The report herein consists of a two phase study of sedimentation in John H. Kerr Reservoir. First is a comparison of suspended sediment data, which was collected by a VPI&SU team, to theoretical sedimentation patterns. A fairly good agreement was found. The field monitoring trips were performed a total of ten times between March 30,1981 and March 3, 1982. The VPI&SUdata is presented in graphical form, in terms of the suspended sediment distribution in evidence each research trip, as well as the patterns that were evident at each station during the period of monitoring. The second phase compares historical sediment inflow data provided by the U.S.G.S. to three Kerr Reservoir sedimentation studies performed by the U.S. Army Corps of Engineers. The. period involved is from Jan. 1952-0ct.1976. The discrepancy involved is calculated, and possible causes are discussed. In the 24-year period analyzed, only 1.48 percent of the total storage volume of Kerr Reservoir was lost due to sediment accumulation, indicating that the long term operation of the reservoir is not significantly affected by sedimentation. / Master of Engineering

The Little North Santiam River Basin is a 111-square mile watershed located in the Cascade Range of western Oregon. The Little North Santiam River is a major tributary to the North Santiam River, which is the primary source of drinking water for Salem, Oregon and surrounding communities. Consequently, water quality conditions in the Little North Santiam River, such as high turbidity, affect treatment and delivery of the drinking water. Between 2001 and 2008, suspended-sediment loads from the Little North Santiam River accounted for 69% of the total suspended-sediment load that passed the treatment plant. Recent studies suggest that much of this sediment originates from landslide activity in the basin. Using airborne Light Detection and Ranging (LiDAR)-derived imagery, 401 landslides were mapped in the Little North Santiam River Basin. Landslide types vary by location, with deep-seated earth flows and earth slumps common in the lower half of the basin and channelized debris flows prominent in the upper basin. Over 37% of the lower basin shows evidence of landslide activity compared to just 4% of the upper basin. Instream turbidity monitoring and suspended-sediment load estimates during the winter of 2009-2010 demonstrate a similar distribution of sediment transport in the basin. During a 3-month study period, from December 2009 through February 2010, the lower basin supplied 2,990 tons, or 91% of the suspended-sediment load to the Little North Santiam River, whereas the upper basin supplied only 310 tons of sediment. One small 23-acre earth flow in the lower basin, the Evans Creek Landslide, supplied 28% of the total suspended-sediment load, even though it only comprises 0.0004% of the basin. The Evans Creek Landslide is an active earth flow that has been moving episodically since at least 1945, with surges occurring between 1945 and 1955, 1970 and 1977, in February 1996, and in January 2004. Recent erosion of the landslide toe by Evans Creek continues to destabilize the slope, supplying much of the sediment measured in the Little North Santiam River. Over the last 64 years, the average landslide movement rate has been between 5 and 12 feet per year.

Submitted in fulfilment of the requirements of the degree of Master of Engineering , Durban University of Technology, Durban, South Africa, 2016. / Reservoirs are designed to specific volume called the dead storage to be able to withstand the quantity of particles in the rivers flowing into it during its design period called its economic life. Therefore, accurate calculation of the quantities of sediment being transported is of great significance in environment engineering, hydroelectric equipment longevity, river aesthetics, pollution and channel navigability. In this study different input combination of monthly upstream suspended sediment concentration and upstream flow dataset for Inanda Dam for 15 years was used to develop a model for each month of the year. The predictive abilities of each of the developed model to predict the quantity of suspended sediment flowing into Inanda Dam were also compared with those of the corresponding developed Sediment Rating Curves using two evaluation criteria - Determination of Coefficient (R2) and Root-Mean-Square Error (RMSE). The results from this study show that a genetic programming approach can be used to accurately predict the relationship between the streamflow and the suspended sediment load flowing into Inanda Dam. The twelve developed monthly genetic programming (GP) models produced a significantly low difference when the observed suspended sediment load was compared with the predicted suspended sediment load. The average R2 values and RMS error for the twelve developed models were 0.9996 and 0.3566 respectively during the validation phase. The Genetic Programming models were also able to replicate extreme hydrological events like predicting low and high suspended sediment load flowing into the dam. Moreover, the study also produced accurate sediment rating curve models with low RMSE values of between 0.3971 and 11.8852 and high R2 values of between 0.9833 and 0.9962. This shows that sediment rating curves can be used to predict historical missing data of the quantity of suspended sediment flowing into Inanda Dam using existing streamflow datasets. The results from this study further show that the predictions from the Genetic Programming models are better than the predictions from the Sediment Raring Curve models, especially in predicting large quantities of suspended sediment load during high streamflow such as during flood events. This proves that Genetic Programming technique is a better predictive tool than Sediment Raring Curve technique. In conclusion, the results from this study are very promising and support the use of Genetic Programming in predicting the nonlinear and complex relationship between suspended sediment load and streamflow at the inlet of Inanda Dam in KwaZulu-Natal. This will help planners and managers of the dam to understand the system better in terms of its problems and to find alternative ways to address them.

