| Transport and accumulation of suspended sediment in the shelf seas are not onlycritical to the morphology and topography of coastal region, but also of importance tomairne biogeochemical cycles and ecological environment due to the adsorptioneffect of ifne-grained sediment to vairous nutirents and particulate pollutants. TheBohai Sea and Yellow Sea is a typical system with active sediments transport giventhe environmental factors such as a wide continental shelf with complex circulationpattern，typical mud deposits and monsoon actions, as well as important terrestiralmateirals input from the Yangtze River and the Yellow River. The sediment transportin the Yellow Sea and Bohai Sea is thus of significance to understanding evolution ofregional morphology and coastal ecosystem.Based on data set of suspended sediment concentration, as well as marinehydrology parameters collected by CTD recorder，the suspended sediment distirbutionwas analyzed both laterally and vertically in Bohai Sea and the Yellow Sea, whichwas supported by the National Natural Science Foundation of Public voyageincluding six cruises rfom2010to2012. An empirical model was established toretireve monthly averaged SSC in Bohai Sea and the Yellow Sea based on the Band4reflectance intensity of the MODIS LIB data and the corresponding measuredsuspended sediment concentration. The seasonal vairation of suspended sediment inBohai Sea and the Yellow Sea was studied based on the in-situ data and the retrievedresults. The diffusive flux in main section of the Bohai Sea and the Yellow Sea wasanalyzed by the use of others simulated current velocity data and measured SSC ineach layer. The results show that:High SSC areas were observed in Bohai Sea and the Yellow Sea, namely, aroundthe Yellow River Estuary, the region rfom the Subei shoal to the Yangtze RiverEstuary, the Shandong Peninsula coast especially the Chengshantou cape area, nearNaju Islands as well as other small irver estuaires. The vertical structures of water column in Bohai Sea and the Yellow Seapresented significant seasonal vairability. In summer season，the difference intemperature between the upper and lower layer becomes high with waekhydrodynamics, and the concentration of the suspension sediment is relatively low. Inwinter season when the strong northesterly winds are prevailling, the sea temperatureis low, the difference in temperature between the surface and bottom layers becomeslow because of the strong vertical mixing induced by winds and wave actions.Meanwhile, the currents system, such as the Yellow Sea Warm Current and the coastalcurrent around the Shandong Peninsula, is strengthened, with the sediment transportcapacity and efficiency greatly improved, making the winter season to be the maintransport season for suspended sediment.The suspended sediment flux of the main sections of the coast of the ShandongPeninsula:0.33t/s for Laizhou Bay section,0.55t/s for the Bohai Strait section,3.5t/s for the B4section in northern Shandong Peninsula,3.2t/s for the B2section of theeastern part of Shandong Peninsula,2.6t/s for B1section,1.5t/s for the BO section inthe southeast of the Shandong Peninsula section. The spatio-temporal distirbutionpattern of suspended sediment and the section flux intensity suggests that: the muddeposition area near the Shandong peninsular expeirenced strong resuspension understrong dynamic conditions in winter season. The suspended sediment was transportedsouthward by the coastal current, bypassed the peninsular, and then deposited at thesouth of the peninsular. Compared with the location of the muddy depo-center of theShandong Peninsular, the present depo-center might shitf southward. Thus，theShandong peninsular mud center, which is under significant erosion，is no more than adepo-center for the sediments from the modern Yellow River. Nevertheless, more dataof sediment dynamics and bathymetry are needed to conifrm the speculation. |
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