河北省京唐港附近沙坝—潟湖海岸地貌演化特征

GEOMORPHOLOGICAL EVOLUTION OF THE BARRIER-LAGOON SYSTEM NEAR THE JINGTANG PORT,HEBEI PROVINCE

河北省的沙坝—潟湖海岸,在自然因素和人类活动的双重影响下逐渐消亡,砂质岸线不断蚀退。基于京唐港附近15条海滩剖面2016—2017年夏、冬两季共4次监测结果,开展了剖面地形和表层沉积物粒度的时空变化研究。监测结果显示,海岸整体呈现蚀退,其中永乐岛和明月岛呈侵蚀淤积交替出现;吉祥岛受人为因素影响小,侵蚀严重,残留沙坝2年累计侵蚀10~30m,每年夏季较冬季侵蚀显著。2016年度剖面冬季较夏季沉积物变粗,由于部分剖面沙滩侵蚀严重,淤泥质基底出露,沉积物变细。

The barrier-lagoon coast of Hebei province is gradually varnishing by both natural factors and human activities,and the sandy coastline is continuously eroding.Based on 4 times of monitoring for 15 beach profiles near the Jingtang Port in summer and winter seasons,the spatial and temporal variation in geomorphology and grain size distribution pattern of the surface sediment was studied.The results show that the coast is now under erosion as a general trend.Erosion and siltation alternate in the Yongle Island and Mingyue Island.However,the Jixiang Island is less effected by human activities,but suffers serious erosion,and the residual sand bars has been eroded by 10~30 min 2 years.Surface sediment monitoring in 2016 indicated that the deposits become coarser in winter.Because of the severe erosion of sand beaches in some profiles,the silt basement was exposed,which resulted in the fining of sediments.