苏北废黄河三角洲海岸时空演变遥感分析

Remote Sensing Analysis of Spatial and Temporal Changes of the Coastal Area in the Abandoned Huanghe River Delta in the Northern Jiangsu Province

基于遥感与地理信息系统技术,使用苏北废黄河三角洲海岸地区1978,1987和2000年的Landsat卫星遥感数据,选取岸线指标与波段,提取岸线信息,生成1978—1987年和1987—2000年海岸土地增减时空变化分布图,建立岸线变化距离及增速衡量指标,定量分析了废黄河三角洲海岸面积变化特征,以及灌河口—中山河口、中山河口—扁担港口和扁担港口—双洋河口以南岸段的时空变化格局与分布特征。研究结果表明,废黄河三角洲海岸的自然侵蚀速率呈减小趋势,但侵蚀作用仍在继续。侵蚀强度以废黄河口地区为中心,向南北两侧逐渐减弱。人工保滩护岸措施在一定程度上影响着自然侵蚀格局。其内部各岸段分别呈现缓蚀、侵蚀和基本侵淤平衡的变化格局。

Based on remote sensing and GIS techniques, coastline information was extracted by selecting coastline indicators and appropriate bands using the Landsat data obtained in the coastal area of the aban- doned Huanghe River Dalta in Northern Jiangsu Province in 1978, 1987 and 2000 respectively. Based on the above information, the spatial and temporal distributions of the coastal land increment and decrement both from 1978 to 1987 and from 1987 to 2000 were plotted; the changing distance and increasing rate of the coastline were determined and the characteristics of the Changes in coastal area of the abandoned Huanghe River Delta was quantitatively analyzed, including the coastal segments south of the Guanhe Riv- er mouth （i. e. from the Guanhe River mouth to the Zhongshan River mouth, from the Zhongshan River mouth to the Biandan Harbor and from the Biandan Harbor to the Shuangyang River mouth）. The results have shown that the natural erosion rate in the coastal area of the abandoned Huanghe River Delta tends to decrease, but the erosion is still going on and shows strong at the abandoned Huanghe River mouth. To the south and the north of the mouth, however, the erosion decreases gradually. The human activities may, to certain extend, play a role in the natural erosion of the coast, but within the study area all the coastal segments show generally a pattern of slow erosion, erosion and dynamical balance between erosion and accretion.