landslide impacts on suspended sediment sources following an extreme event in the 138 Magela Creek catchment, northern Australia Wayne D. Erskine & Michael J. Saynor Driving forces in a floodplain restoration project: interaction between surface water, 146 groundwater and morphodynamic processes during an ecological flooding Peter Fischer, Florian Haas & Bernd Cyffka Fractal geometry of aggregates in natural grassland soils with different restoration stages 155 Zhou Ping, Wen Anbang, Zhuang Wenhua & Liu Guobin Decadal sediment yield from an Alpine proglacial zone inferred from reservoir 161 sedimentation (Pasterze, Hohe Tauern, Austria) Martin Geilhausen, Jan-Christoph Otto, David Morche & Lothar Schrott Efficiency of rice straw mulch as a soil amendment to reduce splash erosion 173 Leila Gholami, Seyed Hamid Reza Sadeghi & Mahdi Homaee Thirty years of vegetation cover dynamics and planform changes in the Brenta River 178 (Italy): implications for channel recovery E. Rigon, J. Moretto, L. Mao, L. Picco, F. Delai, D. Ravazzolo, M. A. Lenzi & G. Kaless Numerical simulation of non-equilibrium sediment transport in a flume 187 Donatella Termini Soil erosion under different land uses in the riparian zone of the Three Gorges Reservoir, 198 China Yuhai Bao, Xiubin He, Jie Wei, Qiang Tang & Feng Guo Sedimentation patterns and sediment composition in a Norwegian glacial lake during a 202 large magnitude flood Patricia Kennie & Jim Bogen Impact of climate change on glacial sediment delivery to Norwegian rivers and 210 consequences for hydropower operations Jim Bogen, Truls Bønsnes & Galina Ragulina 4 Erosion and Sediment Yield Modelling

A GIS-based model for ditch erosion risk assessment in peatland forestry 221 Tapio Tuukkanen, Harri Koivusalo, Hannu Marttila, Antti Leinonen, Bjørn Kløve, Ari Laurén & Leena Finér Estimation of the spatial distribution of soil erosion in the hilly area of Sichuan, China 228 Xiaoli Jin, Genwei Cheng, C-Y Xu, Jihui Fan & Zelong Ma Model of water regulation in the Yangtze River Basin and its effects using remote 235 sensing techniques Xiankun Yang & X. X. Lu Characteristics of runoff processes on unmetalled loess roads under experimental rainfall 244 conditions Fengxia Tian, Xiubin He, Guiyu Li & Shiqing Zheng Mapping and spatial analysis of suspended sediment yields from the Russian Plain 251 Kirill Maltsev, Oleg Yermolaev & Vadim Mozzherin Estimating sediment trapping efficiency from Landsat images: a case study of the 259 Yellow River basin Lishan Ran & Xixi Lu Estimating the annual sediment yield of a small agricultural catchment in central Poland 267 Kazimierz Banasik, Dariusz Górski, Zbigniew Popek & Leszek Hejduk A Geomorphological Response Model for predicting sediment-related habitat change in 276 ephemeral rivers Bennie van der Waal & Kate Rowntree Estimation of sediment yield for geo-climatically diverse watersheds 284 Jui-Yi Ho, Chi-Cheng Yang, Kwan Tun Lee, Yu-Han Hsu, Shuyou Cao & Ravinder Kaur

5 Mountain Hazards and Debris Flow

Quantification and modelling of debris flows in the proglacial area of the 293 Gepatschferner, Austria, using ground-based LiDAR Florian Haas, Tobias Heckmann, Ludwig Hilger & Michael Becht A rare occurrence of landslides initiated by an extreme event in March 2007 in the 303 Alligator Rivers Region, Australia M. J. Saynor, W. D. Erskine, G. Staben & J. Lowry Study of viscous debris-flow surges moving on a residual layer in a flume 311 Mi Tian, Kai-Heng Hu, Chuan-Chang Wang, Chao Ma & Fa-Hong Lei

6 Monitoring and Tracing Methodology

Determining soil erosion by water using high resolution remotely-sensed data 319 Magdalena Fitrzyk Evaluation of two sediment tracers under simulated rainfall 327 Peter Strauss, Gema Guzman, Axel Mentler, Rosemarie Hösl, Shengping Wang, Jose Alfonso Gomez & Zhiqiang Zhang Cartographic-geoinformational estimation of spatio-temporal erosion dynamics of arable 332 soils in forest-steppe landscapes of the Russian Plain Oleg Yermolaev & Alina Avvakumova Using 137Cs measurements and sediment yield monitoring to document catchment-scale 338 sediment dynamics and budgets Jean P. G. Minella, Gustavo H. Merten, Desmond E. Walling & Michele Moro Hydrodynamic and sediment measurements in estuaries of Rio de Janeiro State, Brazil: 345 methodology and application Geraldo Wilson Junior MODIS-based remote sensing of suspended sediment concentrations of the Middle and 356 Lower Yangtze River, China Xi-Xi Lu, Jian-jun Wang & Cheng Liu Potential use of synthetic color-contrast aggregates and a digital image processing 364 technique in soil splash measurements Abdulvahed Khaledi Darvishan, Seyed Hamidreza Sadeghi, Mahdi Homaee & Mahmood Arabkhedri Understanding polycyclic aromatic hydrocarbon transfers at the catchment scale 369 combining chemical and fallout radionuclides analyses David Gateuille, Olivier Evrard, Irène Lefevre, Elodie Moreau-Guigon, Fabrice Alliot, Marc Chevreuil & Jean-Marie Mouchel

137 210 Use of Cs and Pbex peaks produced by events in the catchment for dating sediments 378 in the Jiulongdian Reservoir, Chuxiong, Yunnan Province, China Xinbao Zhang, Yi Long, Xiubin He, Anbang Wen & Dongchun Yan

137 210 Further investigation of the relationship between Cs and Pbex flux and sediment 385 output from two small experimental catchments in Calabria, southern Italy Paolo Porto, Desmond E. Walling, Giovanni Callegari & Carmelo La Spada Quantification of the sediment budget of a river basin, based on reconstruction of the 394 post-fallout redistribution of Chernobyl particle-bound 137Cs Vladimir Belyaev, Eugenia Shamshurina, Maxim Markelov, Valentin Golosov, Nadezda Ivanova, Valeriy Bondarev, Tatiana Paramonova, Olivier Evrard, Catherine Ottlé, Irène Lefèvre & Philippe Bonté Sediment source tracing in the Thina catchment, Eastern Cape, South Africa 404 Kate Rowntree, Pearl Mzobe & Bennie van der Waal Tracing the dispersion of sediment contaminated with radionuclides in catchments 412 exposed to Chernobyl and Fukushima fallout Olivier Evrard, Vladimir Belyaev, Caroline Chartin, Catherine Ottlé, Nadezda Ivanova, Maxim Markelov, Irène Lefèvre, Valentin Golosov & Philippe Bonté Assessing morphological changes in gravel-bed rivers using LiDAR data and colour 419 bathymetry J. Moretto, E. Rigon, L. Mao, F. Delai, L. Picco & M. A. Lenzi Using a Terrestrial Laser Scanner to assess the morphological dynamics of a 428 gravel-bed river L. Picco, L. Mao, M. Cavalli, E. Buzzi, E. Rigon, J. Moretto, F. Delai, D. Ravazzolo & M. A. Lenzi Investigating an Alpine proglacial sediment budget using field measurements, airborne 438 and terrestrial LiDAR data Tobias Heckmann, Florian Haas, David Morche, Karl-Heinz Schmidt, Joachim Rohn, Michael Moser, Matthias Leopold, Michael Kuhn, Christian Briese, Norbert Pfeifer & Michael Becht

Abstracts

The role of dams in the global sediment budget

DES E. WALLING Geography, College of Life and Environmental Sciences, University of Exeter, Exeter EX4 4RJ, UK [email protected]

Abstract Dams and their associated reservoirs are a key element of water resource development in most areas of the world and dams have been constructed on many of the world’s large rivers. The presence of dams causes sedimentation in the upstream reservoir and such sediment trapping can exert an important influence in reducing downstream sediment transport. Many of the world’s rivers now provide evidence of declining sediment loads as a result of dam construction, and it is clear that dams currently exert an important influence on land-ocean sediment transfer and the global sediment budget. There is, however, currently considerable uncertainty regarding the precise impact of dams and reservoirs on the global sediment budget. Two different approaches can be used to quantify this impact. The first focuses on the reduction of the annual global land- ocean sediment flux and the second on quantifying the total amount of sediment being sequestered behind dams. Current estimates of the reduction in the annual land-ocean sediment flux range from 2 to 5 Gt year-1. However, existing estimates of the total amount of sediment being sequestered behind the world’s dams are about an order of magnitude greater and in the range 25 to 60 Gt year-1. The apparent discrepancy between the results provided by the two different approaches requires further investigation. Key words dams; sediment trapping; suspended sediment loads; global sediment budget; reservoir sedimentation

Redistribution of sediment and sediment-associated contaminants in the River Chern basin during the last 50 years

VALENTIN GOLOSOV1,2, ELENA ASEEVA1, VLADIMIR BELYAEV1, MAXIM MARKELOV1 & ALISA ALYABIEVA1 1 Faculty of Geography, Lomonosov Moscow State University, GSP-1, 119991, Leninskie Gory, 1, Moscow, Russia 2 Institute of Ecology and Geography, Kazan Federal University, 420008, Kremlevskaya st., 18, Kazan, Russia [email protected] Abstract A detailed study was undertaken in the upper part of the River Chern basin (126 km2). An integrated approach was used to investigate the redistribution of sediment and sediment- associated contaminants within the upper part of the basin, upstream from the reservoir located in the middle reach of the main valley. It was found that maximum sheet, rill and gully erosion rates were observed during the 1960s. This led to increased erosion rates in all parts of the fluvial system. The intensity of erosion decreased considerably after 1991 for a number of reasons. The commencement of mining activity and the sharp increase in the application of chemical fertilizers caused detectable heavy metal pollution within the basin during the late 1950s and early 1960s, when the Mikhailovsky iron ore mining development started. As a result, concentrations of Zn and As in floodplain sediment increased and exceeded the maximum permissible levels, according to Russian human health standards. Key words erosion, sedimentation; 137Cs; heavy metal pollution; mining; sediment redistribution; Central European Russia

