利用野外调查、遥感地貌解译、地理信息系统、基于海图数字化的DEM等方法,研究了最近40年来乳山湾海岸地貌、海岸线和地貌冲淤状态演变,分析了人类活动特别是大面积滩涂养殖对海岸地貌演变的影响。结果表明,在大规模人类活动发生以前,乳山湾潮流过程处于涨潮不对称控制状态,海湾地貌总体上处于淤积状态,地貌演变的总趋势是水域向潮滩、潮滩向海积平原转变。在最近40年里,乳山湾潮滩被大面积开发为养殖池,在潮滩和海积平原之间出现了一条人工地貌带——养殖池,阻断了原有的物质交换模式。其结果是,乳山湾海岸地貌发生显著改变,海湾虽仍处于涨潮不对称状态,但不对称性程度显著减弱,导致海湾淤积速率减缓,地貌冲淤状态向冲淤平衡甚至侵蚀状态转变。因此,最近40年来人类活动在乳山湾地貌演变过程中起着十分重要的作用,深刻改变了原有的地貌演化趋势。
Field survey,remote sensing,GIS and DEM based on nautical charts were used to study the change in coastal landforms,coastlines,geomorphology and scouring / silting patterns in the Rushan Bay for the last 40 years so as to trace the impact of human activities,especially large area aquaculture on coastal landforms evolution.The results suggest that before the massive human activities occurred,the Rushan Bay was under the control of an asymmetric flood tide and suffered from siltation in general.Progradational deposition dominated the past 40 years.The water area was filled by sediments and became a marine plain.A large area of tidal flat has been developed as artificial ponds between the tidal flat and marine plain for aquaculture.The original material exchange mode was changed.As the result,the landforms of the Rushan Bay changed notably.Although it was still under the control of the asymmetric flood tide,the asymmetry had significantly decreased,which led to the slowing down of sedimentation or turned to erosion.Therefore,human activities in the recent 40 years have profoundly changed the original landform evolution in the Rushan Bay.