Analysis of CT-Measured Pore Characteristics of Porous Media Relative to Physical Properties

Abstract

Understanding variability of porous media is important for initiating land management strategies. Objectives were to determine variability of computed tomography (CT)-measured pore characteristics and physical properties of porous media and combine these into principal components (PCs). Core samples were collected from three sites: silvopasture with vegetative buffers (SPBF), watersheds with vegetative buffers (PW), and crop management and prairie management (MP). Soil bulk density (BD), saturated hydraulic conductivity (Ks) and CT-measured pore characteristics were analyzed under buffers and management practices at SPBF; buffer and crop management practices at PW; and native prairie, restored prairie, conservation program, and crop rotation at the MP location. Measured data sets were combined by location for correlation analysis, descriptive statistics, variability analysis, principal component analysis (PCA), and discriminant analysis. Coefficients of variation (CV) showed numbers of pores, macroporosity, mesoporosity and Ks were most variable (CV > 0.35), whereas circularity, BD and silt content were least variable (CV < 0.15). The PCA grouped ten pore characteristics and physical properties into three PCs: porosity, water transport and texture. Redundancy analysis showed the soil porosity PC and pore numbers as the most dominant properties at all locations. Results indicate that establishment of vegetative buffers improves porosity.