Granular field of soils in vegetated slopes

Keywords: granular field; GSD parameters of soil; spatial variability
Session Type: Virtual Paper Abstract
Day: Saturday
Session Start / End Time: 2/26/2022 08:00 AM (Eastern Time (US & Canada)) - 2/26/2022 09:20 AM (Eastern Time (US & Canada))
Room: Virtual 12

Abstract

Jun Zhang

Key Laboratory for Mountain Hazards and Earth Surface Processes, Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, China
University of Chinese Academy of Sciences, Beijing 100049, China

Soils in vegetation-covered areas are of high spatiotemporal variability influenced by root growth, and the variability is crucial for soil properties over large scale. Conventionally the spatial heterogeneity is reflected by soil properties and their variance, while the granular textures in terms of graphic parameters are not in use. The present study use the parameters, an exponent μ and a characteristic size Dc, of unified scaling function of the grain size distribution (GSD) to describe soils as a parameter granular field at different scales. We take several study areas of vegetated soils in southwest China, explore the granular field patterns in soils of different root zones and in test spots covered by different vegetation types. The soils present high and low concentration areas of μ, implying high and low concentration of fine grains, with high and low proportions depending on roots. Moreover, the μ values in root zones and spots are subjected to the Weibull distribution of probability, based on which we build the parameter field for two typical vegetated slopes at large scale, assigning μ value for every grid cell of the slope. Then the GSD parameter of soil is embodied in the GIS data and can be analyzed as an elementary attribute of slope.