Delineation of China’s reservoirs and lakes using remote sensing techniques

XIXI LU, XIANKUN YANG & LISHAN RAN Department of Geography, National University of Singapore, Singapore, 118670 [email protected] Abstract We used remote sensing images to provide the first complete picture of the reservoirs and lakes located within China. We extracted 89 691 reservoirs, covering about 26 755 km2 of the land surface. By applying an empirical formula relating reservoir storage capacity and surface area, we estimated the total storage capacity to be about 770 km3. Also, we delineated more than 180 000 lakes and ponds, with a total surface area of about 79 767 km 2. These include 2721 lakes larger than 1 km2. Through comparison with previous studies, we found that dramatic changes have occurred over the past decades. Reservoir construction and water diversion have changed the spatial distribution and seasonal variation of water resources and have made the river systems fragmented. Additionally, this study found that more than 200 lakes of >1 km 2 on the Mongolia- Xinjiang Plateau and the Eastern Plain have disappeared, but about 50 lakes >1 km 2 have appeared on the Tibetan Plateau. The disappearing lakes on the Mongolia-Xinjiang Plateau and the newly appearing lakes on the Tibetan Plateau could be a result of climate change; whereas the disappearance of lakes on the Eastern Plain, especially in the middle–lower reaches of the Yangtze and Huaihe River basin, reflect the impact of human activities, such as land reclamation and urbanization. The database of delineated reservoirs will be employed to estimate the total amount of sediment trapped behind dams. Key words lakes; reservoirs; satellite images; remote sensing; hydropower; China

Erosion and Sediment Yields in the Changing Environment (Proceedings of a symposium held at the Institute of Mountain Hazards and Environment, CAS-Chengdu, China, 11–15 October 2012) (IAHS Publ. 356, 2012), 29- 36. Impacts of eco-restoration on suspended sediment load in the upper Yangtze River of China

HE XIUBIN1 & WEI JIE2 1 Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu, 610041, China [email protected] 2 Geography & Tourism College, Chongqing Normal University, Chongqing, 400047, China [email protected]

Abstract Vegetation coverage is of great importance to the ecosystem and plays a key role for soil conservation, runoff and sediment yields. Long-term gauging data indicate that eco-programs in the upper Yangtze basin launched since 1989 have increased vegetation coverage through massive afforestation and soil-water conservation measures. The accumulated planting area of 5.3 million hectares has increased catchment forest coverage from 11% in 1978, to 34% in 2010. The mean annual sediment load of 2.78 × 108 t since 1989 is evidently less than that of 5.23 × 108 t before 1989 (a 47% reduction). Comparing the vegetation coverage situation and the sediment regime during 1999–2002 to those of 1984–1998, shows that the riverine suspended sediment load decreased 1.10% per 1% increase in forest coverage. Since 2003, the sediment load has sharply declined due to rapid construction of reservoirs in the upper reaches. Key words afforestation; ecological programmes; sediment load; soil erosion; the upper Yangtze River

Annual fluxes of sediment-associated trace/major elements, carbon, nutrients and sulfur from US coastal rivers

ARTHUR J. HOROWITZ1, VERLON C. STEPHENS2, KENT A. ELRICK1 & JAMES J. SMITH1 1 US Geological Survey, Peachtree Business Center, 3039 Amwiler Road, Atlanta, Georgia 30360, USA [email protected] 2 US Geological Survey, Denver Federal Center, Building 53, MS 415, Lakewood, Colorado 80225, USA

Abstract About 260–270 Mt of suspended sediment are discharged annually from the conterminous USA; approximately 69% derives from Gulf rivers (n = 36), 24% from Pacific rivers (n = 42), and 7% from Atlantic rivers (n = 54). Elevated sediment-associated chemical concentrations relative to baseline levels occur in the reverse order of sediment discharges: Atlantic rivers (49%) > Pacific rivers (40%) > Gulf rivers (23%). Elevated trace element concentrations (e.g. Cu, Zn) tend to occur in association with present/former industrial areas and/or urban centres, particularly along the northeast Atlantic coast. Elevated nutrient concentrations occur along both the Atlantic and Gulf coasts, but are dominated by rivers in the urban northeast and by southeastern and Gulf coast “blackwater” streams. Elevated Ca, Mg, K and Na levels appear to reflect local petrology whereas elevated Ti, S, Fe, and Al concentrations are ubiquitous, possibly because they have both natural and anthropogenic sources. Almost all the elevated sediment-associated chemical concentrations/fluxes are lower than worldwide averages. Key words fluvial sediment-associated constituents; annual fluxes; conterminous USA Erosion and Sediment Yields in the Changing Environment (Proceedings of a symposium held at the Institute of Mountain Hazards and Environment, CAS-Chengdu, China, 11–15 October 2012) (IAHS Publ. 356, 2012). 49- 56

Transport of suspended sediment by the Vistula River basin upstream of Kraków, southern Poland, and the human impact during the second half of the 20th century

ADAM ŁAJCZAK Jan Kochanowski University, Institute of Geography, ul. Świętokrzyska 15, 25-406 Kielce, Poland [email protected]

Abstract The upper part of the Vistula River basin, upstream of the city of Kraków (7524 km2), southern Poland, represents an area where human activity has had a major impact on the rate and long-term trend of suspended sediment transport by rivers. During the 1950s and 1960s, the studied stretch of the Vistula River received increasing volumes of wastewater from industrialised and urbanised areas, primarily via its tributary the River Przemsza, which runs through the Upper Silesian Industrial Basin. These inputs subsequently reduced. At the same time, the transport of suspended sediment by other tributaries was declining due to reforestation and construction of new dams. Below the confluence of its three largest tributaries, the main river becomes overloaded with suspended sediment, largely of anthropogenic origin, and this rapidly accumulates within the embanked zone, especially along the two reaches where the river level is raised by several metres, due to impoundment. Key words suspended sediment; sediment loads; human impact; Upper Vistula River basin; southern Poland

Dynamics of bank erosion on the River Dane, England

JANET HOOKE School of Environmental Sciences, University of Liverpool, Liverpool L69 7ZT, UK [email protected]

Abstract Evidence for the temporal and spatial variability in bank erosion rates is provided from air photo evidence for three periods and annual ground mapping evidence since 1981. Data on rate and distances of bank erosion are analysed in relation to parameters of peak discharge. Based on the period 1984–1996, a scaling relationship and calibration equation for calculating mean amount of erosion in each year is produced and tested against actual amounts in the period 1997– 2001 and 2001–2007. The variability of the bank erosion has important implications for sediment supply and downstream impacts. Key words river channel; bank erosion rate; flood impacts; river meanders; channel morphology; sediment; England Erosion and Sediment Yields in the Changing Environment (Proceedings of a symposium held at the Institute of Mountain Hazards and Environment, CAS-Chengdu, China, 11–15 October 2012) (IAHS Publ. 356, 2012), 65- 71.

An update of the magnitude–frequency analysis of Rio Cordon (Italy) bedload data after 25 years of monitoring

L. PICCO1, L. MAO2, E. RIGON1, J. MORETTO1, D. RAVAZZOLO1, F. DELAI1 & M. A. LENZI1 1 Department of Land & Agroforest Environment, University of Padova, Agripolis-35020 Legnaro (PD), Italy 2 Departamento de Ecosistemas y Medio Ambiente, Pontificia Universidad Catolica de Santiago, Chile [email protected]

Abstract Quantification of bedload transport in high-gradient mountain streams is important, but field data necessary to test transport models are scarce. In the present work, we describe the experimental station for monitoring water and sediment fluxes built in 1985 on the Rio Cordon (Eastern Italian Alps), a small step-pool channel. The measuring station consists of an inclined frame that separates (at 20 mm truncation) fine and coarse sediments, which are continuously measured for accumulations by two turbidimeters. The 25-year dataset acquired, which comprises high-magnitude/low-recurrence flood events, has allowed a magnitude–frequency analysis of bedload volumes. Results from a combined frequency analysis of peak water discharge and total bedload volumes based on the 25 events are presented, focusing on discrepancies between recurrence intervals of peak discharge and bedload volume for each event. In addition, the integration between the sediment transport dataset and the repeated surveys of sediment sources and of channel changes has permitted to assess the geomorphic effectiveness of different flood events. The Rio Cordon measuring facilities have provided excellent data and valuable insights into the bedload dynamics of steep streams throughout its 25 years of operation, thanks to the close collaboration between the ARPAV-Veneto Region and the Department Land and Agro-forest Environments (University of Padova). However, the maintenance costs of the station are not trivial and may impact its future “vitality”. At the same time, improvement of the present instrumentation and installation of novel technology would make the station an ideal location for calibrating surrogate techniques for sediment transport monitoring. Key words bedload; steep channels; sediment supply; frequency analysis; step pool; alpine torrents

Sediment transport in the proglacial Fagge River (Kaunertal/Austria)

DAVID MORCHE1, FLORIAN HAAS2, HENNING BAEWERT1, TOBIAS HECKMANN2, KARL-HEINZ SCHMIDT1 & MICHAEL BECHT2 1 Institute for Geosciences and Geography, Martin-Luther-University Halle-Wittenberg, D-06099 Halle/Saale, Germany [email protected] 2 Catholic University of Eichstaett-Ingolstadt, Department of Physical Geography, Ostenstr.18, D-85072 Eichstaett, Germany Abstract The fluvial system in proglacial areas is more-or-less continuously fed with sediment by glacial melt water and infrequently supplied with sediment by landslides, debris flows, rock fall or fluvial transport from the coupled slopes. A part of the sediment input is temporarily stored in intermittent sinks (river bed, bars, braid plains). These stores can be reworked and then become sources for fluvial sediment transport during floods. Sediment transporting processes are highly variable in both the temporal and spatial scale. In consequence of this high variability, field-data based detailed knowledge of sediment fluxes and the interrelated geomorphological processes in proglacial areas is lacking. The present work is part of the research project “High-resolution Measurements of Morphodynamics in Rapidly Changing Proglacial Systems of the Alps”, that is set up in the Kaunertal, Austrian Alps. The project is focused on the quantification of fluvial sediment transport. Suspended sediment load and bed load are measured at different locations in the proglacial Fagge River. Surface changes of sediment sources are quantified by a comparison of multi-temporal terrestrial and airborne laser scanning data. Key words proglacial; sediment transport; bed load; terrestrial laser scanning; Kaunertal, Austria

Sediment and water quality in the Kam Tin River, Hong Kong

M. R. PEART1, L. FOK2 & J. CHEN3 1 Department of Geography, University of Hong Kong, Hong Kong, China [email protected] 2 Department of Science and Environmental Studies, Hong Kong Institute of Education, Hong Kong, China 3Department of Civil Engineering; University of Hong Kong, Hong Kong, China

Abstract River water quality has reflected development pressures in Hong Kong. The Hong Kong Government has adopted a range of measures to improve water quality including the enactment of the Water Pollution Control Ordinance which specifies Water Quality Objectives (WQO) for rivers. One of the key WQO for the Kam Tin River, one of the largest rivers in Hong Kong, is an annual median suspended solids value of <20 mg/L. During the years of 2006 to 2011, regular weekly sampling at the Kam Tin monitoring station revealed dry season median values for suspended solids of 82.1, 84.4, 52.6, 74.3, 82.2 and 60.6 mg/L, respectively, well above the WQO limits. In the summer wet season the annual median values are 52.2, 43.4, 19.1, 21.6, 25.0 and 56.6 mg/L, respectively, which are much lower than those in the dry season and in general exceed the WQO limit. Monitoring at three additional stations indicates spatial variation in sediment concentrations in the basin. For 2006 to 2011 the median chlorophyll-a concentrations of 19.8 and 11.3 µg/L were observed at Kam Tin for dry and wet seasons, respectively. There is also a need to examine sediment quality in the basin as enrichment of Zn, Pb, Cu, Ni and As against the crustal average has been observed for storm period suspended sediment. Key words water quality objective; suspended sediment; chlorophyll-a; sediment quality

