元谋干热河谷浅沟测量方法比较与精度评价

为探究不同测量方法获取浅沟数据的精度，本文以元谋干热河谷区浅沟为例，采用RTK、三维激光扫描、近景摄影测量等多种测量方法获取浅沟数据，建立DEM并提取浅沟形态参数，对比近景摄影测量以不同方式获取标记坐标后建立DEM的差异，同时以测针板实测浅沟横剖面为参照，对比分析不同测量方法获取浅沟横剖面的精度。结果表明：RTK获取密度较低的点数据，建立的DEM较粗糙，仅体现沟缘大致走向；近景摄影测量+RTK方法测得的DEM高程整体低于近景摄影测量+全站仪所得DEM高程；利用三维激光扫描仪和近景摄影测量+全站仪两种方法获取数据所提取的浅沟形态参数精度较高；对比浅沟横剖面，横剖面近景摄影测量+全站仪测量所得与实测横剖面重合度较高。因此，利用近景摄影测量+全站仪进行浅沟测量，在精度、效率等方面优势较大。

Comparison of measurement methods and accuracy evaluation of shallow gully in the Yuanmou Dry-Hot valley

In order to explore the accuracy of different measurement methods to obtain shallow gully data, taking the shallow gully in the Dry+Hot valley area of Yuanmou as an example, the shallow gully data is obtained by various measurement methods such as RTK, 3D laser scanning, close-range photogrammetry and other measurement methods, DEM is established and the morphological parameters of the shallow gully are extracted, and the difference between the DEM is established after the close-range photogrammetry is obtained in different ways after obtaining the marker coordinates, and the accuracy of the shallow gully cross section is obtained by comparing and analyzing different measurement methods. The results show that the DEM established by RTK with low density point data is coarser and only reflects the general trend of the gully margin. The DEM elevation measured by the close-range photogrammetry RTK method is lower than the DEM elevation obtained by the close-range photogram total station. The shallow gully morphological parameters extracted by the 3D laser scanner and the close-range photogrammetry total station are more accurate. The cross-section close-range photogrammetry total station measurement and the measured cross section coincidence is higher compared with the shallow gully cross section. The analysis shows that the close-range photogrammetry total station method, as a shallow gully measurement method, has great advantages in terms of accuracy and efficiency.