基于水动力模型及遥感水边线方法的潮滩高程反演  

DEM RECONSTRUCTION BASED ON HYDRODYNAMIC MODEL AND WATERLINE METHOD

作　　者：郑宗生[1] 周云轩[1] 刘志国[1] 田波[1] 

机构地区：[1]华东师范大学河口海岸学国家重点实验室,上海200062

出　　处：《长江流域资源与环境》2008年第5期756-760,共5页Resources and Environment in the Yangtze Basin

基　　金：国家973项目"长江口及其邻近海域细颗粒泥沙沉积动力过程"(973-2002CB412403)项目;上海市科委科技攻关项目"上海市滩涂资源可持续利用研究"(04DZ12049)资助

摘　　要：由于潮滩范围广，变化频繁，缺乏常规的地形测量资料，给潮滩开发建设带来极大不便。以崇明东滩为实验区，依据长江口1999～2004年多时相遥感影像的光谱特征，对不同潮情的影像采用不同的波段提取水边线信息。同时利用水动力模型软件（Delft3D）模拟卫星过境时刻潮位并赋值给相应的水边线，对具有高程信息的水边线利用地理信息系统空间分析功能进行空间插值处理，生成潮滩的数字高程模型。将初始高程作为模型输入重新运行水动力模型，并将水边线模拟结果与卫星影像提取的水边线对比进一步修正潮滩地形，直到提取水边线与模拟水边线满足精度要求为止。最后利用崇明东滩2005年4条实测剖面与对应年份高程模拟结果进行对比检验。结果表明，该方法能够较高精度地反演潮滩的地形信息，其平均误差分别达到0．50m（σ^2=0.31）、0．19m（σ^2=0.04）、0．15m（σ^2=0.03）及0.13m（σ^2=0.03）。The exploration and development of tidal flat is restricted by the wide range and frqguent variaton of tidal flat and lack of temrain data. In this article,taking Chongming Dongtan as an experiment area,waterlines were extracted from different bands according to tidal conditions on the analysis of spectrum characteristics of multi-temporal remote sensing images （1999 - 2004）. The assignment of an elevation to the waterlines was performed according to two elevation survey profiles. The waterlines labeling elevation were used to construct TINs （Triangulated Irregular Networks）. Then an interpolation for each grid elevation was performed in accordance with the associated triangle. The initial DEM, produced by using model heights generated by running the model with available topography,was then used to refine the topography in the intertidal zone,and the model was re-run to produce improved water levels and a new DEM. This procedure was iterated by comparing models and actual waterlines until no further improvement occurred. Finally,the DEM of Chongming Dontan was examined according to the four transects measured in the year of 2005. The results indicated that the standard deviation of the approach was 0.55 m,0.21 m,0.18 m and 0.16 m,respectively,which eliminated the effects of unavailable tidal height and discrepancy of waterlines on DEM precision.

关 键 词：RS GIS 崇明东滩 数值模拟 冲淤速率 数字高程模型 

分 类 号：P737.1[天文地球—海洋地质] TV147[天文地球—海洋科学]