Erosion and Sediment Yields in the Changing Environment (Proceedings of a symposium held at the Institute of Mountain Hazards and Environment, CAS-Chengdu, China, 11–15 October 2012) (IAHS Publ. 356, 2012)., 91- 97 Dynamics of sediment delivery in drain flow on clay soils across England and Wales

YUSHENG ZHANG, ADRIAN L. COLLINS & JOHN R. WILLIAMS ADAS, Pendeford House, Wobaston Road, Wolverhampton WV9 5AP, UK [email protected]

Abstract A large area of agricultural land across England and Wales is on drained clay soils. Field drains have been shown to be an efficient pathway for the delivery of sediment and associated agricultural pollutants to watercourses. As part of a major monitoring programme on agricultural diffuse pollution, sediment samples were collected from hydrologically-isolated experimental plots at two sites in England from 2007 to 2009. Temporal variations in drain sediment loss for different land use and soil types were examined and relationships between drain flow and sediment concentration were also explored. The data analysis has shown that there are significant contrasts between the two soil types under investigation and that the observed sediment concentrations are often above the limits set for freshwater fish. Efforts are being made to characterize the observed patterns with respect to soil and climate conditions to assist extrapolation to national scale for policy support purposes. Key words sediment loss; field drains; clay soils; plot experiments

Suspended sediment transport by rivers in the different climatic zones of Cameroon (Central Africa)

GASTON LIENOU1, GIL MAHE2, LUC SIGHA-MKAMDJOU3, JEAN EMMANUEL PATUREL4, JACOB NWALAL3 & JUSTIN NLOZOA3 1 The University of de Yaounde I, BP 812 Yaounde, Cameroon [email protected] 2 IRD, University Mohamed V Agdal, BP 8967, 10 000 Rabat Agdal, Morocco 3 IRGM, Yaounde Cameroon, 4 IRD, UMR HydroSciences Montpellier, BP 64 501, F-34394 Montpellier Cedex 5, France

Abstract Some watersheds representing the major climatic zones of Cameroon, in Central Africa, have been simultaneously investigated during the period 2002–2004. The patterns of monthly suspended sediment transport show a common form. In areas with a tropical climate, there is a hysteretic loop, with the maximum concentration preceding the flow peak. In these areas, the values of suspended sediment concentrations (up to 3000 mg L-1) and specific sediment yields (>200 t km-2 year-1) are high. In contrast, in areas with an equatorial climate, the monthly concentrations increase regularly with the monthly flow and sediment concentrations are about 15 mg L1 and specific sediment yields less than 10 t km-2 year-1. A comparison of recent results and historical data shows that in areas of dry tropical climate (Mayo Tsanaga) where flow rates have decreased by 50% since the late 1960s, average sediment concentrations increased from an overall average of 1050 to 2500 mg L-1, with a maximum exceeding 3000 mg L-1 in 2003. Conversely, in the equatorial zone (Ntem), the available data indicate no major change in sediment concentrations despite a decrease in flow rate of 19%. Key words Cameroon; climate; drought; suspended sediment transport Erosion and Sediment Yields in the Changing Environment (Proceedings of a symposium held at the Institute of Mountain Hazards and Environment, CAS-Chengdu, China, 11–15 October 2012) (IAHS Publ. 356, 2012)., 104-113

Are riverine sediment discharges sufficient to offset the sinking coast of Louisiana?

Y. JUN XU & TIMOTHY ROSEN School of Renewable Natural Resources, Louisiana State University Agricultural Center, Baton Rouge, Louisiana 70803, USA [email protected]

Abstract The Mississippi River and four other major rivers along Louisiana’s coast (USA) discharge a combined total of 620 km3 of water annually into the Gulf of Mexico. In addition to the vast quantity of freshwater, these river systems carry substantial sediments that affect physical, biological and human domains in the northern Gulf of Mexico. In the past century, river engineering and land use practices in the river basins have changed dramatically. A large number of locks and dams were built along the major tributary rivers including the Upper Mississippi River, Illinois River, Missouri River, Ohio River, Tennessee River, Arkansas River, and Red River, which has greatly contributed to the reduction in sediment yield to the continental shelf of the northern Gulf of Mexico. Concurrently, Louisiana’s coast has experienced the highest rate of relative sea-level rise of any region in the USA. In the past 50 years land loss rates along Louisiana’s coast have exceeded over 60 km2 year-1, and in the 1990s the rate has been estimated to be between 40 and 56 km2 year-1. This change represents 80% of the coastal wetland loss annually in the entire continental USA. The highest relative sea-level rise is 17.7 mm year -1 at Calumet, Louisiana, compared to 6.3 mm year-1 at Galveston, Texas, 1.5 mm year-1 at Biloxi, Mississippi, and 2.3 mm year-1 at Pensacola, Florida. Riverine sediments are precious resources to coastal Louisiana, and their effective management is of long-term strategic importance. This paper reports combined sediment yields from two major distributaries of the Mississippi River and four major coastal rivers in Louisiana for the most recent three decades, and discusses the actual availability of sediment and a new diversion approach – controlled overbank flow – that mimics the natural process of sediment replenishment over large areas. Key words riverine sediment; TSS yield; Mississippi-Atchafalaya River; coastal Louisiana, USA

Sediment quality in the water-level-fluctuation-zone of the Three Gorges Reservoir, China

ZHIJING CAO1 & YUHAI BAO2 1 College of Architecture and Environment, Sichuan University, no. 24 South Section 1, Yihuan Road, Chengdu, China [email protected] 2 Key Laboratory of Mountain Surface Processes and Ecological Regulation, Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, no. 9 Block 4 , South Renmin Road, Chengdu, China Abstract The water-level-fluctuation-zone (WLFZ) of the Three Gorges Reservoir (TGR) acts as an important area for sediment and associated contaminants deposition and remobilization. Knowledge of sediment quality in the WLFZ of the TGR plays an important role in evaluating geochemical baselines and understanding human influences on sediment geochemistry. When the water level of the TGR was low in summer 2010, sediment samples in the WLFZ were collected for the determination of heavy metals (Pb, Cr, Cu, Zn, Cd), and nutrients (TP, OM). Generally, concentrations of TP and heavy metals, except for Zn, in most of the sediment samples exceeded the Lowest Effect Levels, and the maximum concentrations of these elements were below the Severe Effect Levels. The results indicated the sediments were contaminated by Cu, Cd, Pb, Cr and phosphorus to some extent. In the sediment profiles, higher concentrations of Pb, Cr, Cu, Cd and TP were associated with subsurface sediment rather than surface material. In contrast to the nutrients, the generally higher concentration of heavy metals, except for Zn, in the bulk sediments appeared in the lowland at lower elevations rather than the higher elevation sloping land. Many of the spatial trends for heavy metals and nutrients were explained by the element properties, particle-size-selective deposition and post-depositional remobilization. As sensitive indicators of contaminants in aquatic systems, the heavy metals and nutrients in the sediments in the WLFZ reflect human activities in the TGR region and have implications for environmental management. Key words Three Gorges Reservoir; water-level-fluctuation-zone; heavy metals; nutrients; sediment; pollution extent

Assessing “modern background sediment delivery to rivers” across England and Wales and its use for catchment management

ADRIAN L. COLLINS1,3, IAN FOSTER2,6, YUSHENG ZHANG1, RICHARD GOODAY1, DAVID LEE1, DAVID SEAR3, PAMELA NADEN4 & IWAN JONES5 1 ADAS, Pendeford House, Wobaston Road, Wolverhampton WV9 5 AP, UK [email protected] 2 University of Northampton, School of Science and Technology, St George’s Avenue, Northampton NN2 6JD, UK 3 University of Southampton, Geography and Environment, Highfield, Southampton SO17 1BJ, UK 4 Centre for Ecology and Hydrology, Crowmarsh Gifford, Wallingford OX10 8BB, UK 5 Queen Mary University of London, School of Biological and Chemical Sciences, Mile End Road, London E1 4NS, UK 6 Department of Geography, Rhodes University, Grahamstown 6140, Eastern Cape, South Africa Abstract Catchment sediment management across England and Wales continues to require alternative criteria to the existing guideline standard (an annual mean suspended sediment concentration of 25 mg L-1) provided by the European Union Freshwater Fish Directive. In response, a recent collaborative science project has investigated the scope for developing alternative catchment-specific sediment targets using an integrated modelling toolkit coupling sediment pressures from agriculture and impacts on aquatic biota, including fish and macroinvertebrates. Part of this work involved using palaeolimnological reconstruction to quantify “modern background sediment delivery to rivers” (MBSDR) across England and Wales, prior to recent agricultural intensification. It is proposed that the estimates of MBSDR can be used to assess the maximum ceiling of mitigation because no management strategy should aim to control background sediment loss arising from natural physiographic and hydrological drivers, and to correct the gap between past, present or future projected sediment pressures on watercourses and “good ecological status” for sediment. Keywords sediment delivery; palaeolimnology; modelling; management; policy

Transient storage and release of sediment and phosphorus in a small urban impoundment

N. McLELLAN1, L. GRAY1, D. ALLIN2, K. DAMUDE2, A. DIFEBO2, K. McLEAN2, E. SARARAS2, M. STONE2 & J. PRICE2 1 Department of Civil and Environmental Engineering, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada 2 Department of Geography and Environmental Management, University of Waterloo, Ontario N2L 3G1, Canada [email protected]

Abstract A mass balance approach was used to quantify concentrations and loads of suspended solids and phosphorus (P) at the inflow and outflow of Laurel Pond, a small river impoundment in an urbanized watershed in Waterloo, Ontario, Canada, over a range of hydrological conditions. During baseflow and higher magnitude flow conditions, Laurel Pond was a sink for both sediment and P. However, 8.4 t of sediment and 8.6 kg of P were released from Laurel Pond during drawdown. Concentrations of sediment and P were positively correlated but inversely related to pond depth. A threshold water level was observed in the pond, below which the majority of sediment and P were released. During the Laurel Pond drawdown, 94% of suspended solids and 100% of TP measurements at the pond outflow exceeded Ontario Provincial Water Quality Objectives of 25 mg L-1 and 30 µg L-1, respectively. Key words urban impoundments; sediment; phosphorus; drawdown

Landslide impacts on suspended sediment sources following an extreme event in the Magela Creek catchment, northern Australia

WAYNE D. ERSKINE1,2 & MICHAEL J. SAYNOR1 1 Physico-Chemical Processes Group, Environmental Research Institute of the Supervising Scientist, GPO 461, Darwin NT 0801, Australia [email protected] 2 School of Environmental & Life Sciences, The University of Newcastle, PO Box 127, Ourimbah NSW 2258, Australia

