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海滩养护工程实施后,在保护海岸抵御侵蚀的同时往往还产生其他的环境问题。尤其在强风区海岸,海滩养护造成了滩面环境的改变,使滩面风沙搬运和沉积特征都发生了显著变化。对福建平潭岛龙凤头海滩养护工程实施前后的风沙沉积对比研究表明,养护后海滩的干滩宽度、滩面沉积物粒径、表层湿度、海滩高程等环境要素变化对滩面风沙搬运与沉积过程都产生了重要的影响。主要结论为:(1)养护海滩干滩滩肩高程的提高增加了滩面风速,增大了滩面风沙输沙率;(2)养护海滩干滩宽度的增加既扩大了风区长度也为风沙搬运提供了充足的物源,且不受潮汐过程影响,提供了持续的风沙物源供给,增加了风沙作用时间;(3)养护海滩剖面形态的变化使得海滩滩面沉积物含水率减小,降低风沙起动风速,增强了滩面风沙搬运。
After the beach conservation project is implemented, other environmental problems often arise while protecting the coast from erosion. Especially in the coastal areas with strong winds, beach maintenance has led to changes in the beach environment, resulting in significant changes in the wind-sand handling and sediment characteristics on the beach surface. The comparison of aeolian sediment deposition before and after the implementation of Longfengtou Beach Conservation Project in Pingtan Island of Fujian Province shows that the variation of environmental factors such as dry beach width, beach sediment particle size, surface humidity and beach elevation after beach conservation, The process has had a significant impact. The main conclusions are as follows: (1) The increase of the shoulder elevation of dry beach increased the wind speed of beach surface and increased the sand transport rate of sand beach. (2) The increase of the beach width of beach maintenance expanded the length of wind area Aeolian sand handling provides ample source of material and is not affected by the tidal process, providing a continuous source of aeolian sand and increasing the aeolian action time. (3) Changes in the morphology of the conservation beach make the beach surface sediment moisture content reduced , Reducing the wind speed and wind speed, increasing the beach sand handling.