厦门湾悬沙分布的多时相遥感分析

利用厦门湾地区多时相遥感图像反演出表层悬沙浓度分布图,进而定性分析不同径流和潮流下悬沙分布规律。研究表明,九龙江河口湾为该地区悬沙浓度最高的区域,分布上具有"西高东低"的特征。全湾悬沙来源主要为两部分:径流来沙以及波浪和潮流掀沙。潮流运动是泥沙输送的主要动力,由于弗劳德数分布不同而引起的潮流挟沙力空间差异,是影响厦门湾悬沙分布的主导因素。利用实测泥沙资料将不同时相下瞬时悬沙浓度转换为全潮平均悬沙浓度以进行定量分析,结果表明悬沙浓度具有大潮大于小潮,枯季大于洪季的特征。

Multi-temporal analyses of remote sensing on distribution of suspended sediment in Xiamen Estuary

The qualitative analysis of suspended sediment distribution law in different runoff and tide is presented from the distribution graphs of suspended sediment concentration which are inversed from multi-temporal remote sensing images of Xiamen Estuary.The research indicates that the concentration of suspended sediment in Jiulongjiang Estuary is the highest in this region,and has the characteristics of higher in the west and lower in the east.The suspended sediment in this region originates mainly from runoff load and wave or tide lift.The tide movement is the main power of sediment transportation.The spatial difference of sediment-laden capacity of tidal flow due to the Froude number distribution is the principal influential factor to distribution of suspended sediment in Xiamen Estuary.According to the practical sediment data,the instantaneous concentration can be converted to the average concentration for quantitative analysis.The results show that the suspended sediment concentration is higher in spring tide and at dry season than in neap tide and at flood season.