Assessment of sediment transport into Thi Nai lagoon, Binh Dinh province

Abstract

   Thi Nai lagoon is the outlet of two great rivers in Binh Dinh province, that are Kon and Ha Thanhrivers. The change in flow regime and sediment transport from these two rivers have a greatinfluence to the morphology, lagoon ecosystems and the economic activities in Quy Nhon seaport.In this research, the semi distribution hydrological model SWAT is used to assess the flow regime,sediment load at the outlet of Kon and Ha Thanh rivers. The results show that water and sedimentamount flowing to the Thi Nai lagoon are mainly from the Kon river catchment. The averageannual sediment load from Kon River is 549776.32 tons, approximately 82.04% of the sedimentamount loading to lagoon. In addition, the map of soil erosion due to the rain will be built for thesub-catchment in study area. There are 3 levels of soil erosion (strong, moderate and slighterosion) and the most popular level is moderate erosion.