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Physics of estuaries and coastal seas
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Variations in water and sediment discharge in rivers along the east coast of the Liaodong Peninsula over the last millennium
P-P1-05-S
Hui Sheng* , State Key Laboratory of estuarine and coastal research,East China Normal University
Jianhua Gao, Key Laboratory of coastal and island development, Nanjing University
Yaping Wang, State Key Laboratory of estuarine and coastal research,East China Normal University
Presenter Email: ShenghuiNJU@163.com |
| Under the increasing impact of rising sea levels, ground surface subsidence and anthropogenic sediment trapping the coastal wetland, large delta and coastal zone are drowning, living 60% of the world’s population. The sediment delivered by the global river systems paly the key roles to prevent the situation. In order to identify the forcing factor and quantify isolated the impact of climate change and human activities on water and sediment to coastal ocean, the hydrologic data of five rivers along the east coast of the Liaodong Peninsula and Hydrotrend V.3.0 were applied. Simulation results indicate that the water discharge and sediment load of the five rivers during the past millennium reached 27.88 km3 yr-1 and 5.97 Mty-1, and Climate change was the most significant forcing factor altering the water discharge in the study area, with human activity having an insignificant effect on the accumulation of freshwater discharge. However, the variations in the sediment load were dominated by human activity. Quantify isolation demonstrated that the soil erosion of the five rivers induced by human activity amounted to 1.04 Mty-1 in the past millennium, and the total trap efficiency of the eastern Liaodong Peninsula was 71.7%. If no dams were constructed in the study area during 1941-2012, the total sediment load of the five rivers would have reached 11.33 Mty-1. This reflects an increase of 92.6% relative to 1000-1850 (5.88 Mty-1) and was 3.5 times the actual sediment load during 1941-2012 (3.21 Mty-1). Consequently, when we investigated the geomorphic evolution, the sedimentary and ecosystem of estuaries and coastal zones, the long-term water and sediment discharge must be considered not just the measured data. The sediment load of five rivers (middle to high latitudes) is dominated by human activities, unlike the tropical zone dominated by combined of climate (tropical-cyclone) and human activities (Dams). Identify the rapid changing of sediment change in short period impact on the coastal system is a new challenge. |
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