[H-CG26] デルタとエスチュアリー：複雑な河口システムへの学際的取り組み

[HCG26-01] Recent Changes of the Asian Major Deltas

★Invited Papers

*Paul Liu¹ (1.North Carolina State University Raleigh)

キーワード：river delta , sediment decrease , shoreline erosion , subsidence

In the past 50 years, sediments from major Asian rivers have sharply decreased 80-90% due to the increased human activities (like building dams, overusing water, or sand mining) and climatic changes. Many of those river deltas have been experiencing severe coastal erosions, like the Yellow, Red, Mekong, Chao Phraya, and Indus, etc. Most of these deltas have turned from constructive growing mode to destructive declining mode, for example, the Mekong Delta has shown overall negative net land gain starting ~ 2005. Our studies also show not only the deltaic shorelines are retreating, but also some delta’s subaqueous portions are under strong erosion, such as the Yangtze, Mekong, Chao Phraya and Indus, etc.