天津港至南排河岸段海域悬沙运动遥感分析

Remote sensing analysis on movement of surface suspended sediment in coastal waters from Tianjin Port to Nanpai river estuary

利用Landsat-5/7卫星影像资料和实测含沙量资料,建立天津港—南排河岸段海域悬沙遥感模式,对表层水体悬沙分布及泥沙运动情况进行分析。研究表明,该海域含沙量均呈现从近岸至外海递减,具有明显的层次性;相对较高的含沙区域主要集中在-2m等深线以内,其表层含沙量一般在0.3kg/m3以上;沿岸线走向,含沙量的大小及分布范围总体呈现自北向南有所增大的特点;悬沙分布受季节性影响较大,冬季大风掀沙使得冬季含沙量明显大于夏季;当海域吹向岸风时近岸的含沙量要比吹顺岸风或离岸风时近岸含沙量高。

According to the Landsat-5/7 remote sensing data and in-situ silt content data acquired quasisynchronously,the quantitative remote sensing model for suspended sediment in the coastal waters from Tianjin Port to Nanpai river estuary was set up.The results show surface suspended silt content reduces gradually from outside sea area to nearshore area.In general,there is high surface suspended sediment concentration with much more 0.3 kg/m3 within the area of -2 m isobaths.From north to south along seacoast,suspended sediment concentration increases gradually.Moreover,the seasonal change of suspended sediment shows that winter concentration is higher than summer by the wind action.It is different by the different directional wind action that the concentration is higher under the shoreward wind than the offshore or direct-shore wind.