Study on Yarlung Zangbo River Sediment Distribution

Abstract:

Tibetan Plateau is the highest elevation and the fastest uplift plateau. The fragile ecology and poor soil development, under the extreme environmental factors coupling freezing and thawing, weathering, and rainfall, provides a lot of materials for erosion. On the other hand, a large amount of runoff from glaciers and melting snows with considerable drop height keeps flushing and transporting the crushed materials. For these reasons, the soil erosion in the region is widely distributed. The erosion processes are complex with multiple forcing sources and the river sediment is of great variability spatially. The spatial distribution of river sediment is able to reflect erosion sources and erosion intensities. Due to the harsh natural environment of the plateau, however, historical hydrological data and observation stations are scarce. Especially, the river sediment records are hardly to track. Therefore, it is necessary to launch the field investigation of sediment distribution in main rivers in the Tibetan Plateau. The Yarlung Zangbo River is the longest river in Tibetan Plateau and the highest river in the world. It flows from west to east across the southern section of the plateau, covering 912,000 km² basin areas. In the study, field investigation is carried out for sediment distribution along the Yarlung Zangbo River for two years. The investigation involves different elevation segments and main confluences. The data results will be helpful for understanding the temporal and spatial distribution of river sediments and identification of critical erosion areas for further processes-based studies. It will benefit soil erosion classification and the best management practices as well.