黄河三角洲多年海岸线动态变迁特征及演化规律

以黄河三角洲1976—2014年的MSS、TM、ETM+影像为数据源,采用一般高潮线法提取不同时期的海岸线,结合RS遥感与GIS技术,对黄河三角洲的岸线变化进行监测.结果表明,1976年以来黄河三角洲的岸线形态及长度均发生了较大变化,其中北部的刁口河流路区岸线向内陆蚀退明显,以海洋侵蚀作用为主,属于蚀退型海岸;清水沟流路区的岸线整体向海域推进,海岸处于进淤状态,属于强淤进型海岸.黄河三角洲岸线变化频繁而快速,黄河的入海流路、水沙量、降水量等是影响黄河三角洲岸线变化的重要因素;行水期黄河三角洲岸线一般以淤进造陆为主,停止行河岸段,海岸侵蚀后退速率趋于缓慢,逐渐地变得相对稳定,在长时间不行水的海岸段,岸线基本保持稳定,随着黄河三角洲海岸带人类工程经济活动的加剧,该区域的海岸线演变受人类的影响越来越大.

Characteristics of coastline change and multiyear evolution of the Yellow River Delta

The coastline of the Yellow River Delta (YRD) was monitored based on the coastlines extracted by the general high-tide line method with the techniques of remote sensing and geographic information system and the data source from multi-spectral scanner, thematic mapper, and enhanced thematic mapper + images of the YRD from 1976 to 2014. The results demonstrated that the shape and length of the YRD coastline had changed dramatically since 1976. It shows that the coastline in Diaokou course demonstrates mostly an inland erosion in the north due to primarily a marine erosion and it is an erosion-type estuary. However, the coastline of the Qingshuigou course was pushed seaward demonstrating an accretion stage and thus it is an accretion-type estuary. The YRD coastline changes frequently and rapidly. The mouth channel, the water and sediments, and the precipitation are the major factors affecting the YRD. The YRD coastline is mainly in an accretion stage during the water running period. The erosion rate decreases and tends to be stable on the dry course. The coastline is basically stable when the course had been dried for a long time. The development of the YRD is increasingly affected by human activities in recent years.