[Truncated abstract] With rapidly increasing population densities along coastlines and rising global sea levels, coastal protection has become a major concern for coastal communities. Predicting sediment transport in nearshore regions, however, is one of the most challenging tasks faced by coastal researchers in designing coastal structures or beach nourishment schemes. Although nearshore sediment transport mainly occurs in the longshore direction, cross-shore sediment transport is crucial in determining the shoreline evolution and beach morphology . . . This study investigated the factors influencing sediment re-suspension and cross-shore suspended sediment flux in the frequency domain through a series of field measurements conducted at several different locations and a numerical model. Only oscillatory flow components were examined and the mean flow components were not considered. Although many different factors such as cross-shore location with respect to breaker line, significant wave height to water depth ratio (Hs/h), normalised horizontal velocity skewness (<u³>/‹u²›³/²), median grain size (d50), breaker type, and wave groupiness appeared to influence the magnitude of cross-shore suspended sediment flux, bed ripples was identified as the major contributing factor in changing the direction of suspended sediment flux due to incident swell waves. Moreover, the direction changed significantly with ripple type. High frequency measurements, obtained to examine the influence of turbulent kinetic energy (TKE) on higher sediment suspension events observed under wave groups indicated that higher TKE was generated at the seabed by approaching wave groups, which in turn resulted in higher suspension events.°1

by Wong On Nei. / Thesis submitted in: October 2004. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 101-116). / Abstracts in English and Chinese. / ABSTRACT --- p.ii / 摘要 --- p.iv / ACKNOWLEDGEMENTS --- p.vi / TABLE OF CONTENTS --- p.vii / LIST OF TABLES --- p.xi / LIST OF FIGURES --- p.xiii / Chapter CHAPTER ONE --- INTRODUCTION --- p.1 / Chapter 1.1 --- Background --- p.1 / Chapter 1.2 --- Lethal and sublethal effects of SS on fish --- p.2 / Chapter 1.2.1 --- Biological effects --- p.2 / Chapter 1.2.2 --- Molecular biomarkers --- p.3 / Chapter 1.2.2.1 --- Acetylcholinesterase activity inhibition assay --- p.4 / Chapter 1.2.2.2 --- Induction of cytochrome P450 mRNA --- p.5 / Chapter 1.2.2.3 --- Induction of metallothionein mRNA --- p.6 / Chapter 1.2.3 --- Study on CYP1A and MT expression / induction --- p.8 / Chapter 1.2.3.1 --- Reverse Transcription (RT) --- p.8 / Chapter 1.2.3.2 --- Polymerase chain reaction (PCR) --- p.8 / Chapter 1.3 --- Objectives --- p.11 / Chapter CHAPTER TWO --- MATERIALS AND METHODS --- p.13 / Chapter 2.1 --- Study sites --- p.13 / Chapter 2.2 --- Sediment --- p.15 / Chapter 2.2.1 --- Sediment samples collection --- p.15 / Chapter 2.2.2 --- Sediment handling --- p.15 / Chapter 2.2.3 --- Sediment dry-wet (w/w) ratio measurement --- p.15 / Chapter 2.2.4 --- Heavy metal content analysis --- p.16 / Chapter 2.2.5 --- Organic content analysis --- p.16 / Chapter 2.3 --- Test organism --- p.17 / Chapter 2.4 --- Bioassays --- p.17 / Chapter 2.4.1 --- 10-day exposure treatments --- p.17 / Chapter 2.4.1.1 --- Experimental setup --- p.17 / Chapter 2.4.1.2 --- Procedure --- p.21 / Chapter 2.4.1.3 --- Tissue sample collection --- p.22 / Chapter 2.4.2 --- 30-day exposure treatments --- p.22 / Chapter 2.4.2.1 --- Behavioural observations --- p.23 / Chapter 2.4.2.2 --- Tissue sample collection --- p.23 / Chapter 2.5 --- Molecular Biomarkers --- p.25 / Chapter 2.5.1 --- Tested samples --- p.25 / Chapter 2.5.2 --- Acetylcholinesterase activity inhibition assay --- p.25 / Chapter 2.5.2.1 --- Acetylcholinesterase activity assay --- p.25 / Chapter 2.5.2.2 --- BioRad Bradford assay --- p.26 / Chapter 2.5.2.3 --- Calculation of specific enzyme activity --- p.26 / Chapter 2.5.3 --- Study on CYP1A and MT expression / induction --- p.27 / Chapter 2.5.3.1 --- Gill and liver tissue samples --- p.27 / Chapter 2.5.3.2 --- Preparation of ribonuclease free reagents and apparatus --- p.27 / Chapter 2.5.3.3 --- Isolation of total RNA --- p.27 / Chapter 2.5.3.4 --- Spectrophotometric analyses of DNA and RNA --- p.28 / Chapter 2.5.3.5 --- First strand cDNA synthesis --- p.28 / Chapter 2.5.3.6 --- Cloning and sequencing of CYP1A and MT gene --- p.29 / Chapter 2.5.3.7 --- RT-PCR co-amplification of CYP1A and 18S rRNA --- p.34 / Chapter 2.5.3.8 --- Real-time RT-PCR --- p.36 / Chapter CHAPTER THREE --- RESULTS --- p.39 / Chapter 3.1 --- Sediment chemistry --- p.39 / Chapter 3.1.1 --- Sediment dry-wet (w/w) ratio --- p.39 / Chapter 3.1.2 --- Heavy metal content of sediments --- p.39 / Chapter 3.1.3 --- Levels of total PCBs and PAHs in sediment --- p.39 / Chapter 3.2 --- Monitoring of test conditions --- p.42 / Chapter 3.3 --- Bioassays --- p.42 / Chapter 3.3.1 --- Survivorship --- p.42 / Chapter 3.3.2 --- Growth --- p.46 / Chapter 3.3.3 --- Feeding rate --- p.51 / Chapter 3.3.4 --- Behaviour --- p.54 / Chapter 3.3.5 --- Sediment clogging --- p.59 / Chapter 3.3.6 --- Body lesions --- p.59 / Chapter 3.3.7 --- Abnormal behaviour --- p.59 / Chapter 3.4 --- Molecular biomarkers --- p.63 / Chapter 3.4.1 --- Acetylcholinesterase activity inhibition assay --- p.63 / Chapter 3.4.2 --- Cloning and sequencing of CYP1A and MT gene --- p.66 / Chapter 3.4.3 --- RT-PCR co-amplification of CYP1A and 18S rRNA --- p.73 / Chapter 3.4.4 --- Real-time RT-PCR --- p.77 / Chapter CHAPTER FOUR --- DISCUSSION --- p.84 / Chapter 4.1 --- Sediment chemistry --- p.84 / Chapter 4.2 --- Biological responses --- p.85 / Chapter 4.3 --- Molecular biomarkers --- p.91 / Chapter 4.3.1 --- Acetylcholinesterase activity inhibition assay --- p.91 / Chapter 4.3.2 --- Cloning and sequencing of CYP1A and MT gene --- p.93 / Chapter 4.3.3 --- RT-PCR co-amplification of CYP1A and 18S rRNA --- p.93 / Chapter 4.3.4 --- Real-time RT-PCR --- p.95 / Chapter 4.4 --- Recommendations --- p.99 / Chapter 4.5 --- Conclusions --- p.100 / REFERENCES --- p.101 / APPENDIX --- p.117

Pak Ah Pan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (leaves 149-158). / Abstracts in English and Chinese. / ABSTRACT --- p.ii / 摘要 --- p.vi / ACKNOWLEDGEMENTS --- p.vii / TABLE OF CONTENTS --- p.ix / LIST OF TABLES --- p.xiv / LIST OF FIGURES --- p.xvi / Chapter CHAPTER ONE --- LITERATURE REVIEWS --- p.1 / Chapter 1.1. --- Sediment pollution problems --- p.1 / Chapter 1.2. --- Effects of suspended sediments (SS) on aquatic biota --- p.3 / Chapter 1.3. --- Histopathological biomarkers in fish --- p.7 / Chapter CHAPTER TWO --- INTRODUCTION --- p.20 / Chapter CHAPTER THREE --- MATERIALS AND METHODS --- p.23 / Chapter 3.1. --- Sediments --- p.23 / Chapter 3.1.1. --- Sediment sampling sites --- p.23 / Chapter 3.1.2. --- Sediment collection and handling --- p.25 / Chapter 3.1.3. --- Chemical