Abstract Record rainfall of up to 784 mm occurred between 17:00 h 27 February and 17:00 h 2 March 2007 in the Magela Creek catchment, northern Australia. Maximum return periods for 48 and 72 h durations exceeded 1:1000 years. The 24-hour maximum (398.4 mm) is the largest recorded in the region and the 2007 storm exceeded all previous 48 and 72 h recorded rainfall in the Northern Territory but was only one-third of Probable Maximum Precipitation. Sixteen landslides (0.3 km2) were triggered over a small area where sandstone had been stripped to reveal dolerite. The Munsell® soil colour of the <63 µm fraction of suspended sediment showed that in 2008 a series of “red” flood pulses on Magela Creek at stations up- and downstream of Ranger mine were sourced from the landslides by localised storms. Active fluvial sediment sources were restricted to a very small area for short periods of time during specific hydrological events. Key words sediment colour; suspended sediment sources; sediment fingerprinting; “red” flood pulses

Driving forces in a floodplain restoration project: interaction between surface water, groundwater and morphodynamic processes during an ecological flooding

PETER FISCHER1, FLORIAN HAAS1,2 & BERND CYFFKA1,2 1 Catholic University of Eichstaett-Ingolstadt, Applied Physical Geography; 85072 Eichstaett, Germany [email protected] 2 Floodplain Institute Neuburg, Germany

Abstract Erosion, transport and deposition of sediment play a major role in restoration projects and sustainable river management. The main driving variables, water and sediment dynamics resurrect the natural processes in “riverscapes” and floodplains. After the first flooding of a new river course in the floodplain along the River Danube between Neuburg and Ingolstadt (Germany) in 2010 (up to 5 m3/sec), new morphological activity started instantly. However, intensive erosion rates were measured during the first two controlled ecological flood events with water discharges of 10 m3 s-1 and 20 m3 s-1. The relatively new river banks are prone to lateral erosion and during bankfull stages new undercut slopes have developed. To understand the processes in this new river channel, its development is being recorded by a package of methods such as terrestrial laser scanning (TLS) measurements. Key words river restoration; floodplain; ground-based LiDAR; hydromorphology; monitoring

Fractal geometry of aggregates in natural grassland soils with different restoration stages

ZHOU PING1, WEN ANBANG1, ZHUANG WENHUA2,3 & LIU GUOBIN3 1 Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, The key Laboratory of Mountain Surface Processes and Ecological Regulation, Chengdu, Sichuan 610041, China [email protected] 2 College of Water Conservancy and Hydropower, Sichuan University, Chengdu 610065, China 3 State Key Laboratory of Soil Erosion and Dryland Farming on Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling, Shaanxi 712100, China

Abstract Severe soil erosion occurs over 70% of the Loess Plateau in China. In this study, the fractal geometry of micro-aggregates were determined to compare fractal dimensions of the soils and physical and chemical characteristics of the soils in different restoration stages on the Loess Plateau. The results show that the fractal dimension of upper layer soil micro-aggregates decrease with increased restoration time. The fractal dimension (D) of soils at 0–20 cm changed from 2.360 ± 0.008 to 2.494 ± 0.015 with different restoration stage, while D changed from 2.441 ± 0.009 to 2.488 ± 0.016 at 20–40 cm and from 2.478 ± 0.028 to 2.492 ± 0.027 at 40–60 cm. D was significantly different (p < 0.01) for particles <0.001 at 0–20 cm. D increased with increasing sand content but decreased with increasing clay content. D was positively correlated with bulk density, non-capillary porosity, porosity ratio, total phosphorus, available potassium and ammonia nitrogen, but negatively correlated with capillary porosity, soil organic matter and total nitrogen. Keywords erosion environment; soil micro-aggregates; fractal dimension; different restoration stage

Decadal sediment yield from an Alpine proglacial zone inferred from reservoir sedimentation (Pasterze, Hohe Tauern, Austria)

MARTIN GEILHAUSEN1, JAN-CHRISTOPH OTTO1, DAVID MORCHE2 & LOTHAR SCHROTT1 1 Department of Geography and Geology, University of Salzburg, Hellbrunnerstrasse 34, A-5020 Salzburg, Austria [email protected] 2 University of Halle-Wittenberg, Institute of Geosciences and Geography; Von-Seckendorff-Platz 4, D-06120 Halle, Germany

Abstract Reservoir sedimentation over more than five decades enabled the quantification of subrecent sediment yield from the glacierized Pasterze catchment, a 40-km2 basin located in the Hohe Tauern Mountain range in Austria. Sediment yield is highly variable over an order of magnitude (1.5 to 16.7 × 104 t/year) with an average of ~ 6.3 ± 0.5 × 104 t/year resulting in a total sediment export of approx. 340 × 104 t of mainly fine grained sediment (D50 Ø coarse silt). This is equal to specific sediment yields (SSY) ranging from 0.4 to 4.2 × 103 t/km2/year (Ø 1.6 ± 0.1 × 10³ t/km²/year) at a total of 85.6 × 10³ t/km² in the 54 years studied. No significant correlation is found between annual data sets of sediment yield, discharge, glacial retreat and hydro-climate. Based on multi-temporal geomorphological mapping, a sandur (former proglacial lake) and a braid plain are identified as key landforms within the proglacial zone modulating sediment yield. It is assumed that sediment yield from proglacial zones will increase due to climate change which accelerates glacier melt. This study shows the impact of proglacial lakes on sediment yield which can reduce the connectivity between glacial sediment production and downstream sediment fluxes. The number of proglacial lakes within the Alps is expected to rise following accelerated glacial retreat. Three basins are located under the present tongue of Pasterze Glacier and further lakes will develop. It is assumed that sediment delivery from the Pasterze catchment will most likely be significantly altered in the near future. This will lead to changes in sediment yields with impacts on hydrology, river ecology and reservoir management. Key words sediment yield; proglacial lake; glacier forefield; reservoir sedimentation; Pasterze Glacier

Efficiency of rice straw mulch as a soil amendment to reduce splash erosion

LEILA GHOLAMI1, SEYED HAMID REZA SADEGHI2 & MAHDI HOMAEE3 1 Department of Watershed Management Engineering, Faculty of Natural Resources, Tarbiat Modares University, Member of Young Researchers Club, Noor Unit, PO Box 46417-76489, Noor, Iran [email protected] 2 Department of Watershed Management Engineering, Faculty of Natural Resources, Tarbiat Modares University, Noor, Iran 3 Department of Soil Science, Faculty of Agriculture, Tarbiat Modares University, Tehran, Iran

Abstract Splash erosion is caused by the impact of raindrops on the soil surface. Raindrops detach soil particles, alter soil structure and increase soil erosion. Therefore, strategies are required to control the runoff and soil erosion through the control of splash erosion. The most effective measures for reducing soil splash are the use of amendments to improve and reinforce soil aggregates and/or to deploy physical barriers to minimize raindrop impacts. Straw mulch is a natural amendment that reinforces soil aggregates and reduces soil erosion. The present study examines the efficiency of straw mulch to reduce splash erosion and was conducted using silt- loam soils collected from summer rangeland in the Alborz Mountains, northern Iran. Rainfall simulators were used in the laboratory on 6 m2 plots to test the utility of soil amendments to reduce erosion. Data from nine splash cups placed on three replicates for each treatment (treated vs bare soil) showed that the straw mulch reduced splash erosion in all directions. Key words Alborz Mountains, Iran; erosion control; mulch; natural amendment; splash erosion

Thirty years of vegetation cover dynamics and planform changes in the Brenta River (Italy): implications for channel recovery

E. RIGON1, J. MORETTO1, L. MAO2, L. PICCO1, F. DELAI1, D. RAVAZZOLO1, M. A. LENZI1 & G. KALESS2 1 Department of Land & Agroforest Environment; University of Padova, Agripolis-35020 Legnaro (PD), Italy [email protected] 2 Departamento de Ecosistemas y Medio Ambiente, Pontificia Universidad Catolica de Chile, Santiago, Chile

Abstract The timing and extent of the morphological changes that occurred in the last 30 years in a gravel-bed river (the Brenta River, eastern Italian Alps) have been analysed using eight sets of aerial photos, repeated topographic measurements and morphological–vegetational surveys. Human activities have produced modifications in the natural sediment regime and the cessation of gravel extraction in the late 1990s seems to have caused vegetation erosion and channel widening. Alteration of sediment regime has played a major role in the medium and short-term channel evolution. However, only relevant flood events (RI > 10 years) appear to determine substantial islands erosion. The analysis at smaller scale (sub-reach level) proved to be more effective in describing morphological responses and its relationships with the sediment dynamics within the study reach (20 km). The understanding of sediment transfer at the sub-reach level will provide helpful guidelines for the discussion of channel recovery potential. Key words channel changes; fluvial erosion; vegetation cover dynamic; river restoration

Numerical simulation of non-equilibrium sediment transport in a flume

DONATELLA TERMINI Dipartimento di Ingegneria Civile, Ambientale e Aerospaziale, Viale delle Scienze, 90128 Palermo, Italy [email protected] ; [email protected]

Abstract Simulations of non-uniform bed load sediment transport processes under non- equilibrium conditions require characterization of alluvial system processes to immediately overcome variations of sediment boundary conditions. Due to the introduction of man-made sediment barriers, the amount of sediment load entering in the downstream river reach is different from that going out and river reaches adjust to a new equilibrium condition. In supply limited rivers, bed degradation can occur, while in transport limited rivers bed aggradation can occur. When alluvial streams are unable to adjust to variation of sediment boundary conditions, spatial lags or adaptation lengths are required to reach the equilibrium transport capacity. Accordingly, quantitative estimates of sediment transport in river-control engineering and water management projects are essential to evaluate the changes in riverbeds. This study focuses on erosion processes caused by decreasing sediment load imposed at the upstream boundary of a straight flume and a 1-D numerical approach is used to simulate the process. Key words rivers; erosion; sediment transport; hydraulic structure; numerical simulation

Soil erosion under different land uses in the riparian zone of the Three Gorges Reservoir, China

YUHAI BAO1, XIUBIN HE1, JIE WEI2, QIANG TANG1,3 & FENG GUO1,3 1 Key Laboratory of Mountain Environment Evolution and Regulation, Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, China [email protected] 2 Geography and Tourism College, Chongqing Normal University, Chongqing 400047, China 3 Graduate University of Chinese Academy of Sciences, Beijing 100049, China

Abstract Different land use and management practices have varying impacts on soil erosion. There are few reports concerning the land-use effects on soil erosion for the riparian zone of the Three Gorges Reservoir (TGR). The present study investigated soil erosion rates in artificial grassland, natural grassland, cropland, and bare land at the riparian zone in the middle reach of the TGR during 2008–2012. Fifteen experimental plots with different land use were set up to observe soil erosion rates with erosion pins. The results show that the maximum soil erosion rate was 94 887 t km-2 year-1 in the conventional tillage farmland, followed by 92 423 t km-2 year-1 in the bare land, 64 670 t km-2 year-1 in the bunch planting farmland, 37 794 t km-2 year-1 in the natural grassland, and the minimum soil erosion rate was 21 340 t km-2 year-1 in the artificial grassland. Key words Three Gorges Reservoir; riparian zone; land uses; soil erosion

