Zhang Bin, Fan ZeMeng, Du ZhengPing, Zheng JiLin, Luo Jun, Wang NaNa, Wang Qing
State Key Laboratory of Resources and Environmental Information System, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China.
Sichuan Provincial Engineering Laboratory of Monitoring and Controlling for Soil Erosion on Dry Valleys, China West Normal University, Nanchong, Sichuan, 637009, China.
Sci Rep. 2020 Jun 29;10(1):10532. doi: 10.1038/s41598-020-66993-9.
Characterizing geomorphological patterns based on digital elevation models (DEMs) has become a basic focus of current geomorphology. A new DEM upscaling method based on the high-accuracy surface modelling method (HASM-US method) has been developed to improve the accuracy of current models and the subjectivity of macroscopic geomorphological patterns. The topographic variables of elevation (EL), slope (SL), aspect (AS), relief amplitude (RA), surface incision (SI), surface roughness (SR), and profile curvature (PC) with a spatial resolution of 1 km × 1 km in the Beijing-Tianjin-Hebei (BTH) area of China have been obtained by using the HASM-US method combined with the principal component analysis (PCA) method in terms of the elevation data of the SRTM-4 DEM, meteorological station location information, and field measurements with a GPS receiver. A geomorphological regionalization pattern has been developed to quantitatively classify the geomorphological types in the BTH area by combining the seven topographic factors of EL, SL, AS, RA, SI, SR, and PC that have significant spatial variation. The results show that the upscaling accuracy of elevation (mean difference only -2.32 m) with the HASM-US method is higher than that with the bilinear interpolation method and nearest neighbour interpolation method. The geomorphologic distribution in the BTH area includes 11 types: low plain, low tableland, low hill, low basin, middle plain, middle hill, low mountain with low RA values, low mountain with medium RA values, middle mountain with low RA values, middle mountain with medium RA values, and middle mountain with high RA values. The low plain is the dominant geomorphological type that covers 40.58% of the whole BTH area. The geomorphological distribution shows the different significant characteristics: the elevation rapidly decreases from the Taihang Mountains to the eastern area, gradually decreases from the Yanshan Mountains to the southern area, and first increases and then decreases from the Bashang Plateau to the southeastern area in the whole BTH area.
基于数字高程模型（DEM）表征地貌格局已成为当前地貌学的一个基本研究重点。为提高现有模型的精度以及宏观地貌格局的客观性，已开发出一种基于高精度表面建模方法的新DEM尺度上推方法（HASM-US方法）。利用HASM-US方法结合主成分分析（PCA）方法，依据SRTM-4 DEM的高程数据、气象站位置信息以及GPS接收机的野外测量数据，获取了中国京津冀（BTH）地区空间分辨率为1 km×1 km的高程（EL）、坡度（SL）、坡向（AS）、起伏度（RA）、地表切割度（SI）、地表粗糙度（SR）和剖面曲率（PC）等地形变量。通过结合具有显著空间变异的EL、SL、AS、RA、SI、SR和PC这七个地形因子，构建了一种地貌区划模式，对BTH地区的地貌类型进行定量分类。结果表明，HASM-US方法的高程尺度上推精度（平均差值仅为-2.32 m）高于双线性插值法和最近邻插值法。BTH地区的地貌分布包括11种类型：低平原、低台地、低丘陵、低盆地、中平原、中丘陵、低起伏度的低山、中等起伏度的低山、低起伏度的中山、中等起伏度的中山以及高起伏度的中山。低平原是主要的地貌类型，占整个BTH地区面积的40.58%。在整个BTH地区，地貌分布呈现出不同的显著特征：从太行山到东部地区高程迅速降低，从燕山到南部地区逐渐降低，从坝上高原到东南部地区先升高后降低。