analysis of sediments --- p.25 / Chapter 3.2. --- Collection and maintenance of fish --- p.26 / Chapter 3.3. --- Sediment bioassays for groupers (E. coioides) --- p.28 / Chapter 3.3.1. --- Preparation of suspended sediments (SS) --- p.28 / Chapter 3.3.2. --- Experimental design --- p.30 / Chapter 3.3.2.1. --- 10-day exposure experiment --- p.30 / Chapter 3.3.2.2. --- 30-day exposure experiment --- p.31 / Chapter 3.3.2.3. --- Time-course and recovery experiment --- p.33 / Chapter 3.3.3. --- Measurement of oxygen consumption and ventilation rates --- p.33 / Chapter 3.4. --- "Tissue sample collection, preparation and examinations" --- p.35 / Chapter 3.4.1. --- Study of sediment clogging --- p.35 / Chapter 3.4.2. --- Scanning electron microscopy (SEM) study --- p.37 / Chapter 3.4.3. --- Histopathological investigations --- p.38 / Chapter 3.4.3.1. --- Histopathology of gills --- p.40 / Chapter 3.4.3.2. --- Histopathology of liver --- p.40 / Chapter 3.4.3.3. --- Histopathology of kidney --- p.41 / Chapter 3.5. --- Sediment bioassays for seabreams (A. schlegeli) --- p.42 / Chapter 3.6. --- Statistical analysis --- p.43 / Chapter CHAPTER FOUR --- RESULTS --- p.44 / Chapter 4.1. --- Chemical analysis of sediments --- p.44 / Chapter 4.2. --- Physicochemical parameters --- p.47 / Chapter 4.3. --- Sediment bioassays for groupers (E. coioides) --- p.49 / Chapter 4.3.1. --- Feeding rate --- p.49 / Chapter 4.3.2. --- Growth rate --- p.49 / Chapter 4.3.3. --- Sediment clogging --- p.53 / Chapter 4.3.4. --- Survival rates --- p.53 / Chapter 4.3.5. --- Oxygen consumption rate and ventilation rate --- p.56 / Chapter 4.3.6. --- SEM study --- p.56 / Chapter 4.3.7. --- Histopathological investigations --- p.64 / Chapter 4.3.7.1. --- Histopathology of gills --- p.64 / Chapter 4.3.7.2. --- Histopathology of liver --- p.82 / Chapter 4.3.7.3. --- Histopathology of kidney --- p.94 / Chapter 4.4. --- Sediment bioassays for seabreams (A. schlegeli) --- p.113 / Chapter 4.4.1. --- Survival rates --- p.113 / Chapter 4.4.2. --- Histopathological investigations of gills and liver --- p.113 / Chapter CHAPTER FIVE --- DISCUSSION --- p.122 / Chapter 5.1. --- Hypoxic effects of SS on histopathology --- p.122 / Chapter 5.2. --- Synergistic effects between SS and chemical --- p.126 / Chapter 5.3. --- Effects of gill impairment on biological responses --- p.131 / Chapter 5.4. --- Reparability of histopathological alterations --- p.135 / Chapter 5.5. --- Species differences in sensitivity to SS --- p.135 / Chapter 5.6 --- Recommendation --- p.136 / Chapter CHAPTER SIX --- CONCLUSION --- p.138 / APPENDICES --- p.140 / REFERENCES --- p.149

by Tse Ching Yee Carol. / Thesis submitted in: September 2005. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (leaves 75-90). / Abstracts in English and Chinese. / Abstract --- p.ii / 摘要 --- p.iv / Acknowledgments --- p.vi / Table of contents --- p.vii / List of tables X / List of figures --- p.xii / Chapter 1.0 --- Introduction --- p.1 / Chapter 1.1 --- Sediment pollution in Hong Kong --- p.1 / Chapter 1.2 --- Impact of suspended sediment on fish --- p.2 / Chapter 1.3 --- Biochemical responses to pollution --- p.3 / Chapter 1.3.1 --- Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) --- p.4 / Chapter 1.3.2 --- Creatine kinase (CK) --- p.5 / Chapter 1.3.3 --- Ethoxyresorufin O-deethylase (EROD) --- p.6 / Chapter 1.3.4 --- DNA damage --- p.8 / Chapter 1.4 --- Study of recovery --- p.10 / Chapter 1.5 --- Objectives and significances --- p.11 / Chapter 2.0 --- Materials and Methods --- p.13 / Chapter 2.1 --- Study sites --- p.13 / Chapter 2.2 --- Sediments collection and handling --- p.13 / Chapter 2.3 --- Measurement of heavy metals and organic contents of sediment --- p.15 / Chapter 2.4 --- Exposure tests --- p.16 / Chapter 2.4.1 --- Test organisms --- p.16 / Chapter 2.4.2 --- 10- and 30-day exposure experiments --- p.18 / Chapter 2.4.3 --- 20-day exposure and recovery experiment --- p.19 / Chapter 2.5 --- Biochemical responses --- p.19 / Chapter 2.5.1 --- "Aspartate aminotransferase (AST), alanine aminotransferase (ALT) and creatine kinase (CK) activities" --- p.19 / Chapter 2.5.2 --- Ethoxyresorufin O-deethylase activity (EROD) --- p.20 / Chapter 2.5.3 --- DNA damage --- p.21 / Chapter 2.5.4 --- Statistical analysis --- p.22 / Chapter 3.0 --- Results --- p.24 / Chapter 3.1 --- Physical and chemical parameters --- p.24 / Chapter 3.2 --- Pollutants in sediment --- p.24 / Chapter 3.3 --- Mortality --- p.28 / Chapter 3.4 --- Biochemical responses --- p.31 / Chapter 3.4.1 --- 10- and 30-day exposure experiments --- p.31 / Chapter 3.4.2 --- 20-day exposure and recovery experiments --- p.50 / Chapter 4.0 --- Discussion --- p.58 / Chapter 4.1 --- "Sediment pollution at Port Shelter, Mirs Bay and Victoria Harbor" --- p.58 / Chapter 4.2 --- Biochemical responses --- p.59 / Chapter 4.2.1 --- 10- and 30-day exposure experiments --- p.59 / Chapter 4.2.1.1 --- "AST, ALT and CK" --- p.59 / Chapter 4.2.1.2 --- EROD --- p.63 / Chapter 4.2.1.3 --- DNA damage --- p.67 / Chapter 4.2.2 --- 20-day exposure and recovery experiments --- p.69 / Chapter 5.0 --- Recommendations and conclusions --- p.73 / References --- p.75 / Appendix --- p.91

Estuarine circulation and its associated transport processes drive the environmental integrity of many near-shore habitats (the coastal ocean, rivers, estuaries and emergent wetlands). A thorough understanding and consideration of this circulation is, therefore, vital in the proper management of these habitats. The aim of this study is to bring together theory and new satellite observations in the Columbia River Estuary to increase our understanding of estuarine circulation and transport. Surface reflectance measurements gathered by the Moderate Imaging Spectroradiometer (MODIS) are first compared to in situ observations to develop an empirical model for remotely derived surface turbidity. Results indicate that MODIS data significantly correlate with in situ measurements of turbidity throughout the CRE (R2 = 0.96). Remote estimates of turbidity are then used to explore the physical processes that drive their spatial distribution. Although the response to different hydrodynamic conditions varies throughout the system, global levels of turbidity are most sensitive to fluvial and tidal inputs and increase during spring tides and high river flow. As a result, the turbidity field has temporal cycles that are consistent with the frequency of these processes. The location of the estuarine turbidity maximum (ETM) is highly dynamic and typically migrates downstream as the tidal velocity or river flow increases. The ETM becomes trapped near the Megler Bridge (river kilometer 20), however, and the presence of strong topography in this region suggests there exists an interaction between bottom topography and sediment transport. A 2-D semi-analytical model, developed herein from the simplified