Sedimentation patterns and sediment composition in a Norwegian glacial lake during a large magnitude flood

PATRICIA KENNIE & JIM BOGEN Norwegian Water Resources and Energy Directorate, PO Box 5091 Maj., 0301 Oslo, Norway [email protected]

Abstract In 1979 a large magnitude flood on the southeast side of the Jostedalsbreen ice-cap in western Norway created distinct sediment layers in glacial Lake Nigardsvatn. This paper examines sediment transport and deposition in a glacial meltwater river in 1979, 1993 and 2002, and the downstream variation in thickness of sediment deposits in Lake Nigardsvatn. The thickest deposit was observed next to the delta front and a more rapid downstream decrease occurred during the 1979 event. Particle-size analysis indicated that the 1979 and 2002 sediment layers contained more coarse fractions (>31 µm) than the 1993 layer. During 1979, coarser sediment was deposited closest to the delta compared to the 1993 and 2002 events. The occurrence of rainfall induced floods during the summer of 2011 led to the highest water discharge and suspended sediment load on record. The observed conditions were comparable to that of higher magnitude floods. Key words sedimentation; glacial lake; suspended sediment loads; varve thickness; large magnitude flood; grain size distribution

Erosion and Sediment Yields in the Changing Environment (Proceedings of a symposium held at the Institute of Mountain Hazards and Environment, CAS-Chengdu, China, 11–15 October 2012) (IAHS Publ. 356, 2012),210- 218. Impact of climate change on glacial sediment delivery to Norwegian rivers and consequences for hydropower operations

JIM BOGEN, TRULS BØNSNES & GALINA RAGULINA Norwegian Water Resources and Energy Directorate, PO Box 5091 Maj., 0301 Oslo, Norway [email protected]

Abstract The possible effects of climate change on sediment delivery from glaciers and the consequences for hydropower operations are discussed in this paper. Present climate change scenarios predict a rise in summer temperature of 2.5–4.0°C in Norway towards 2100, an increase in precipitation of 5–20% in the southwestern part of the country, and a general increase in the frequency of extreme rainfall events. Most of the glaciers will melt and sediment transport is likely to increase as a result of the melting. During the last decade, high summer temperatures and high precipitation have caused the highest volume of runoff and sediment load in the meltwater river flowing from the Nigardsbreen Glacier, since measurements began in 1968. A study of the subglacial morphology obtained from low frequency radio-echo soundings revealed that a number of depressions beneath the glaciers will form lakes when the glaciers disappear and act as sedimentation basins in the future rivers. The increased sediment delivery from the glaciers will thus not always increase the sediment input to downstream reaches. Changes in sediment delivery to hydropower stations will depend on the local conditions and the operation rules. Key words bed load; climate change; glacial erosion rate; hydropower planning; sediment yield; suspended load; ungauged glacierised basins

A GIS-based model for ditch erosion risk assessment in peatland forestry

1 2 1 TAPIO TUUKKANEN , HARRI KOIVUSALO , HANNU MARTTILA , ANTTI LEINONEN3, BJØRN KLØVE1, ARI LAURÉN4 & LEENA FINÉR4 1 University of Oulu, Water Resources and Environmental Engineering Laboratory, PO Box 4300, FI-90014 University of Oulu, Finland [email protected] 2 Aalto University School of Engineering, Department of Civil and Environmental Engineering, PO Box 15200, FI-00076 Aalto, Finland 3 Finnish Regional Forestry Centre, Pieksämäki, Tallikatu 3-5, FI-76100 Pieksämäki, Finland 4 Finnish Forest Research Institute, Joensuu Research Unit, PO Box 68, FI-80101 Joensuu, Finland

Abstract The maintenance of ditch networks in conjunction with peatland forestry increases erosion and suspended solid loads delivered to watercourses. Against this background, we tested a simple one-dimensional GIS-based steady-state hydraulic model for assessing erosion risk in forest ditch networks. Model accuracy and reliability were tested against experimental field measurements in two intensively drained peatland forestry catchments located in northern and central Finland. Despite the crude assumptions behind the simplified computational method, we found that low input data requirements, good visualization capabilities and short run times make the model a promising tool for informing water protection planning, although the spatial location of erosion risk simulated with the simplified model was not always consistent with the observed pattern of ditch erosion. Key words peatland drainage; erosion risk; modelling; GIS; water protection

Estimation of the spatial distribution of soil erosion in the hilly area of Sichuan, China

XIAOLI JIN1,2, GENWEI CHENG1, C-Y XU3, JIHUI FAN1 & ZELONG MA2 1 Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu, Sichuan 610041, China 2 Sichuan Hydraulic Science Research Institute, Chengdu 610072, China 3 Department of Geosciences, University of Oslo, Norway

Abstract The hilly area of Sichuan (China) has suffered from soil erosion as a result of the intensive agriculture and steep topography. Many different methods have been used for the estimation of soil erosion and no clear consensus about erosion rates and subsequent sediment delivery ratios (SDR) has been reached. In this study, the Universal Soil Loss Equation (USLE) with different parameter estimation methods was applied to two river basins (i.e. Weichenghe (WCH) and Lizixi (LZX)) with the help of GIS techniques. The results were compared with those of previous studies based on remote sensing, erosion plots or the 137Cs technique. The main results can be summarized as: (1) different rainfall erosivity estimation methods generate vastly different results; (2) using two-dimensional slope length produces higher soil erosion rate estimates and lower SDRs than the conventional approach in USLE; (3) the average annual soil erosion rates for WCH and LZX were estimated at 706 t km-2 year-1 and 3040 t km-2 year-1, respectively, and the corresponding sediment delivery ratios at 0.27 and 0.38; and (4) the high erosion rates reflect the high altitude and intensive agricultural land use. Key words USLE; rainfall erosivity; soil erosion rate; spatial distribution

Model of water regulation in the Yangtze River Basin and its effects using remote sensing techniques

XIANKUN YANG & X. X. LU Department of Geography, National University of Singapore, 118670 Singapore [email protected]

Abstract Based on remotely sensed images, about 42 000 dams, with a total storage capacity of about 270 km3, have been constructed in the Yangtze River Basin. This large volume of water amounts to nearly one-third of the total annual discharge of the Yangtze River. Reservoir construction has dramatically changed the spatial distribution of water resources in the basin. Substantial amounts of water are now impounded in the upper reaches of the basin for energy generation and the pattern of seasonal water discharge has been altered. Future anthropogenic changes could further worsen the situation as additional large hydropower projects are completed in the upper reaches of the basin. This will cause more serious ecosystem disconnectivity through the elimination of free-flowing streams. Free-flowing streams are vanishing on the mainstem and major tributaries, such as the Jinshajiang, Wujiang, Dadu, Yuanjiang and Jialingjiang, because of reservoir construction. At present, 4688 km of streams are regulated by dams and this figure could increase to 7298 km by 2025 when all the dams currently under construction are put into operation. If all the planned dams are completed, the figure could jump to 10 675 km, or about 43% of the total length of the streams. At that time, almost all the mainstem and major tributaries will be fully regulated and this could lead to very serious negative ecosystem effects by disconnecting sediment/nutrient transport and fish migration. Keywords water regulation; reservoirs; free flowing; the Yangtze River basin; hydropower

Characteristics of runoff processes on unmetalled loess roads under experimental rainfall conditions

FENGXIA TIAN1, XIUBIN HE1, GUIYU LI2 & SHIQING ZHENG3 1 Key Laboratory of Mountain Surface Processes and Ecological Regulation, Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, China [email protected] 2 CHINA Water Resources Pearl River Planning, Surveying and Designing Co. Ltd, Guangzhou 510610, China 3 Institute of Soil and Water Conservation, CAS & MWR, Yangling, Shaanxi 712100, China

Abstract Runoff commonly triggers severe erosion on unmetalled road surfaces and roadside slopes. In this context, this paper explores the use of theoretical analysis of runoff processes for an unmetalled loess road, based on the kinematic wave theory, and explores the key controlling factors. The results of the theoretical analysis are assessed using measured data from simulated rainfall tests on artificial experimental road sections. The results suggested that: (1) the kinematic wave equation is appropriate for describing dynamic processes of overland flow on unmetalled loess roads; (2) the discharge, depth and velocity of runoff on the unmetalled loess roads increased with increasing rainfall intensity, whereas the velocity of runoff increased with increasing slope length; (3) the velocity of runoff increased as flow depth decreased with increasing slope gradient; and (4) unit width discharge on road sections with different slopes under the same rainfall intensity (120 mm h-1) remained similar. Keywords unmetalled loess roads; kinematic wave theory; flow depth; flow velocity; slope gradient

Erosion and Sediment Yields in the Changing Environment (Proceedings of a symposium held at the Institute of Mountain Hazards and Environment, CAS-Chengdu, China, 11–15 October 2012) (IAHS Publ. 356, 2012), 251-258. Mapping and spatial analysis of suspended sediment yields from the Russian Plain

KIRILL MALTSEV, OLEG YERMOLAEV & VADIM MOZZHERIN Department of Landscape Ecology, Institute of Geography and Ecology of Kazan Federal University, 18 Kremlyovskaya, 420008 Kazan, Russia [email protected]

Abstract The aim of this paper is to demonstrate the potential use of a GIS and associated database to map and analyse global patterns of sediment yield. Attention focuses on the suspended sediment yield (SSY) data available for the European territories of the Russian Federation and the variation of SSY across part of the Russian Plain. A GIS and database have been developed for the Volga River basin. The GIS system permits the drainage basins for which SSY data are available to be delineated and the database conflates information on sediment yield and the hydrological and physiographic characteristics of the individual drainage basins. A map of the variation of annual sediment yield within the Volga basin is presented. Key words erosion; suspended sediments yield; GIS; thematic maps; hydrological stations

Estimating sediment trapping efficiency from Landsat images: a case study of the Yellow River basin

LISHAN RAN & XIXI LU Department of Geography, National University of Singapore, 117570 Singapore [email protected]

Abstract This paper is concerned with the man-made reservoirs constructed in the Yellow River basin. Given the shortcomings of conventional approaches to assessing reservoirs constructed in large river basins, remote sensing techniques offer several benefits. Remote sensing data can provide high-resolution synoptic and repetitive information at short time intervals. Based on the results of reservoir delineation and storage capacity estimation, in this study the Yellow River basin was divided into 12 sub-basins for which the water residence time and potential sediment trapping efficiency were explored. Water cycling in the basin has been greatly regulated and its residence time increased to 3.97 years during 2006–2009. The basin-wide sediment trapping efficiency is 95.2%, indicating that most sediment entering the channels would be trapped by the reservoirs. With more reservoirs to be completed, it is expected that flow regulation will become much more important and that the sediment flux reaching the ocean will further decrease. Key words water residence time; sediment trapping efficiency; Landsat; Yellow River basin

Estimating the annual sediment yield of a small agricultural catchment in central Poland

KAZIMIERZ BANASIK, DARIUSZ GÓRSKI, ZBIGNIEW POPEK & LESZEK HEJDUK Warsaw University of Life Sciences – SGGW, Department of Water Engineering, 166 Nowoursynowska str., PL-02-787 Warsaw, Poland [email protected]

