A multifactorial study of mass movement in the hilly and gully Loess Plateau based on intensive field surveys and remote sensing techniques

Lu Yan; Xiao Bai; Pengfei Li; Li Chen; Jinfei Hu; Dou Li; Xin Yang; Lifeng Liu; Jianjian Gao; Tianmin Dang

doi:10.1016/j.scitotenv.2024.171628

A multifactorial study of mass movement in the hilly and gully Loess Plateau based on intensive field surveys and remote sensing techniques

Sci Total Environ. 2024 May 10:924:171628. doi: 10.1016/j.scitotenv.2024.171628. Epub 2024 Mar 11.

Authors

Lu Yan¹, Xiao Bai¹, Pengfei Li², Li Chen³, Jinfei Hu¹, Dou Li¹, Xin Yang¹, Lifeng Liu⁴, Jianjian Gao⁴, Tianmin Dang⁵

Affiliations

¹ College of Geomatics, Xi'an University of Science and Technology, Xi'an 710054, China.
² College of Geomatics, Xi'an University of Science and Technology, Xi'an 710054, China. Electronic address: pengfeili@xust.edu.cn.
³ School of Hydrology and Water Resources, Nanjing University of Information Science and Technology, Nanjing 210044, China.
⁴ Suide Test Station of Soil and Water Conservation, Yellow River Conservancy Committee of Ministry of Water Resources, Yulin 719000, China.
⁵ Yellow River Basin Monitoring Centre of Water-Soil Conservation and Eco-Environment, Xi'an 712100, China.

PMID: 38467256
DOI: 10.1016/j.scitotenv.2024.171628

Abstract

Mass movements, driven by various non-linearly correlated factors, exhibit high randomness, posing vast difficulties for field observations and subsequent investigations into the underlying mechanisms. In this study 157 mass movement incidents (including collapses, slump and spalling) and their primary influencing factors were surveyed in a small catchment of the hilly and gully Loess Plateau, China, through intensive field investigations and remote sensing techniques. The spatial pattern of mass movement and its relation with the influencing factors were assessed, while the relative impact of different factors was studied using the canonical correlation analysis. Results showed that 1) Mass movements predominantly occurred on gully slopes steeper than 70°. Collapses were the main type of mass movement, accounting for 87.9 % of the number of samples. 2) With regard to the impact of individual factors, rainstorms (rainfall intensity >50 mm day^-1) significantly enhanced the occurrence frequency, erosion area and erosion volume of mass movement. The occurrence frequency and erosion area / volume were highest at a soil dry bulk density of 1.34 g cm^-3 and 1.54 g cm^-3, respectively. Mass movement occurred most frequently on unvegetated or unrooted gully slopes, where the resisting effect of vegetation on mass movement was absent. Gully slopes with smooth rather than rugged profiles were also found to be typical areas of mass movement. The occurrence frequency of mass movement decreased with the elevated topographic wetness index (TWI) and distance to slope top and increased with the distance to channels. 3) For the relative impact of different factors, rainfall and shear strength were key factors facilitating and resisting the onset of mass movement, respectively, while topography exerted the greatest influence on the erosion area and volume. This study revealed the relative influence of different factors on occurrence and scale of mass movement, providing a useful reference for modelling and control of the problem.

Keywords: Driving mechanisms; Influencing factor; Remote sensing; Soil erosion; Spatiotemporal pattern.