Rivers suspended

Sayles, F. L., and P. C. Mangelsdorf Jr. (1979), "Cation-Exchange Characteristics of Amazon River Suspended Sediment and its Reaction with Seawater", Geochim. Cosmochim. Acta 43, 767-779. 

Other analytical tools have also been used as offline detectors for the FFF techniques. Bio et al. (1995) used for this purpose a graphite furnace atomic absorption spectrometer (GFAAS) to analyze colloidal kaolin particles. Contado et al. (1997) used same design to characterize river-suspended particulate matter of size <1 pm. However, the centrifuges available for SdFFF are only capable of separating particles with sizes down to 80 nm. Usage of SdFFF for characterization of HS is therefore restricted because of this limitation. 

It can be seen in Table 9.7 that the particulate load constitutes by far the most important contribution (88%) of total river discharge of materials to the ocean. The amount carried as solids should be increased by bed load transport, which usually is considered to be about 10% of the total suspended load (Blatt et al 1980). The mean chemical composition of river suspended matter closely approximates that of average shale (Table 9.8). This resemblance is expected because suspended solids in rivers are derived mainly from shales. Sedimentary rocks constitute about 66% of the rocks exposed at the Earth s surface fine-grained rocks, like shales, comprise at least 65% of the sedimentary rock mass. Thus, roughly 50% of surface erosion products come from shaly rocks. 

Table 9.8. Comparison of the average chemical composition of river suspended material, shales and soils.

Table 9.9. Mineralogical composition of river suspended load and shales (wt.%). (After Wollast and Mackenzie, 1983.)...

The mineralogy of the suspended matter carried by rivers is not well documented. There are numerous analyses either of the clay fraction or of sands carried by rivers, but only a few total quantitative analyses are reported in the literature. As examples, the average mineralogical composition of two large river systems, the Amazon and the Mississippi, are presented in Table 9.9. This table also includes the mean mineralogical composition of shales for comparison with river suspended sediments. The overall average of 300 samples of shales analyzed by Shaw and Weaver (1965) is 30.8% quartz, 4.5% feldspar, 60.9% clay minerals, and... 

About 80% of the total water runoff of all the rivers flowing into the Black Sea falls on five the most water abounded rivers the Danube (208 km3 year-1 or 59%), Dnieper (43.4 km3 year-1,12%), Rioni (13.38 km3 year-1,3.8%), Dniester (9.1 km3 year-1,2.6%) and Chorokhi (8.71 km3 year-1,2.4%). Only three rivers are responsible for the most part (67%) of the combined river suspended... 

Figure 3 Loss of terrestrial OC in deltaic systems, (a) Organic carbon to mineral surface area ratio (OC SA) plotted against bulk stable carbon isotopic compositions for riverine suspended sediments (closed symbols) and deltaic surface sediments (open symbols). A shift to lower OC SA values indicates net loss of organic matter, and a shift to heavier (i.e., C-enriched) isotopic compositions indicates increasing contributions from marine organic matter, (b) The average ( 1 SD) total amount of terrestrial OC persisting in deltaic sediments, based on the changes in OC SA and composition between river suspended sediments and deltaic sediments for four river systems...

Fig. 2 Graphs showing " C-glyphosate on river suspended-particulate matter, (a) Particle mass and adsorbate fractograms (b) particle size distribution and pollutant adsorption distribution (c) surface-adsorption density distribution.

Coastal erosion 1 Sediments eroded from cliffs, etc. by waves, tides, storms, etc. Composition similar to river suspended load... 

Rostad CE (1997) From the 1988 drought to the 1993 flood Transport of halogenated organic compounds with the Mississippi river suspended sediment at Thebes, Illinois. Environ Sci Technol 31, 1308-13012. 

Table 3-5 Percentage of Cadmium and Zinc not Released from River Suspended Matter after Treatment with NaCl-Solution (Salomons, 1980)...

Fig. 2 Comparison of SCCP homolog group patterns in the Kasaibashi River (Japan) and nearby Tamagawa (Tokyo) STP effluents [41], St Lawrence river suspended (susp) sediments and dissolved phase [45] and in North Sea sediments [35]. Results from Hiittig and Oehme [35] are combined for their sample 1 (North Sea) and 8 (Baltic Sea)...

A study of Connecticut streams (Turekian, 1971) indicated that the trace metals, cobalt and silver, are maintained at low concentrations in solution as the result of the scavenging action of suspended particles. Even where acid industrial wastes are dumped into the stream, as in the Naugatuck River, which joins the Housatonic River, suspended particles act to lower the dissolved concentrations. We infer from studies involving the behavior of Pb in the Susquehanna River and of Co and Ag in the major Connecticut rivers that the dissolved trace-metal concentration is maintained at low levels in stream water and thus the primary mode of transportation to the estuarine zone is via particles. 

Rivers Suspended Matter Discharge (10 tons/yr) Drainage Area (10 km ) Water Discharge (km /yr) Turbidity of River Water (mg/1) Water Turbidity at the River-Sea Barrier Sedimentation Rate in Delta and Fan (B) Delta-Sediment Thickness, Maximum (km)... 

Fractionation of the lanthanides is often quantified by shale-normalized patterns. Normalization to shale represents an abundance relative to that of the upper crust of the continents. A flat shale pattern for river suspended particles would indicate a composition similar to that of averaged continental crust. To study fractionation in rivers, it is also instructive to normalize the dissolved composition to that of suspended particles on the assumption that the particles better represent the solids being weathered in the watershed. 

Fig. 9. Shale-normalized lanthanide compositions of river suspended particles (>0.22 (tm) of the Amazon, Fly (Papua New Guinea) and Mississippi River waters. See fig. 8 for more details.

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