滦河三角洲典型潟湖-沙坝海岸岸线稳定性评价

The stability evaluation of lagoon-barrier coastline, Luanhe delta

  • 摘要: 滦河三角洲潟湖-沙坝海岸在我国海岸类型中最具特色,具有重要的教学和科研价值,在自然和人类共同作用下,海岸线一直处于动态的演变过程中。选取1987年、2000年和2014年三期遥感影像提取岸线数据,计算近年来潟湖-沙坝海岸岸线纵深度、年均变化速率和稳定性指数,分析各沙坝海岛岸线的稳定性。结果显示滦河三角洲潟湖-沙坝岸线以向陆蚀退为主,最大纵深度变化向陆蚀退近400 m,最大纵深度年均变化速度达-30 m/a,岸线以微侵蚀至严重侵蚀所占比例达到87%,74%海岛稳定性指数小于0.4。这主要是由于滦河中上游修建水库导致入海泥沙量减少,同时港口、养殖池的修建也对岸线稳定性起到负面影响。

     

    Abstract: Luanhe delta has important values in the field of teaching and scientific researches as the most special feature of lagoon-barrier coastline, whose coastline always stays in the state of dynamic changes with the human influence.For calculating the axial length change, annual mean change rate and stability index of coastline for lagoon-barrier in recent years, furthermore, analyzing the stability of sandbar coastline, we extract coastline datum from remote sensing images of 1987, 2000 and 2014.This research reveals that the coastline of lagoon-barrier in Luanhe delta mainly erodes toward land and its maximum axial length is nearly 400 m, whose erosion rate nearly reaches 30 m/a.The ratio of erosion degree from lightly to severe can reach 87%, the stability index of islands that less than 0.4 reaches 74%.After that, more researches have been carried out and indicate that reservoirs construction in the middle and upper reaches of the Luanhe reduce terrestrial sediment supply, which is the main reason that for these changes.Besides, constructions of ports and culture ponds also weaken coastline stability.

     

/

返回文章
返回