近十年磨刀门水道咸界运动规律分析

Motion Laws of Saltwater Border in Modaomen Channel in Resent Decade

利用磨刀门水道中多个水文站的观测数据,设计了咸界包络线图,给出0.5‰咸界在磨刀门水道中的运动过程。根据2011—2015年枯季的咸界包络线图和2007—2010年枯季的咸界图,分析近10 a枯季的咸界运动基本特点,得到近10 a磨刀门水道的咸界运动规律:2007—2010年枯季,枯、丰水年隔年交替,咸界上溯距离明显隔年远、近变化;2011年末上游来水特枯,咸界上溯远,咸潮灾害非常严重;2012—2014年枯季,同年内不同半月周期咸界变化较大,有个别周期咸界上溯远,总体上咸潮灾害相对较轻;2015年上游水情非常好,咸界在下游徘徊,始终未达平岗,没有构成咸潮灾害。

With the salinity data from hydrological stations, the 0. 5‰ salinity envelope line figure was designed, which shows the movement of saltwater border in Modaomen channel. According to the salinity envelope line figure in the dry season from 2011 to 2015 and the saltwater border map from 2007 to 2011, the movement characteristics of saltwater border were analyzed and the laws of saltwater border in resent decade were shown： From 2007 to 2010, as different amount of runoff, the intrusion distance was longer in 2007 and 2009 while shorter in 2008 and 2010. In 2011, the amount of runoff was very low, the saltwater intruded very far. From 2012 to2014, the movement of saltwater border was dissimilarity in different cycles of the same year. There is only few cycles that the saltwater border intruded far while in other cycles the saltwater border intruded low. In 2015, the amount of runoff was very large and the saltwater border just stayed downstream and never arrived Pinggang station.