Abstract The annual sediment yield of a small (91 km2) agricultural catchment in central Poland has been estimated, based on river flow measurements and catchment characteristics, and verified by reservoir surveys. Although soil erosion rates and sediment yields in this part of Poland are generally seen as low by global standards, reservoir sedimentation is a problem and there is a need to develop and validate a method for estimating catchment sediment yields. In this investigation, the suspended sediment input to a reservoir, has been estimated using the Universal Soil Loss Equation coupled with a sediment delivery ratio (USLE-SDR). The annual bed load has been estimated based on the flow duration curve and three different bed load formulae. The reservoir surveys were carried out four times between 1980 and 2009. Between 1980 and 2009 the reservoir lost approx. 13% of its capacity. A close agreement was found between the amount of sediment deposited in the reservoir and the sediment input estimated using the USLE-SDR and the bed-load formulae. Key words sediment yield; sediment delivery; sediment budget; reservoir sedimentation; USLE; bed load formulae; Poland

A Geomorphological Response Model for predicting sediment-related habitat change in ephemeral rivers

BENNIE VAN DER WAAL & KATE ROWNTREE Geography Department, Rhodes University, Grahamstown, South Africa [email protected]

Abstract Protection of aquatic ecosystems is a legal requirement emanating from the water laws of many countries globally. Methods to assess environmental flows are being developed and applied throughout the world, with an emphasis on perennial rivers. In South Africa, scientists are addressing environmental flow needs for ephemeral rivers by developing a Geomorphological Response Model that integrates expert knowledge into a decision support system, based on mathematically defined response curves. Geomorphologists play a key role in predicting the long- term change in ecosystem structure following water-related developments. In this paper we explain the process whereby we are developing geomorphic response curves that can be used to predict habitat related channel change in rivers for which there are limited hydrological or geomorphological data. Key words Environmental flows; non-perennial rivers; sediment processes; habitat change; ecosystem structure; decision support system Erosion and Sediment Yields in the Changing Environment (Proceedings of a symposium held at the Institute of Mountain Hazards and Environment, CAS-Chengdu, China, 11–15 October 2012) (IAHS Publ. 356, 2012, 284- 289).

Estimation of sediment yield for geo-climatically diverse watersheds

JUI-YI HO1, CHI-CHENG YANG2, KWAN TUN LEE1, YU-HAN HSU1, SHUYOU CAO3 & RAVINDER KAUR4 1 Department of River & Harbor Engineering, National Taiwan Ocean University, Keelung, Taiwan 202, R.O.C. [email protected] 2 Water Resource Agency, No. 76, Sec.3 An-He Rd., Taipei, Taiwan 10651, Taiwan 202, R.O.C. 3 State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610065, Sichuan, China 4 Water Technology Center of Indian Agricultural Research Institute, New Delhi 110012, India

Abstract Because the route of eroded sediment is complicated, estimating watershed erosion during storms is difficult. The objective of this study is to develop a sediment transport model which can be used to simulate sedimentgraphs in geo-climatically diverse watersheds. A physically-based soil erosion simulation model was developed for sediment yield estimation. The studied watersheds are the Goodwin Creek watershed in USA and the Hsia-Yun watershed in Taiwan. The good agreement between the simulated and recorded sedimentgraphs has shown the capability of the developed erosion model for sediment yield simulation in the Goodwin Creek watershed, USA. However, because the erosion model did not consider sediment inflow due to landslides, the sediment quantity was underestimated during the peak-flow period in the Hsia- Yun watershed, Taiwan, when severe landslides occurred in the simulated typhoon events. Key words sediment transport model; soil erosion; landslide

Quantification and modelling of debris flows in the proglacial area of the Gepatschferner, Austria, using ground-based LiDAR

FLORIAN HAAS, TOBIAS HECKMANN, LUDWIG HILGER & MICHAEL BECHT Catholic University of Eichstaett-Ingolstadt; Ostenstr. 18, 85072 Eichstaett, Austria [email protected] Abstract In August 2011, a large rainstorm event triggered several slope type debris flows on the steep Little Ice Age moraine deposits of the Gepatschferner. Since high resolution ground-based LiDAR data are available for before and after the event, erosion and accumulation of the single debris flows could be quantified very accurately. Besides the quantification of the sediment yield of this event, the DEM of difference calculated from the two LiDAR epochs allows for the identification and detailed mapping of process areas of the debris flows. Using the ground-based LiDAR DEM and the mapped starting zones of the event, the process areas of the debris flows were modelled using a 2-D friction model. The model was calibrated and validated by the detailed maps of the process areas. The paper presents the first results of both the quantification and the modelling of the slope type debris flows caused by the 2011 rainstorm event. Key words debris flows; proglacial area; ground-based LiDAR; modelling; PROSA

A rare occurrence of landslides initiated by an extreme event in March 2007 in the Alligator Rivers Region, Australia

M. J. SAYNOR1, WAYNE D. ERSKINE1,2, G. STABEN3 & J. LOWRY1 1 Physico-Chemical Processes Group, Environmental Research Institute of the Supervising Scientist, GPO 461, Darwin NT 0801, Australia [email protected] 2 School of Environmental & Life Sciences, The University of Newcastle, PO Box 127, Ourimbah NSW 2258, Australia 3 Department of Natural Resources, Environment, the Arts and Sport, Northern Territory Government, Darwin, NT, Australia

Abstract The wettest water year on record at Jabiru Airport (2600 mm) in northern Australia occurred in 2006/07. A total of 1940 mm of rain fell in February and March 2007, with 737 mm occurring over 72 h between 28 February and 2 March. This rainfall and the associated flood event had return periods of at least 1:100 years on the annual maximum series. At least 49 landslides occurred on well vegetated, exhumed olivine dolerite surfaces surrounded by quartzose sandstone in the East Alligator River drainage basin. The number, extent, morphometry and soil properties of the landslides were determined using remote sensing imagery, combined with field and laboratory measurements. No evidence of previous mass movements on dolerite was found. The frequency of these mass movements is certainly much rarer than 1:100 years. Mass movements have not previously been considered a significant sediment source in this area because of their truly rare occurrence. Key words mudslides; debris slides; landslide frequency; olivine dolerite; clay soils; extreme events

Study of viscous debris-flow surges moving on a residual layer in a flume

MI TIAN1,2,3, KAI-HENG HU1,2, CHUAN-CHANG WANG1,2,3, CHAO MA 1,2,3 & FA- HONG LEI1,2,3 1 Key Laboratory of Mountain Hazards and Earth Surface Processes, CAS, Chengdu, Sichuan 610041, China 2 Institute of Mountain Hazards and Environment, CAS, Chengdu, Sichuan 610041, China 3 Graduate school of Chinese Academy of Science, Beijing 100041, China [email protected] Abstract Debris flows are observed as a series of surges in nature and are characterized as rolling waves. A residual layer plays a vital role during the movement of surges. This paper examines debris flow surges in a flume to study the mass exchange between the surge front and the residual layer. Initial findings show that the surge head incorporates materials from the residual layer in a rolling way. The ratio of mass exchange increases linearly with mean flow velocity and mass exchange has an impact on the resistance coefficient. Key words debris-flow surge; head of surge; residual layer; mass exchange; flume

Determining soil erosion by water using high resolution remotely-sensed data

MAGDALENA FITRZYK Institute of Geodesy and Geoinformatics, Wroclaw University of Environmental and Life Sciences, Grunwaldzka 53, 50-357 Wroclaw, Poland [email protected] Abstract The Trzebnickie Hills located to the north of Wroclaw, Poland, are dominated by fertile loess soil formations which are highly susceptible to water erosion. Against this context, the aim of this study was to investigate the advantages and limitations of using satellite imagery in the assessment of water erosion of loess soils. More specifically, the work focused on the interferometric analysis of high resolution SAR images from the TerraSAR-X satellite using coherence imagery. The results of this analysis were superimposed on a digital elevation model and slopes map to assess the relationship with coherence loss. Both visual interpretation and statistical analysis demonstrated that there may be correlation between local terrain slope angles and decreased correlation in coherence maps. Since slope is a major trigger of soil denudation, it was concluded that coherence maps can serve as a useful tool for extracting and delineating eroded areas. However, certain conditions must be met before the assessment of erosion from coherence maps can be considered credible and these are briefly discussed. Key words loess soils erosion; TerraSAR-X; interferometry

Evaluation of two sediment tracers under simulated rainfall

PETER STRAUSS1, GEMA GUZMAN2, AXEL MENTLER3, ROSEMARIE HÖSL1, SHENGPING WANG4, JOSE ALFONSO GOMEZ 2 & ZHIQIANG ZHANG5 1 Federal Agency for Water Management, A-3252 Petzenkirchen, Austria [email protected] 2 Institute for Sustainable Agriculture-CSIC, 14080 Cordoba, Spain 3 University for Natural Resources and Life Sciences, 1190 Vienna, Austria 4 North China Electricity Power University, Beijing 102206, P. R. China 5 Beijing Forestry University, Beijing 100083, P. R. China

Abstract A number of different tracing approaches have already been established, including the use of rare earth oxides or environmental radionuclides. However, since existing techniques face various limitations, the search for alternative procedures continues. Two alternative tracing approaches involve the use of organophilic clays and magnetic iron oxides. This study performed a combined test of these tracers to assess potential contrasts in their behaviour under a controlled rainfall simulation experiment. The experiment consisted of a simulated rainfall event of 55 mm.h-1 applied to a bed–shoulder system (2 × 1.14 m). The results highlighted differences between the tracers in terms of their enrichment in sediment and different soil aggregate classes. Comparison of the contribution of the different plot sections to the total sediment export using both tracers suggested that most of the sediment originated from the shoulders. Key words erosion; tracer; magnetic iron oxide; rainfall simulation; organophilic clays

Cartographic-geoinformational estimation of spatio-temporal erosion dynamics of arable soils in forest-steppe landscapes of the Russian Plain

OLEG YERMOLAEV & ALINA AVVAKUMOVA Department of Landscape Ecology, Institute of Ecology and Geography of Kazan Federal University, 18 Kremlyovskaya, 420008 Kazan, Russia [email protected] Abstract The intensity of soil erosion in the forest-steppe landscapes of the Russian Plain was assessed using a cartographic method and GIS. The aim of the research was to devise a method for analysing the spatio-temporal dynamics of soil erosion intensity under conditions of high agricultural production. The intensity of anthropogenic erosion was assessed for the period from 1970 to 2007. These years cover the period of highest intensity of agricultural land use (USSR) and the subsequent period of agricultural loading reduction experienced during the transitional economy of Russia during the 1990s. Spatio-temporal analysis of soil erosion was conducted by the creation of vector thematic erosion maps, generated using the “overlay” cartographic approach. The change in soil erosion contours was estimated for each key soil type. Key words soil erosion; GIS; thematic maps; dynamics; river basins

