调查潮滩的演化对海岸保护和开发非常重要.随着人为活动的增强,即使过去认为稳定的潮滩也在发生着显著变化.利用航空激光测高( LID AR ) 数据和实测剖面数据对黄河三角洲北部潮滩的地形特征和变化进行了分析.这段海岸的西段海岸平直,潮滩坡降小于1/1000 , 不发育潮沟,潮间有人工开挖的沟道.海岸的东段为老黄河刁口流路岸段.老黄河口岸段突出海岸,同时在两侧形成2 个小海湾.LIDA1R数据揭示了本段潮滩的三维地形和剖面特征.老黄河口突出岸段西北侧潮滩剖面为平直斜坡,坡度1/1000 .而其东侧小海湾湾底的剖面呈上凸的形态,该特征与平面的地形分布、潮间茂密的盐地碱蓬一起,指示淤积.再向东在大堤围成的岬湾内,潮滩受波浪作用形成潮间项.因此,黄河三角洲北部潮滩受局部地形影响大,局部岸段呈侵蚀状态或淤积状态.LIDA1R数据还揭示了潮沟的特征.顺着潮沟的走向,沟底的坡度比潮间带的坡度小,近乎水平,说明涨潮时为何潮沟水位会迅速上升.
Tidal flat of the north Yellow River Delta has been strongly influenced by human activities. In this study, the LIDAR (Light Detection and Ranging) data and in-situ topographic data were used to study the characteristics and changes of the tidal flat in this area. The west section of the area is characterized by straight, featureless tidal flat with tidal slope less than 1/1000. The east sec-tion is the coast of the abandoned Yellow River section. LIDAR data show the topographic characteristics of the tidal flat. In the northwest of the abandoned Yellow River section, the tidal flat profiles are straight slope with a gradient of about 1/1000. However, a tidal profile in the bay in the east of the abandoned river mouth exhibits upward convex. The profile, along with the plan view of topography and the growing saline seepweed (Suaeda salsa), indicates that the tidal flat is accretional. A strong eroded tidal profile is lo-cated in a small bay formed by seawalls. The different patter^is of profiles show that the local factors such as local morphology, hydro-dynamic conditions, and human activities influence the topography of tidal flats. LIDAR data also show that the bottom of a tidal channel is almost flat. Therefore, through the tidal channels, the sea water rapidly enters the tidal flat when the tide comes in.