Dredging entrance channels to ports on open littoral drift seashores often causes major morphological changes to the shoreline. This study aims to assess the impact of dredging the Port of Klaipėda's entrance channel and the construction of the jetties on the coastal zone. Based on an analysis of cartographic material collected between 1835 and 2017, and on field data (bathymetric surveys and cross-shore profile levelling), changes to the coastal zone in the area nearest to the port were evaluated. The dominant longshore sediment transport on the Lithuanian nearshore runs from south to north. Thus, based on established patterns, intensive accretion could have been expected to take place on the southern side of the port jetties and erosion on their northern side. However, in the case of the Port of Klaipėda, in the area nearest to the port on the updrift side of the port jetties, where accretion would have been expected to take place, the nearshore depth increased throughout the 20th century (when the length and configuration of the jetties did not change). The shoreline shifted landward instead of moving further out to sea. The present study shows that the intensive dredging of the entrance channel caused nearshore and shore erosion on the updrift side of the port jetties, even while a sufficient sediment load was being transported by the longshore drift.

开阔的沿海漂泊海滨港口的疏entrance入口通道通常会导致海岸线发生重大形态变化。这项研究的目的是评估疏K克莱佩达港的入口通道和建造码头对沿海地区的影响。基于对1835年至2017年期间收集的制图材料的分析，并根据实地数据（测深调查和跨海岸剖面水准测量），评估了离港口最近的沿海地区的变化。立陶宛近岸的主要近岸沉积物运输从南到北。因此，根据既定的模式，预计在码头的南侧会发生大量积聚，而在码头的北侧则会发生侵蚀。但是，就克莱佩达港而言，在港口码头的上漂侧最靠近港口的区域（预计会发生积水），整个20世纪（码头的长度和构造没有变化），近岸深度有所增加。海岸线向内移动，而不是进一步向海移动。本研究表明，即使在沿岸漂流输送足够的泥沙负荷的情况下，入口河道的密集疏caused也会在港口码头的上流侧造成近岸和岸上的侵蚀。