Using 137Cs measurements and sediment yield monitoring to document catchment-scale sediment dynamics and budgets JEAN P. G. MINELLA1, GUSTAVO H. MERTEN2, DESMOND E. WALLING3 & MICHELE MORO2 1 Department of Soils, Federal University of Santa Maria; 97105-900, Santa Maria, Brazil [email protected] 2 Institute of Hydraulic Research, Federal University of Rio Grande do Sul; 91501-970 Porto Alegre, Brazil 3 Department of Geography, University of Exeter; Amory Building, Rennes Drive, Exeter EX4 4RJ, UK

Abstract The rapid expansion of agriculture in Brazil has increased erosion rates and sediment yields, causing many negative environmental and economic impacts. Given the need to reduce the negative impacts, there is an important need for studies that assess the response of catchment sediment dynamics and budgets to soil and water conservation practices. 137Cs measurements have been combined with measurements of sediment yield, to study the sediment dynamics and budget of a small (1.19 km 2) rural catchment in southern Brazil. 137Cs measurements have been used to estimate medium-term erosion and deposition rates along 17 transects in tobacco growing areas. These data have been used to estimate sediment mobilization rates from the cultivated areas subject to significant erosion. By combining the information on sediment mobilization and deposition rates provided by the 137Cs measurements with available measurements of sediment yield, a sediment budget for the catchment has been established. Key words soil erosion, sediment yield, tobacco cultivation, Brazil, catchment management, caesium-137

Hydrodynamic and sediment measurements in estuaries of Rio de Janeiro State, Brazil: methodology and application

GERALDO WILSON JUNIOR PENO-COPPE – Rio de Janeiro Federal University – UFRJ; Technology Center, Bloc C, 209, Rio de Janeiro 21945-970, Brazil [email protected]; [email protected]

Abstract Accurate cross-sectional field data on water currents and sediment concentrations, among other variables, are required to understand and describe hydrodynamic, sedimentologic and morphologic processes in estuarine environments. Hence, cross-sectional field measurements have to be simultaneously and continuously obtained, by a well equipped team, during at least one tidal cycle. Unfortunately, Brazilian hydrometric teams are neither well equipped nor numerous. To address this problem, a new method was developed and applied in Estuaries of Rio de Janeiro State: (a) in the Iguaçu River estuarine stretch, by a team equipped only with one current meter and conventional sediment samplers, and (b) in the São Francisco Channel Estuary, where traditional and modern equipment, such as an Acoustic Doppler Current Profiler – ADCP was used. This method is also applicable for measuring hydrodynamic and sediment phenomena in non-permanent open channels during high-flow events (e.g. during floods). Key words sediment and morphological processes; fluvial and estuarine morphology; hydrodynamic and sediment measurements; Brazilian estuaries; sediment movements

Erosion and Sediment Yields in the Changing Environment (Proceedings of a symposium held at the Institute of Mountain Hazards and Environment, CAS-Chengdu, China, 11–15 October 2012) (IAHS Publ. 356, 2012)., 356-363 MODIS-based remote sensing of suspended sediment concentrations of the Middle and Lower Yangtze River, China

XI-XI LU1, JIAN-JUN WANG2 & CHENG LIU3 1 Department of Geography, National University of Singapore; 10 Kent Ridge Crescent, 119260, Singapore 2 Department of Geodesy and Geomatics Engineering, University of New Brunswick; 15 Dineen Drive, PO Box 4400, Fredericton, New Brunswick E3B 5A3, Canada [email protected] 3 International Research and Training Center on Erosion and Sedimentation (IRTCES); IRTCES, PO Box 366, No. 20 Chegongzhuang Road West, Beijing, 100048, China

Abstract Suspended sediment concentration (SSC) is a critical parameter in the study of river sediment transport and water quality variations. The potential for estimating SSC in large rivers using satellite images has been examined in previous studies. Using the Middle and Lower Yangtze River as an example, this paper applies a simple segmented linear regression to eliminate the errors of SSC estimation caused by the nonlinear relation between spectral reflectance and the SSC of turbid rivers. In comparison to previous studies, this one improves the accuracy of estimated SSC values based on the high temporal resolution Terra Moderate Resolution Imaging Spectroradiometer (MODIS) images. The improvement was particularly significant for water samples with high SSC values. This is crucial for studying the spatial and temporal variations of SSC in large rivers that can result from climate change and human activities such as dam construction and illegal sand extractions. Key words satellite remote sensing; suspended sediment concentration (SSC); Terra MODIS images; turbid water; Yangtze River

Potential use of synthetic color-contrast aggregates and a digital image processing technique in soil splash measurements

ABDULVAHED KHALEDI DARVISHAN1, SEYED HAMIDREZA SADEGHI1, MAHDI HOMAEE2 & MAHMOOD ARABKHEDRI3 1 Department of Watershed Management Engineering, Faculty of Natural Resources, Tarbiat Modares University, PO Box 46414-356, Noor, Iran [email protected] 2 Department of Soil Science, Faculty of Agriculture, Tarbiat Modares University, PO Box 14115-336, Tehran, Iran 3 Soil Conservation and Watershed Management Research Institute, PO Box 13445-1136, Tehran, Iran

Abstract A digital computer-based method for measuring soil splash was evaluated in the present study. Accordingly, Synthetic Color-Contrast Aggregates (SCCA), having the same size, shape and specific gravity as those of natural soil aggregates were used as tracers for detecting particle movement. Subsequently, the amount and intensity of sheet erosion was inferred with the help of Digital Image Processing (DIP) techniques using MATLAB. The present study was conducted under laboratory conditions with a simulated rainfall intensity of some 90 mm h-1 and a slope of 30%, using sandy-loam soils taken from a summer rangeland in the Alborz Mountains, northern Iran. Soil erosion was mapped based on the DIP technique and finally compared with the density distribution of SCCA to evaluate the accuracy of the approach. The results show that the method can be used for measuring soil splashed downslope, and for estimating the amount and intensity of splash. Key words Alborz Mountains, Iran; digital image processing; erosion tracers; sheet erosion; soil splash; synthetic color-contrast aggregates

Understanding polycyclic aromatic hydrocarbon transfers at the catchment scale combining chemical and fallout radionuclides analyses

DAVID GATEUILLE1,2, OLIVIER EVRARD1, IRÈNE LEFEVRE1, ELODIE MOREAU-GUIGON2, FABRICE ALLIOT2, MARC CHEVREUIL2 & JEAN-MARIE MOUCHEL2 1 LSCE, CEA-CNRS-UVSQ/IPSL, Gif-sur-Yvette, France [email protected] 2 SISYPHE, UPMC-CNRS-EPHE, Paris, France

Abstract Contamination of river water and sediment constitutes a major environmental issue for industrialized countries. Polycyclic aromatic hydrocarbons (PAHs) are a group of persistent organic pollutants characterized by two or more fused rings. Some PAHs present a high risk for environmental and human health because of their carcinogenic and/or mutagenic properties. However, there remains a lack of understanding regarding the various processes responsible for PAH transfers from one environmental compartment to another. This study aims to quantify PAH transfers at the catchment scale. Chemical analyses and measurement of radionuclides have been carried out on soil and sediment samples collected in one upstream subcatchment of the Seine River basin during one year. Results show a large PAH accumulation in sediment and suspended matter and this highlights the importance of local sources for PAH distributions and concentrations at the subcatchment scale. Key words environmental contamination; polycyclic aromatic hydrocarbons (PAHs); catchment scale; pollutant transfers; fallout radionuclides

137 210 Use of Cs and Pbex peaks produced by events in the catchment for dating sediments in the Jiulongdian Reservoir, Chuxiong, Yunnan Province, China XINBAO ZHANG, YI LONG, XIUBIN HE, ANBANG WEN & DONGCHUN YAN Key Laboratory of Mountain Environmental Change and Regulation, Institute of Mountain Hazards and Environment, C.A.S., Chengdu, 610041, China [email protected]

Abstract A 393-cm long sediment core was collected from the Jiulongdian Reservoir in 2004. In addition to the expected 1963 137Cs peak at a depth of 231–237 cm, there was an unusual 137Cs 210 137 210 and Pbex peak at a depth of 15–21 cm. The Cs and Pbex peak is related to a forest fire 210 occurring in the spring of 1998 and can be used for sediment dating. The Pbex peak at a depth of 331–337 cm reflects the surface horizon of the original soil beneath the reservoir, which has been buried by the reservoir deposits since the reservoir was built in 1958. Based on the storage volume vs depth relationship for the reservoir, the amounts of sediment deposited during the periods 1959–1962, 1963–1997 and 1998–2003 were estimated to be 249.48 × 104 t, 262.78 × 104 t and 30.94 × 104 t, respectively. The corresponding specific sediment yields for the three periods are estimated to be 2421.2 t km-2 year-1, 291.5 t km-2 year-1 and 200.2 t km-2·year-1, respectively. The highest specific sediment yields were associated with deforestation during the “Great Leap Forward” of 1958–1959. However, the severe erosion resulting from deforestation rapidly declined when the natural vegetation re-established itself after deforestation ceased. 137 210 Key words Cs; Pbex; reservoir; sediment core; forest fire; deforestation; soil erosion

Further investigation of the relationship between 137Cs and 210 Pbex flux and sediment output from two small experimental catchments in Calabria, southern Italy

PAOLO PORTO1,2, DESMOND E. WALLING1, GIOVANNI CALLEGARI3 & CARMELO LA SPADA2 1 College of Life and Environmental Sciences, University of Exeter, Amory Building, Rennes Drive, Exeter,EX4 4RJ, UK [email protected]; [email protected] 2 Dipartimento STAFA, Università degli Studi Mediterranea, Località Feo di Vito, Reggio Calabria, Italy 3 CNR – Istituto per i Sistemi Agricoli e Forestali del Mediterraneo, Sezione Ecologia e Idrologia Forestale, Rende (CS), Italy Abstract Information on rates of soil loss and associated rates of soil redistribution are seen as an important requirement for effective environmental management. The use of the fallout 137 210 radionuclides caesium-137 ( Cs) and excess lead-210 ( Pbex) to document rates of soil and sediment redistribution in the landscape has attracted increasing attention in recent years. A 137 210 detailed investigation of sediment and sediment-associated Cs and Pbex fluxes has been initiated in two experimental catchments (approx. 1.5 ha in size) located in southern Italy. For both catchments, information on the sediment and radionuclide fluxes associated with 50 individual storm events has been assembled for the period 2005–2011. This measurement programme has identified a number of differences in the erosional response on the two 137 210 catchments and provides a useful demonstration of the further potential for using Cs and Pbex measurements to shed light on the internal functioning of a catchment, in terms of sediment mobilization and delivery. Key words caesium-137; lead-210; soil erosion; suspended sediment; sediment dynamics, sediment delivery, Italy Erosion and Sediment Yields in the Changing Environment (Proceedings of a symposium held at the Institute of Mountain Hazards and Environment, CAS-Chengdu, China, 11–15 October 2012) (IAHS Publ. 356, 2012), 394-403.

