黄河入海泥沙对渤海和黄海沉积作用的影响

渤海平均水深18m，最大水深70m，是一个较浅的海湾。黄海平均水深38m，其中部为水深大于50m的盆地。它们的共同特征是陆地环绕。沿岸河流输沙特征对沉积作用过程有重大影响，特别是黄河入海泥沙的影响尤为显著。关于黄河人海泥沙对渤海和黄海沉积作用的影响，前人已从不同角度进行过讨论。黄河是世界上著名的多沙性河流。由于黄河尾闾长期以来不断发生变迁，纵横摆动于华北平原之上，交替注入渤海和黄海，因此，在讨论黄河入海泥沙在中国近海沉积中的作用时，必须把渤海和黄海作为一个整体，甚至南涉东海。本文试图在以往工作的基础上，概括讨论黄河入海泥沙对渤海和黄海海底沉积作用的影响。

STUDY OF THE INFLUENCE OF SEDIMENT LOADS DISCHARGED FROM HUANGHE RIVER ON SEDIMENTATION IN THE BOHAI AND YELLOW SEAS

During 1951-1980, the annual average amount of sediment loads discharged from the Huanghe River is 1069×106 t/a, which accounts for around 80% of the total sediment load emptied into the Bohai sea and Yellow Sea from rivers except the Changjiang River. It shows that sediment loads discharged from the Huanghe River play the most important role in the sedimentation in this area. However, intensities of their influences were different at different places. About 70% of the total sediment loads from the Huanghe River settled down at the mouth and nearby area and the rest spread toward the sea under influence of the tidal current and wave. In the investigation area, characteristic of sedimentation is unequilibrium, which led different sediments formed at different time to distribut on sea bottom.Sediment loads discharged from the Huanghe River were predominantly loess with abundant CaCO3, which can be used to distinguish their dispersion range and intensity. Their mineral assemblage further indicate the influence of the sediment loads derived from the old and the present Huanghe River.Investigation indicates that the influence of sediment loads derived from the Huanghe River on the Bohai Bay and on the center of the Bohai Sea is stronger than on the Laizhou Bay. The spatial distribution of suspended matte:r, which indicates the transport processes of sediment loads discharged from river, has proved this conclusion. The annually average amount of sediment emptied into the Yellow Sea through the Bohai Strait is estimated to be about 5-10 million tons. Most of that was transported round the Chengshan Cape to the west along the south coast of the Shandong Peninsula to the Laoshan Bay. A small part of that was dispersed to the center of the Yellow Sea and deposited together with sediments derived from other sources forming fine grain sediment there, and the rest was tranported to the East China Sea.