海阳市典型砂质海岸侵蚀机制与防护对策研究

Coastal erosion mechanism and its prevention in Haiyang

海阳市砂质海岸资源丰富,延绵近120 km,尤以万米沙滩浴场著称,但近年岸滩侵蚀严重影响其社会经济发展。本研究基于海阳市羊角畔两侧长约20 km典型砂质海岸连续3 a的海岸线蚀和典型剖面蚀淤调查,定量化研究海滩侵蚀及其变化,辅以一维数值模型,研究人类活动影响下的泥沙运动特征和海滩侵蚀机制。研究结果表明,调查区42.5%和5.90%的砂质海岸分别处于侵蚀和强侵蚀状态,羊角畔东侧海岸侵蚀强度高于西侧,海阳港至海阳核电厂之间海滩侵蚀强度最高,海滩侵蚀强度与人类活动扰动程度密切相关。海岸工程、临海养殖和人为采砂导致海阳市部分砂质海岸侵蚀严重的主要原因,导致羊角畔两侧海岸侵蚀机制也不同。基于各岸段侵蚀机制特征有针对性地提出退养还滩、凸堤拆除和沙滩喂养等对策,以减缓海阳砂质海岸侵蚀威胁。

There exists a rich sandy coastal resource in Haiyang that is nearly 120 km long and is especially famous for its 10000-meter beach.However,its social and economic developments have been affected by coastal erosion in recent years.Based on sandy coastal erosion observations of a typical 20-km sandy coast near the Yangjiaopan es-tuary for three years,characteristics and changes of beach erosion were quantitatively studied.Sediment motion characteristics and the beach erosion mechanism affected by human activities were studied combined with the one-dimensional numerical model.The result shows that 42.5%and 5.90%of the sandy coast experiences erosion and intense erosion,respectively.The erosion intensity of the east coast of the Yangjiaopan estuary is higher than that of the west,and the erosion intensity between the Haiyang harbor and the Haiyang nuclear power plant is the highest.The sandy coastal erosion intensity is closely related to the intensity of human activities.Therefore,some remedial measures(clearing farms occupying the beach,removing convex dikes,and beach nourishment)to miti-gate the sandy coastal erosion in Haiyang are put forward based on different erosion mechanisms.