摘要
根据历史和实测资料研究慈溪市海岸变化过程及其成因，结果表明：1）距今约2500a慈溪全境已形成南丘北海、中部为滨海平原的地貌格局；2）慈溪滩涂属于淤涨型滩涂，自宋代以来已修建11道海塘，新中国成立前海岸线平均每年向外推移25m，之后则达到50～100m；3）慈溪滩涂形成演变的影响因子包括地形约束、河川径流和人类活动等，近代人类活动的作用强度越来越大；4）西三闸附近涨潮潮位增高和庵东滩面淤高、扩大是西三潮沟形成的主要动力因素，其诱因是大规模的人类活动。西三潮沟的整治原则应是“因势利导，围涂治沟”。鉴于目前西三潮沟东西两侧都已完成直堤工程，建议在钱塘江连续丰水年时抛石筑坝，彻底截断西三潮沟。
According to analysis of large amounts of historical and actual data, this paper conducted in - depth research in the evolution process and genesis of the Cixi coastline, several important realizations were made as follows： 1）The geomorphic configuration of hilly land in the southern area,sea in the northern area and littoral plain in the middle area,within the overall area of Cixi had already been formed about two thousand and five hundred years ago. 2）Cixi tidal flat belongs to the silting- up type tidal flat. Eleven dikes have already been constructed since the Song dynasty. The average outward migration rate of the coastline was 25 m per year he.fore the foundation of the People＇ s Republic of China and it had been increased to 50-- 100 m per year after the foundation of the People＇ s Repub- lic of China. 3） The influencing factors for the formation and evolution of Cixi tidal flat mainly include landform restriction, river runoff, and human activities. The influence of human activities becomes even greater in modem times. 4）The main dynamic factors for the formation of the tidal furrow are the increase of the tide level of the flood tide near the Xisan sluice and the expansion of aggradations of the Andong beach, and it can be attributed to large- scale human activities. The paper points out that the principle for the regulation of Xisan tidal furrow should guide action according to circumstances. Reclamation of the tidal flat accompanied with the regulation of the tidal furrow should be included. In view of the accomplishment of the dike project along the western and eastern sides of Xisan tidal furrow at present, dam construction by stone riprap could be considered to cut off thoroughly the tidal furrow. The correct timing for dam construction by stone riprap should be selected in the continuous wet year of Qiantangjiang River. This knowledge has some important practical meaning for reclamation and exploitation of Cixi tidal flat.
出处
《地理与地理信息科学》
CSCD
北大核心
2006年第6期75-78,共4页
Geography and Geo-Information Science
基金
浙江省自然科学基金重大项目(ZE0204)
关键词
海岸
慈溪
西三潮沟
人类活动
滩涂围垦
coast
Cixi
Xisan tidal furrow
human activity
tidal flat reclamation
