摘要
中央沙位于长江口南北港分流口河段,这一河段集中了宝钢等一批重要码头,下游有长兴岛造船基地和长江口深水航道等重点工程,因此分流口保持稳定至关重要。以1870年中央沙出现雏形以来的海图为基础资料,利用ArcGIS等GIS软件,研究了中央沙发育演变的位移变化及其典型剖面特征,发现中央沙的变化特点是在长期径流作用下后退和承接上游底沙下泄发生上提的“下移-上提-再下移……”的周期性演变规律。再进一步对南北港分流口各个沙洲近10年来面积和体积进行计算,结合实测水文资料对通道演变进行了分析,认为现阶段长江口南北港分流口处于不稳定时期,应尽早实施分流口整治工程,稳定河势、滩势和减小底沙下泄对下游的威胁。
Zhongyang Sandbank is located on the South and North Passage bifurcation. This section is concentrated with several important projects, such as quay of Shanghai Baosteel Group Corporation and deep-water navigation channel project downstream. Based on topographic maps dating from 1870, utilizing ArcGIS and other GIS software, the paper mainly deals with displacement characters and profile of bifurcation sandbanks including Zhongyang Sandback,Shangliuhe Sandbank and Xinliuhe Sandback and so on. It is found that the evolvement character of Zhongyang Sandbank is ＂back off - upper shift- back off again and so on＂ circulative evolvement of back off under long-term runoff and going up with accepting bottom sand from up-reaches. The area and volume of each sandbank has been calculated, and each channel of the South and North Passage bifurcation has been analyzed. At present, bifurcation is not steady. It is necessary to carry out regulation project as soon as possible in order to stabilize sandbanks and channels and reduce the threat of bottom sand towards downstream.
出处
《长江流域资源与环境》
CAS
CSSCI
CSCD
北大核心
2007年第4期476-481,共6页
Resources and Environment in the Yangtze Basin
基金
国家自然科学基金项目(50179012)资助
关键词
长江河口
中央沙
冲淤计算
南北港分流口
剖面
the Yangtze River Estuary
Zhongyang Sandbank
calculation of erosion and accumulation
South and North Passage bifurcation
profile
