River dissolved

Fig. 9-8 Histogram of dissolved solids of samples from the Orinoco and Amazon River basins and corresponding denudation rates for morpho-tectonic regions in the humid tropics of South America (Stal-lard, 1985). The approximate denudation scale is calculated as the product of dissolved solids concentrations, mean armual runoff (1 m/yr), and a correction factor to account for large ratios of suspended load in rivers that drain mountain belts and for the greater than average annual precipitation in the lowlands close to the equator. The correction factor was treated as a linear function of dissolved solids and ranged from 2 for the most dilute rivers (dissolved solids less than lOmg/L) to 4 for the most concentrated rivers (dissolved solids more than 1000 mg/L). Bedrock density is assumed to be 2.65 g/cm. (Reproduced with permission from R. F. Stallard (1988). Weathering and erosion in the humid tropics. In A. Lerman and M. Meybeck, Physical and Chemical Weathering in Geochemical Cycles," pp. 225-246, Kluwer Academic Publishers, Dordrecht, The Netherlands.)...

Meybeck, M. (1987). Global chemical weathering of superficial rocks estimated from river dissolved loads. Am.. Sci. 287, 401-428. 

Figure 24. Drawing of the continuous leaching model used by Vigier et al. (2001) to estimate the residence time of particles in the soils of the Mackenzie Basin, and the related equations. This model assumes that particles are continuously leached in the soil before leaving to the river. Dissolved load of the river integrates the present leaching of the whole soil profile. 238, 234, 230 and 226 are the leaching coefficients of h and Tla nuclides, respectively, and x is the duration of the chentical...

Water is the greatest solvent. It dissolves a variety of substances. Water in the rivers dissolve salts in... 

Table 9.10. Sources of river dissolved load carried to the oceans (in percent of total amount derived from weathering). (After Meybeck, 1987.)...

SOURCES, SINKS, AND CONTROLS OF RIVER-DISSOLVED MATERIAL... 

Sources, Sinks, and Controls of River-dissolved Material... 

Figure 1 Graphical representation of the order of magnitude of natural trace-element concentrations in the river dissolved load. World average values derived from Table 1.

The abundances of trace elements in rivers depends both on their abundances in the continental crust and their mobility during weathering and transport. In order to depict a global solubility trend of trace elements, dissolved concentrations (Cw) are normalized to those of the upper continental crust (Cc) (Figure 2). Data from the continental crust are from Li (2000). In this figure, major elements in river waters are also shown and all normalized concentrations are compared to the value for sodium. It is important to note that the Cw/Cc ratio is a global mobility index rather than a solubility index because, as will be shown below, a number of very different processes contribute to the occurrence of trace elements in river dissolved load. In addition, for a... 

Rivers (dissolved inorganic carbon) 0.39-0.44 Berner et al., 1983 Berner and Berner, 1987 Meybeck, 1987 Drever et al., 1988... 

Rivers-dissolved organic carbon 0.21-0.22 Meybeck, 1981 Meybeck, 1988 Spitzy and Leenheer, 1991... 

Although particulates that are predominantly clay mineral in content are important attenuators of UVR in turbulent streams and rivers, dissolved and particulate organic substances largely control the penetration of UV into most lakes and the sea. Hence, this discussion of the carbon cycle begins with a discussion of the interactions of U V with CDOM, with emphasis on the optical properties of aquatic ecosystems and penetration of solar UVR into the water (see also Chapters 3 and 6). 

From rivers (dissolved inorganic-t organic nitrogen) ... 

F24(d) soil surface ocean (river dissolved P flux)" 0.032-0.058 ... 

Worral, F. and T. P. Burt. 2004. Time series analysis of long term river dissolved organic carbon records. 

Stubbins, A., Spencer, R.G.M., Chen, H., Hatcher, P.G., Mopper, K., Hemes, P.J., Mwamba, V.L., Mangangu, A.M., Wabakanghanzi, J.N., and Six, J. (2010). Illuminated darkness Molecular signatures of Congo River dissolved organic matter and its photochemical alteration as revealed by ultrahigh precision mass spectrometry. Limnol. Oceanogr., 55(4), 1467-1477. 

Molecular signatures of Congo River dissolved organic matter and its photochemical alteration as revealed by ultrahigh precision mass spectrometry. Limnol. Oceanogr., 55(4), 1467-1477. 

Hefner, K.H., Fisher, J.M., and Ferry, J.L. (2(X)6). A multifactor exploration of the photo-bleaching of Suwannee River dissolved organic matter across the freshwatersaltwater interface. Environ. Sci. Technol., 40(12), 3717-3722. 

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