基于海图数据的水下岸坡插值精度分析对比研究

A comparative study on interpolation accuracy of underwater slope terrain based on sea chart data

数字高程模型是研究水下岸坡冲淤变化的一种重要手段。不同的插值方法和像元大小都会对数字高程模型的精度产生影响,从而导致冲淤分析结果的变化。本研究使用了六种常用的插值方法(ANUDEM、反距离函数法、克里金法、自然邻域法、样条函数法、不规则三角网转栅格法)对莱州湾和烟台港不同年份和尺度的水深数据进行了插值,计算了均方根预测误差、源数据残差均方根误差、残差均值、残差最大值和残差最小值等精度计算指标。结果表明ANUDEM和自然邻域法的均方根预测误差和源数据残差均方根误差均小于1 m。ANUDEM和自然邻域法对不同尺度的水下岸坡数据插值有着较好的适用性。

Digital Elevation Model(DEM)is an important method for underwater slope erosion-deposition variation research.The interpolation method and pixel size both have effects on the accuracy of DEM,which have great impacts on the conclusion of erosional and depositional variation.Six interpolation methods(ANUDEM,IDW,Kriging,Natural Neighbour,Spline,TIN to Raster)were used for different years and scales water depth data about the Laizhou Bay and Yantai Port.RMSPE,RMS,mean max and min absolute value of residual were calculated using R language.The erosional and depositional volumes of different methods were also calculated.The RMSPE and RMSE values of ANUDEM and Natural Neighbour are both less than 1 meter.The experiment result shows that both ANUDEM and Natural Neighbour methods have good applicability for underwater slope interpolation on different position and multi-resolution conditions.