基于遥感和GIS的辽河口拦门沙演变研究

河口拦门沙浅滩冲淤演变对于河口生态环境保护及资源开发利用等具有十分重要的意义。以辽河口拦门沙地带为研究对象，采用遥感和GIS相结合的方法，克服了实测地形资料缺乏的困境，对辽河口拦门沙的冲淤演变特征进行了研究，并探讨了演变的原因机制。研究结果表明：近期辽河口拦门沙外缘整体呈侵蚀后退趋势，这主要与流域来沙减少有关；蛤蜊岗子滩和西滩都有向东淤涨的趋势，这与拦门沙外缘侵蚀的泥沙向上游搬运及局部河势变化产生的泥沙输移有关；辽河干流水道内江心洲不断向下游淤涨，对局部河势及拦门沙浅滩的演变会产生较大的影响。

EVOLUTION OF THE RIVER MOUTH BAR IN LIAOHE ESTUARY WITH RS AND GIS METHODS

Evolutionary history of river mouth bars is of significance to environmental protection and resource development and management in estuaries. The topography of the Liaohe Estuary is complicated by shallow shoals. In this research, RS and GIS technology are adopted to reveal the evolutionary characteristics of river mouth bars. Discussion is also devoted to the driving force of the evolution. Research results show that the outer edges of the sand barriers in the Liaohe Estuary have been under the erosion recently and the shoal line retreated obviously owing to the decrease in sediment supply from upstream. Instead, the eastern edge of the Geligangzi Shoal and West Shoal are under siltation and the shoal line have moved eastward obviously, due to sediment supply from the outer edge of river mouth bars in addition to the sediment coming from the erosion of river shoal and river bed upstream. The central shoals of the main channel of the Liaohe River have continuously remained under deposition and expansion downstream.