Regional variation of sediment load of Asian rivers flowing into the ocean

Study of Asian major rivers discharge to the ocean reveals variations of th eir water discharges and sediment loads, and local characteristic of river sediment concentrations. On the basis of this, the Asian rivers can be divi ded into three regions: Eurasia Arctic, East Asia, Southeast and South Asia Region. The Eurasia Arctic Region is characteristic of the lowest sediment concentration and load, while the East Asia Region is of the highest sedim ent concentration and higher sediment load, and the Southeast and South Asi a Region yields higher sediment concentration and highest sediment load. The sediment loads of these regions are mainly controlled by climate, geomo rphology and tectonic activity. The Eurasia Arctic rivers have large basin areas and water discharge, drain low relief which consist of tundra sedimen t, thus causing the lowest sediment load. The East Asia rivers have small b asin areas and lowest water discharges, drain extensive loess plateau, and transport most erodible loess material, which results in highest sediment c oncentration. The Southeast and South Asia rivers originating from the Tibe tan Plateau have large basin areas and the largest water discharges because of the summer monsoon and high rainfall influence, causing the highest sed iment load. In Asia, the tectonic motion of the Tibetan Plateau plays an important role . Those large rivers originating from the Tibetan Plateau transport about 5 0% of the world river sediment load to the ocean annually, forming large es tuaries and deltas, consequently exerting a great influence on sedimentatio n in coastal zones and shelves.