朱家尖南沙海滩剖面变化特征与泥沙输运

在对朱家尖岛南沙海滩的沉积环境、动力条件、地形地貌进行调查与监测的基础上，利用不同的波能流公式对海岸的沿岸泥沙运动进行计算与分析。结果表明:该海滩沉积物以沙为主，物质来源主要是邻近的海岸基岩风化侵蚀产物；受海岸波浪、潮汐、潮流等动力条件和沉积环境综合作用的影响，海滩剖面地形的季节性变化明显:夏季侵蚀、冬季淤积；海滩东侧侵蚀、西部淤积的年际变化特点与沿岸输沙密切相关；沿岸输沙计算结果显示各岸段沿岸净输沙量平均值介于43.85×10³~172.77×10³ m³/a；自东向西的沿岸输沙主要由ESE、SE向的入射波所致，自南向北的沿岸输沙由S向入射波所致，在不考虑人类活动对海滩影响的情况下，沿岸输沙在海滩长期的演化过程中起到了关键作用。

Profile variation characteristics and sediment transport of Nansha beach in Zhujiajian

Based on the investigation and monitoring of sedimentary environment, dynamic conditions and topography of the Nansha beach in Zhujiajian, the longshore sediment transport is calculated and analyzed by using different wave energy flow methods. The results show that the main type of beach sediments is sand, and the depositional substance is mostly from efflorescent rock. Affected by waves, tides, tidal currents and sedimentary environment, the seasonal variation of beach profile is obvious, which is the erosion in summer and the deposition in winter. The characteristic that is erosion in the east and deposition in the west is closely related to the coastal sediment transport. The calculation results of longshore sediment transports show that the net volume of sediment transport is between 43. 85×10³ m³/a and 172. 77×10³ m³/a. The direction of longshore sediment transport from east to west is mainly caused by ESE and SE incident waves, and the direction from south to north is caused by S incident waves. Without considering the impact of human activities on the beach, the longshore sediment transport plays a key role in the long-term evolution.