Quantification of the sediment budget of a river basin, based on reconstruction of the post-fallout redistribution of Chernobyl particle-bound 137Cs

VLADIMIR BELYAEV1, EUGENIA SHAMSHURINA1, MAXIM MARKELOV1, VALENTIN GOLOSOV1,2, NADEZDA IVANOVA1, VALERIY BONDAREV1, TATIANA PARAMONOVA3, OLIVIER EVRARD4, CATHERINE OTTLÉ4, IRÈNE LEFÈVRE4 & PHILIPPE BONTÉ4 1 Laboratory of Soil Erosion and Fluvial Processes, Lomonosov Moscow State University, GSP-1, 119991, Leninskie Gory, 1, Moscow, Russia [email protected] 2 Institute of Ecology and Geography, Kazan Federal University, Kremlevskaya st., 18, Kazan, Russia 3 Department of Radioecology and Ecotoxicology, Faculty of Soil Science, Lomonosov Moscow State University, Leninskie Gory, GSP-1, Moscow, 119991, Russia 4 Laboratoire des Sciences du Climat et de l’Environnement (LSCE/IPSL), Unité Mixte de Recherche 8212 (CEA/CNRS/UVSQ), Centre de Recherche du CNRS, Avenue de la Terrasse, 91 198 Gif-sur-Yvette Cedex, France Abstract Quantitative assessment of the sediment budget of a fluvial system is a key approach to understanding its geomorphic behaviour and an essential tool for investigating the redistribution of particle-bound contaminants along the sediment cascade. Here, we present a study involving the application of several independent approaches for quantifying the post-fallout (1986–2009) redistribution of Chernobyl particle-bound 137Cs and the basin-scale sediment budget for the River Plava basin situated in the northern part of the Srednerusskaya Upland (Central European Russia). The techniques employed include 137Cs-based sediment tracing, two soil erosion models and the analysis of soil profile morphology. The results show that most of the sediment originating from human-accelerated soil erosion on cultivated slopes is redeposited on the uncultivated lower parts of the slopes or in the bottoms of infilled gullies, hollows and 1–3rd order valleys. The River Plava valley itself represents a system dominated by efficient transport, with very limited floodplain sediment storage. The 137Cs-contaminated sediment export from the River Plava basin outlet exerts a significant impact on the River Upa. Its floodplain sediment contamination by 137Cs downstream of the River Plava mouth increases by almost an order of magnitude. Key words fluvial system; sediment budget; sediment sources and sinks; 137Cs; human-accelerated soil erosion; Central European Russia

Sediment source tracing in the Thina catchment, Eastern Cape, South Africa KATE ROWNTREE, PEARL MZOBE & BENNIE VAN DER WAAL Rhodes University, PO Box 94, Grahamstown, 6140, South Africa [email protected]

Abstract The Mount Fletcher Dam on the Thina River, South Africa, was completed in 2008; 33% of its storage capacity has since been lost to sediment deposition. Highly erodible soils developed from mudstones and shales that dominate the lower catchment lithology are a likely source of sediment. Soils developed from basalt located higher in the catchment are less erodible, but steep slopes increase the erosion potential. As these two soil types have distinctive magnetic signatures, the reservoir sediment should provide a record of its main source area. Magnetic signatures from a sediment core revealed a cyclical pattern of sedimentation, with alternating high and low values that may be linked to the passage of floods. These magnetic signatures do not match those of mudstone/shale-derived soils, and point to a significant but variable input of basaltic sediment. A number of hypotheses are proposed to explain this anomaly. Implications for catchment restoration are discussed. Key words land degradation; gully erosion; sediment tracing; magnetic signatures; watershed restoration

Tracing the dispersion of sediment contaminated with radionuclides in catchments exposed to Chernobyl and Fukushima fallout

OLIVIER EVRARD1, VLADIMIR BELYAEV2, CAROLINE CHARTIN1, CATHERINE OTTLÉ1, NADEZDA IVANOVA2, MAXIM MARKELOV2, IRÈNE LEFÈVRE1, VALENTIN GOLOSOV2 & PHILIPPE BONTÉ1 1 Laboratoire des Sciences du Climat et de l’Environnement (LSCE/IPSL; CEA-CNRS-UVSQ), Gif-sur-Yvette, France [email protected] 2 Laboratory of Soil Erosion and Fluvial Processes, Faculty of Geography, Moscow State University, Moscow, Russia Abstract The Chernobyl and Fukushima nuclear power plant accidents led to the release of large quantities of radionuclides into the environment. Several of those radionuclides (e.g. 134Cs and 137Cs) strongly sorb onto soil particles. Once delivered to rivers by erosion processes and runoff, sediment redistribution can lead to the progressive dispersion of radioactive contamination into larger areas over time. This paper deals with case studies conducted in Russia (the 2000 km2 River Plava catchment affected by Chernobyl fallout in 1986), and in Japan (the 5000 km 2 highly contaminated area of Fukushima Prefecture). A key prerequisite for undertaking studies of the subsequent redistribution of contaminated sediment in catchments and river systems is a good knowledge of the initial spatial pattern of soil contamination by fallout radionuclides. In this contribution, we check the local validity of the initial contamination map provided for the Russian case study site and outline the implications for conducting a similar study in Japan. Key words fallout radionuclides; sediment tracing; nuclear accident; redistribution of contaminated sediment; catchment; agriculture Erosion and Sediment Yields in the Changing Environment (Proceedings of a symposium held at the Institute of Mountain Hazards and Environment, CAS-Chengdu, China, 11–15 October 2012) (IAHS Publ. 356, 2012). 419-427.

Assessing morphological changes in gravel-bed rivers using LiDAR data and colour bathymetry

J. MORETTO1, E. RIGON1, L. MAO2, F. DELAI1, L. PICCO1 & M. A. LENZI1 1 Department of Land, Environment, Agriculture and Forestry, University of Padua – Agripolis 35020 Legnaro (PD), Italy [email protected] 2 Departamento de Ecosistemas y Medio Ambiente, Pontificia Universidad Catolica de Chile, Santiago, Chile

Abstract Estimating underwater features of channel bed surfaces without the use of bathymetric sensors results in very high levels of uncertainty. A novel approach to create more accurate and detailed Digital Terrain Models (DTMs) integrates LiDAR-derived elevations of dry surfaces, water depth of wetted areas derived from aerial photos and a predictive depth–colour relationship. This method was applied in three different sub-reaches of a northeastern Italian gravel-bed river (Brenta) before and after flood events occurred in November and December 2010 (recurrence interval: 8 and 10 years). From the data collected through channel field survey, a regression model which calculates channel depths using the correct intensity of three colour bands was implemented. LiDAR and depth points were merged and interpolated into a DTM which features an average error of ±18 cm. The morphological evolution and the sediment volume change calculated through a difference of DTMs shows deposition and erosion areas, indicating a deficit which reduces as it goes downstream. Key words fluvial erosion–deposition processes; gravel-bed river; colour bathymetry; LiDAR data; floods

Using a Terrestrial Laser Scanner to assess the morphological dynamics of a gravel-bed river

L. PICCO, L. MAO2, M. CAVALLI3, E. BUZZI1, E. RIGON1, J. MORETTO1, F. DELAI1, D. RAVAZZOLO1 & LENZI MA1 1 Department of Land, Environment, Agriculture and Forestry; University of Padova – Agripolis 35020 Legnaro (PD), Italy [email protected] 2 Department of Ecosystems and Environment, Pontificia Universidad Catolica de Chile; Santiago, Chile 3 CNR-IRPI, Corso Stati Uniti 4, 35127 Padova, Italy

Abstract Braided rivers are dynamic and complex environments shaped by the balance of the flow, sediment regimes and the influence of the riparian vegetation. The balance between sediment supply and transport capacity determines the morphological evolution of a river. The aim of the study is to analyse the short-term morphological dynamics and the processes of erosion and deposition along a sub-reach of a low impacted gravel-bed braided river (the Tagliamento River, Italy) using a Terrestrial Laser Scanner (TLS). The device used is a pulsed TLS able to collect up to 50 000 points per second at a spatial resolution up to one point per mm2. The study area is around 23 ha and has been surveyed before and after significant floods of recurrence interval approx. 15 years and 12 years. The differences of the two DEMs (DoD) computed revealed consistent episodes of erosion and deposition within the analysed area, showing a strong dynamic of the Tagliamento River. Key words difference of DEMs (DoD); Terrestrial Laser Scanner (TLS); fluvial systems; morphological changes; Tagliamento River, Italy

Investigating an Alpine proglacial sediment budget using field measurements, airborne and terrestrial LiDAR data

TOBIAS HECKMANN1, FLORIAN HAAS1, DAVID MORCHE2, KARL-HEINZ SCHMIDT2, JOACHIM ROHN3, MICHAEL MOSER3, MATTHIAS LEOPOLD4, MICHAEL KUHN5, CHRISTIAN BRIESE6, NORBERT PFEIFER6 & MICHAEL BECHT1 1 Dept of Physical Geography, Cath. University of Eichstaett-Ingolstadt, Ostenstraße 18, D-85072 Eichstaett, Germany [email protected] 2 Institute for Geosciences and Geography, University of Halle-Wittenberg, Germany 3 Dept of Applied Geology, University of Erlangen-Nuremberg, Germany 4 Dept of Geomorphology and Soil Science, Technical University of Munich, Weihenstephan, Germany 5 Institute of Meteorology and Geophysics, University of Innsbruck, Austria 6 Institute of Photogrammetry and Remote Sensing, Vienna University of Technology, Austria

Abstract The ongoing recession of Alpine glaciers since the end of the Little Ice Age (LIA) has exposed stores of glacial sediment to the activity of paraglacial processes. Slope wash, fluvial processes and mass movements (including debris flows, slides and falls) within the proglacial area (i.e. the area within the LIA terminal moraines) have received comparatively little attention in previous studies of the (pro)glacial sediment budget that have focused mainly on suspended and bedload sediment transport in proglacial streams. Additionally, there is a need for research concerning the relative importance of non-glacial and glacial contributions to the sediment budget and the downstream consequences of increased proglacial geomorphic activity. The PROSA joint project (High-resolution measurements of morphodynamics in rapidly changing PROglacial Systems of the Alps) is designed to tackle these problems through a quantification of the afore- mentioned hillslope and channel processes within the forefield of the Gepatsch Glacier (Central Alps, Austria) using high-resolution LiDAR data. On the local scale, field measurements and digital elevation models from multi-epoch terrestrial LiDAR data will be combined to map and quantify sediment (re-)mobilisation, erosion and deposition. The catchment-scale sediment budget will be established by multi-epoch high-resolution airborne LiDAR data, upscaling of local findings using geomorphological models including the appraisal of slope–channel coupling, and an assessment of fluvial sediment export beyond the outlet of the catchment (which consists of a reservoir). This paper summarises the processes effective in proglacial systems, works out research needs with respect to sediment budgets in changing proglacial areas, and outlines the research framework of the PROSA joint project. It complements two papers on preliminary results published in this volume. Key words proglacial sediment budget; airborne LiDAR; terrestrial LiDAR; Central Alps; Tyrol

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