PROGRESS IN GEOGRAPHY ›› 2021, Vol. 40 ›› Issue (9): 1570-1580.doi: 10.18306/dlkxjz.2021.09.011

• Industrial Applications of UAV • Previous Articles     Next Articles

Modelling sediment transport in space in a watershed based on topographic change detection by UAV survey

DAI Wen1,2,3(), TANG Guo'an1,3,4, HU Guanghui1,3,4, YANG Xin1,3,4, XIONG Liyang1,3,4,*(), WANG Lei5   

  1. 1. School of Geography, Nanjing Normal University, Nanjing ?210023, China
    2. School of Geographical Sciences, Nanjing University of Information Science and Technology, Nanjing 210044, China
    3. Key Laboratory of Virtual Geographic Environment (Nanjing Normal University), Ministry of Education, Nanjing 210023, China
    4. Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing 210023, China
    5. College of Urban and Environmental Sciences, Northwest University, Xi'an 710069, China
  • Received:2020-09-04 Revised:2020-12-08 Online:2021-09-28 Published:2021-11-28
  • Contact: XIONG Liyang;
  • Supported by:
    National Natural Science Foundation of China(41930102);National Natural Science Foundation of China(41971333);National Natural Science Foundation of China(41771415);Priority Academic Program Development of Jiangsu Higher Education Institutions(164320H116)


Sediment transport rate, as an important indicator for studying Earth surface processes and for planning soil and water conservation, is a spatial variable. However, traditional monitoring methods can only obtain the global sediment transport rate in a certain area and are unable to map the spatial distribution of sediment transport rate. In this study, unmanned aerial vehicle (UAV) photogrammetry was used to obtain a two-phase digital elevation model (DEM) and calculate the amount of topographic change. In accordance with the principle of mass conservation and using a multi-flow direction algorithm, a spatial sediment transport model was established, by which the spatial sediment transport rate from a loess watershed was obtained. The results show that this method can effectively simulate the transportation of sediment in space. The area where the mass is not conserved is less than 4%, and the non-conserved areas are mostly those that are affected by human activities. The effects of DEM choice and the level of topographic change detection on the proposed model are also discussed. When DEM in the first phase is used to calculate the sediment transportation path, the area where the mass is not conserved is significantly reduced. The results of the spatial sediment transport model are more robust when a precision map is used to detect topographic changes, whereas the results from topographic changes detected by root mean square error (RMSE) greatly varied under different confidence levels. The proposed model can conveniently and quickly provide a detailed spatial distribution of sediment transport rate through UAV-based topographic change detection, which provides new perspectives for research of Earth surface processes.

Key words: UAV photogrammetry, soil erosion monitoring in a watershed, topographic change detection, spatial distribution of sediment transport rate, precision map, sediment transport