摘要
在野外观测和历史地貌调查的基础上,利用地理信息系统和遥感技术,研究了现代莱州浅滩的地貌演变规律和人类活动对浅滩地貌冲淤动态的影响。结果表明,受其特有的沉积动力过程控制,莱州浅滩不断淤高并向东北迁移、西北延伸。1958年以来由于修建水库、码头和海底采沙等人类活动导致泥沙亏损,浅滩在继续向东北迁移、西北延伸的同时,总体上处于侵蚀、解体状态,在中部和近岸部分之间、近岸部分和刁龙嘴海岸之间先后形成了贯通的潮流槽,不同地貌部位冲淤状态存在差异。
Based on field work and historical geomorphic analysis, and supported by GIS and RS, this paper has researched the geomorphic dynamic characteristics and evolution rules and the artificial effects on erosion and deposition of the Laizhou shoal since 1958, when many reservoirs were built, and a great amount of sand began to be reduced. The results show that the Laizhou shoal has been moving northward while the nearby Diaolongzui spit moving northward because of the geomorphic-dynamics between them since the mid-19th century. The sand made up of the shoal has come directly from the Diaolongzui coast, and ultimately from the rivers which empties into the Bohai Sea across the NE direction stretching coast from the Diaolongzui spit to the Qimudao island. There are two main depositional dynamic mechanisms, which have been controlling the shoal erosion and deposition processes. One is that when the ebb tidal current from the south-west Laizhou bay is retarded by the shoal, it turns to flow along the west-northern striking shoal with a secondary transverse circulation made up of shoalward currents in the bottom and upwelling currents near the shoal. So, erosion took place on the SW part, and deposition on the top part of the shoal, which led to the shoal migrating toward NE as a whole. Another is that the centrifugal effect of tidal currents around the pointed end of the shoal causes a secondary circulation made up of shoalward currents in the bottom and upwelling currents in the upper. So, the suspended sand deposits on the NW part of the shoal.
出处
《地理学报》
EI
CSCD
北大核心
2003年第5期749-756,共8页
Acta Geographica Sinica
基金
山东省优秀中青年科学家项目资助(02BS121)~~
关键词
沉积
地貌演变
地理信息系统
莱州浅滩
Laizhou shoal
GIS
geomorphic evolution
deposition dynamic process
human activities
