Transportation, sediments

The material transported by rivers consists of dissolved ions (dissolved load), sediment suspended in the flow (suspended load), and sediment transported along the bed of the river (bedload). The total load and the proportion of the load represented by these phases varies widely among rivers in different environments. In particular, climate, topography, and erosion influence the amount and composition of riverine sediment loads. 

A fundamental distinction among landscapes is whether the net sediment flux (the total load carried by the river) is limited by the ability of erosional processes to carry sediment (transport-limited environments) or the availability of erodible material (weathering-limited environments). In general, soil-mantled landscapes can... 

Black, T. A. and Montgomery, D. R. (1991) Sediment transport by burrowing mammals, Marin County, California. Earth Surf. Process. Landforms 16, 163-172. 

George R, Turner S, Hawkesworth C, Morris J, Nye C, Ryan J, Zheng S-H (2003) Melting proeesses and flnid and sediment transport rates along the Alaska-Aleutian arc from an integrated U-Th-Ra-Be isotope study. J Geophys Res (in press). 

A survey of available Th data for the ocean basins demonstrated that the highest concentrations are found nearer to the coasts, and it was concluded that while eolian inputs likely dominated the budget in the open ocean and could account for increases near the coast, fluvial inputs may be more important in coastal regions. This implies that some a mechanism causes recycling of Th that has been removed to estuarine sediments (Huh et al. 1989). A study of an ice-covered region of the western Arctic Ocean found that significant amounts of °Th and Th were advected into the basin (Edmonds et al. 1998). Therefore, it appears that while long-lived Th isotopes are rapidly removed into estuarine sediments, transport into the ocean basins may continue. 

Surface water information, including drainage patterns (overland flow, topography, channel flow pattern, tributary relationships, soil erosion, and sediment transport and deposition), surface water bodies (flow, stream widths and depths, channel elevations, flooding tendencies, and physical dimensions of surface water impoundments structures surface water/ groundwater relationships), and surface water quality (pH, temperature, total suspended solid, salinity, and specific contaminant concentrations)... 

Particle Transport. Because many organic chemicals bind with aquatic particulate matter, particle transport can determine the fate of compounds. Sediment transport has been of interest to the engineering profession for many years. Many discussions of the dynamics of fluvial sediment transport have appeared in the literature (11, 12). As with hydrodynamic transport, one strategy for environmental modeling is to "piggy-back the transport of sorbed chemicals on a model of transport of the sediment phase. 

HSPF. The Hydrologic Simulation Program (FORTRAN) ( 1, 42) is based on the Stanford Watershed Model. Version 7 of HSPF incorporates the process models of SERATRA in its aquatic section, with several (user-selectable) options for sediment transport computations. HSPF includes the generation of transformation products, each of which is in turn subject to volatilization, phototransformation, biolysis, etc. 

Garde, R.J. Ranga Raju, K.G. "Mechanics of Sediment Transportation and Alluvial Stream Problems" Wiley New York, 1977 p. 483. 

Simons, D.B. Senturk, F. "Sediment Transport Technology" Water Resources Publ. Fort Collins, Colorado, 1977 p. 807. 

The model is composed by different equations which in all cases can be used in unsubscribed format in a basic language program. An important point to highlight is that Qwasi takes into account both steady and unsteady state solutions for the equations for systems involving contamination of lakes (or rivers). The equations considered by Qwasi involve more than 15 physicochemical processes (such as partitioning, sediment transport, deposition, etc.) to estimate the fate of the studied system. These processes and the main involved variables and parameters are summarized in Fig. 2. 

Vericat D, Batalla RJ (2005) Sediment transport in a highly regulated fluvial system during two consecutive floods (lower Ebro River, NE Iberian Peninsula). Earth Surf Process Land-... 

Keywords Dams, Flow regime, River Ebro, River hydrology, Sediment transport Contents... 

Data on sediment transport in the Ebro basin is very scarce. Besides some historical studies in the lowermost reaches of the catchment (e.g. [21]), almost at the delta plain, and few others undertaken during the 1990s (see Table 1), only the work undertaken by the Fluvial Dynamics group of the University of Lleida (hereafter UdL) between 2002 and 2008 in the lower part of the river supply reliable data on the total sediment load and changes in sediment transport and channel morpho-sedimentary characteristics upstream and downstream from large dams. 

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