Dissolved load

Dissolved load is material, especially ions from chemical weathering, that are carried in solution by a stream. The dissolved load contributes to the total amount of material removed from a catchment. The amount of material carried as dissolved load is typically much smaller than the suspended load, though this is not always the case particularly when the available river flow is mostly harnessed for irrigation, industrial, etc. purposes. Dissolved load comprises a significant portion of the total material flux out of a landscape, and its composition is important in regulating the chemistry and biology of the stream water.

Dissolved load is one of three types of stream load, along with suspended load and bed load.

The dissolved load is primarily controlled by chemical weathering, which depends on climate and weather conditions such as moisture and temperature.[1]

Salt export

The process of carrying salts by water to the sea or a land locked lake from a river basin is called salt export. When adequate salt export is not taking place, the river basin area particularly in lower reaches gradually converts into saline soils and/or alkali soils.[2] The salt export from the major rivers are

Salt export of important rivers
River@Mean annual flow to the seaDrainage areaDissolved loadSuspended load
Billion cubic meters1000 km2Million tons/yrMillion tons/yr
Amazon55006300287900
Yangtze1,0631,950226478
Orinoco94695050210
Mekong66679559160
Mississippi5803,267131210
Brahmaputra51058051597
Ganga25075084329
Irrawaddy42243090285
Magdalena23624028220
Indus321,16546100
Godavari7531017170
Yellow River48745221,080
Krishna24257121.74
Kavery8883.50.04
All rivers31,400101,0003,60013,505

@ includes water transfer to other river basins

See also

References

  1. ↑ Grosbois, C.; Négrel, Ph.; Fouillac, C.; Grimaud, D. (2000). "Dissolved load of the Loire River: chemical and isotopic characterization". Chemical Geology. 170 (1–4): 179–201. doi:10.1016/s0009-2541(99)00247-8. ISSN 0009-2541.
  2. ↑ "Hydronomic Zones for Developing Basin Water Conservation Strategies" (PDF). Retrieved 12 July 2015.

USGS CMG InfoBank: Suspended and Dissolved Loads


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