Soil erosion, rapid geomorphological change and vegetation degradation are major threats to the human and natural environment. Unmanned Aerial Systems (UAS) can be used as tools to provide detailed and accurate estimations of landscape change. The effect of flight strategy on the accuracy of UAS image data products, typically a digital surface model (DSM) and orthophoto, is unknown. Herein different flying altitudes (126-235 m) and area coverage orientations (N-S and SW-NE) are assessed in a semi-arid and medium-relief area where terraced and abandoned agricultural fields are heavily damaged by piping and gully erosion. The assessment was with respect to cell size, vertical and horizontal accuracy, absolute difference of DSM, and registration of recognizable landscape features. The results show increasing cell size (5-9 cm) with increasing altitude, and differences between elevation values (10-20 cm) for different flight directions. Vertical accuracy ranged 4-7 cm but showed no clear relationship with flight strategy, whilst horizontal error was stable (2-4 cm) for the different orthophotos. In all data sets, geomorphological features such as piping channels, rills and gullies and vegetation patches could be labeled by a technician. Finally, the datasets have been released in a public repository.

中文翻译：

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使用固定翼无人机在穆尔西亚（西班牙）评估洪水高度和掩护方位对数字水面模型（DSM）准确性的影响，以评估洪水危害

土壤侵蚀，快速的地貌变化和植被退化是对人类和自然环境的主要威胁。无人机系统（UAS）可以用作提供详细而准确的景观变化估计的工具。飞行策略对UAS图像数据产品（通常是数字表面模型（DSM）和正射影像）准确性的影响尚不清楚。在半干旱和中等起伏地区，梯田和废弃农田被管道和沟壑侵蚀严重破坏，在此评估了不同的飞行高度（126-235 m）和区域覆盖方向（NS和SW-NE）。评估是关于像元大小，垂直和水平精度，DSM的绝对差异以及可识别的景观特征的配准。结果表明，随着高度的增加，像元大小增加（5-9厘米），并且不同飞行方向的高程值之间也相差10-20厘米。垂直精度范围为4-7厘米，但与飞行策略没有明确的关系，而不同正射照片的水平误差稳定（2-4厘米）。在所有数据集中，技术人员都可以标记管道通道，小溪和沟壑以及植被斑块等地貌特征。最后，数据集已在公共存储库中发布。小溪，沟壑和植被斑块可由技术人员标记。最后，数据集已在公共存储库中发布。小溪，沟壑和植被斑块可由技术人员标记。最后，数据集已在公共存储库中发布。