在中国区域内随机选取的78个实验区域的DEM数据作为实验对象,分别进行系列分析区域尺度的地形起伏度计算,建立了基于微观地形特征因子的地形起伏度最佳分析区域预测模型。实验结果表明:相同区域、不同尺度的DEM数据提取的地形起伏度存在差异,DEM尺度相差较小时,地形起伏度的差异也较小;地形起伏度和实验区域的平均高程、区域高程差、平均坡度和平均坡度变化率等地形特征因子存在强相关关系;当置信水平为0.05时,预测模型拟合参数的准确率达到95%以上,证明预测模型可以有效地确定最佳分析区域的取值范围。

In this paper, we uses Digital Elevation Model(DEM) with three different scales in 78 study areas to calculate multi-scale relief, and tries to ascertain the evaluation model of relief and to calculate the optimum statistical unit. The experiment result shows that the relief of the same experimental area with different scale exists a certain extent of difference, the smaller difference of the scale, the smaller difference of the relief. There is a strong relationship between the relief and the terrain factors of the experimental area such as the average elevation, the elevation difference, the average slope and the average slope variability. Based on this, we build the prediction model of the relief. We use the prediction model to estimate the scale of optimum statistical unit and the accuracy of the prediction model to fitted parameter is above 95%. The experimental results show that the model can effectively determine the optimum statistical unit of relief.