Navier-Stokes equations, confirms that topographic features exhibit substantial influence on longitudinal turbidity distributions. The model considers the coupled, tidally-averaged velocity (composed of gravitational circulation, internal tidal asymmetry, and river flow) and salinity fields and assumes a condition of morphodynamic equilibrium to estimate the distribution of sediment for arbitrary channel configurations. Model simulations demonstrate that topographic highs tend to increase local seaward sediment fluxes, and that topographic lows increase local landward sediment fluxes. Sediment flux convergence near topographic highs compresses the local turbidity distribution, whereas flux divergence near topographic lows dilates the distribution and, under appropriate conditions, produces multiple ETMs. In summary a combination of the model and satellite data has given valuable new insights into the sediment dynamics of estuarine environments; in particular, both show that turbidity distribution and ETM location vary considerably with tidal and river flow conditions, fluctuating on a variety of timescales, and are heavily influenced by bottom topography.

This thesis deals with the role of precipitation on erosion and landscape formation in the Nepal Himalayas. I investigate all successive steps involved in the erosion process: 1) Starting from the evaluation of precipitation datasets, 2) the transfer of precipitation to river discharge, 3) the mobilization and transport of material out of the mountain range, 4) and finally, erosion constrains over longer time-scales. I show that the dataset derived from the interpolation of rain gauge data performs best in the Himalayas. I demonstrate the importance of an until now unconsidered, major compartment of the Himalayan discharge cycle, which I identify as a fractured basement aquifer, and estimate the snow and ice melt contribution to the Himalayan rivers. Erosion rates calculated from suspended sediment fluxes and cosmogenic nuclide analysis range between 0.1 and 4 mm/yr. The rivers in the Nepal Himalayas are supply limited and the hillslopes as contributing source are transport limited. Last I show that over several thousand years erosion is not related with precipitation, but with relief. / Cette thèse porte sur le rôle des précipitations sur l’érosion et la formation des reliefs dans l’Himalaya Népalais. J’étudie chaque étape du processus d’érosion : 1) Evaluation des bases de données de précipitations, 2) Transfert des précipitations au débit fluvial, 3) Mobilisation et transport du matériel dans le bassin versant, et enfin 4) Mécanismes d’érosion sur de longues échelles de temps. Je montre que la base de données de précipitations obtenue par interpolation de données pluviométriques est la plus performante pour la région de l\'Himalaya. Je démontre l’importance d’une composante majeure, jusqu’alors ignorée, du cycle de débit de l’Himalaya que j’identifie comme étant les aquifères de sous-sol fracturé, et j’évalue la contribution de la fonte des neiges et glaces aux rivières Himalayennes. Les taux d’érosion calculés à partir des flux de sédiments en suspension et des analyses de nucléides cosmogéniques varient de 0.1 à 4 mm/a. Les rivières au Népal sont limitées par l’apport sédimentaire alors que les versants, en tant que source de sédiments, sont limités par le transport. Enfin, je montre que l’érosion sur des milliers d’années ne dépend des précipitations