海南岛新海湾海滩地貌状态与海岸泥沙纵向运动特征

根据１９９０年现场调查及前期观察资料，论述了海南岛新海弧形海湾不同岸段由主要动力驱动过程和海滩地貌结构组成的４种海滩地貌状态，为Ⅰ．隐蔽段消散类型，Ⅱ．脊－沟体系与低潮台地类型，Ⅲ．韵律海滩与砂坝类型，Ⅳ．开敞段消散类型。应用泥沙粒级参数概率模型分析近岸泥沙纵向运动趋势，结果表明，常波况下，沿岸泥沙存在双向运动，湾顶海滩为汇集地带，泥沙纵向运动主趋势为西南向；高能条件下，海岸北段可出现北向泥沙运动

GEOMORPHOLOGICAL TYPES OF BEACH AND THE CHARACTERISTICS OF SEDIMENTS LONGSHORE MOVEMENT IN ARC-SHAPED BAY OF XINHAI BAY, HAINAN ISLAND

Based on field investigations in 1990 and some earlier observational data, this paper describes four beach geomorphological types characterized by the main coastal processes and associated beach geomorphological features in different sections of the arc-shaped bay of Xinhai of Hainan Island. The identified beach geomorphological types are protected dissipative type, ridge-runnel and low-tidal terrace type, rhythmic bar and beach type and open dissipative type.Being consistent with the spatial distribution of geomorphological states, the wave energy of the nearshore increases from the northern zone to southern zone and the boundary between sand and mud extended from the five meter isobath of the north to the deeper water zone of the south. Use of a probability model of sand size parameters to analyze sediment longshore transport trends in different sections and depthes of the shore, showed that a bi-direction movement trend exists under normal wave condition, and the primary trend of the sand longshore transport is south westward. Under high energy condition, there is a northward sand movement along the northern section of the coast.