mais du relief. / Die vorliegende Arbeit beschäftigt sich mit der Rolle des Niederschlag bei Erosions- und Oberflächenprozessen im nepalesischen Himalaja. Ich untersuche die Abfolge der Erosionspsozesse im Himalaja: 1) Ausgehend von der Bewertung von Niederschlagsdatensätzen, 2) die Prozesse der Abflussbildung in Flüssen, 3) die Mobilisierung und Transport von Material, 4) und Erosionsraten über längere Zeiträume. Ich zeige, dass interpolierte Niederschlagsdaten die beste Qualität im Himalaya haben. Ich zeige auf, wie wichtig der bislang unberücksichtigt Grundwasserzwischenspeicher für die Abflussbildung im Himalaya ist und schätze den Anteil der Schnee-und Eisschmelze an dem Gesamtabfluss der Flüssen im Himalaja. Erosionsraten die mittels Schwebestofffracht und der Analyse kosmogener Nukluide berechnet wurden, liegen zwischen 0,1 und 4 mm pro Jahr. Der Sedimenttransport in den Flüssen in Nepal ist limitiert durch die Verfügbarkeit von transportierbarem Material, während der Transport und die Mobilisierung auf den Hängen durch die Verfügbarkeit von Wasser limitiert ist. Zudem sind die Erosionsraten über mehrere Jahrhundert nicht von der Niederschlagsverteilung abhängig sondern vom Relief.

Suspension flows in varied settings and at different concentrations of particles are studied theoretically using various modeling techniques. Particulate suspension flows are dispersion of particles in a continuous medium and their properties are a consequence of the interplay among hydrodynamic, buoyancy, interparticle and Brownian forces. The applicability of continuum modeling techniques to suspension flows at different particle concentration was assessed by studying systems at different time and length scales. The first two studies involve the use of modeling techniques that are valid in systems where the forces between particles are negligible, which is the case in dilute suspension flows. In the first study, the growth and progradation of deltaic geologic bodies from the sedimentation of particles from dilute turbidity currents is modeled using the shallow water equations or vertically averaged equations of motions coupled with a particle conservation equation. The shallow water model provides a basis for extracting grain size and depositional history information from seismic data. Next, the Navier-Stokes equations of motion and the convection-diffusion equation are used to model suspension flow in a biomedical application involving the flow and reaction of drug laden nanovectors in arteries. Results from this study are then used prescribe the best design parameters for optimal nanovector uptake at the desired sites within an artery. The third study involves the use of macroscopic two phase models to describe concentrated suspension flows where interparticle hydrodynamic forces cannot be neglected. The isotropic form of both the diffusion-flux and the suspension balance models are solved for a buoyant bidisperse pressure-driven flow system. The model predictions are found to compare fairly well with experimental results obtained previously in our laboratory. Finally, the power of discrete type models in connecting macroscopic observations to structural details is demonstrated by studying a system of aggregating colloidal particles via Brownian dynamics. The results from the simulations match experimental shear rheology and also provide a structural explanation for the observed macroscopic behavior of aging. / text