Premium
Effect of Particle Surface Roughness on Mechanical Impedance of Coarse‐Textured Soil Materials
Author(s) -
Cruse R. M.,
Cassel D. K.,
Stitt R. E.,
Averette F. G.
Publication year - 1981
Publication title -
soil science society of america journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.836
H-Index - 168
eISSN - 1435-0661
pISSN - 0361-5995
DOI - 10.2136/sssaj1981.03615995004500060040x
Subject(s) - penetrometer , surface roughness , soil water , tillage , bulk density , angle of repose , soil texture , particle (ecology) , surface finish , soil science , materials science , particle size , soil structure , environmental science , mineralogy , geology , composite material , agronomy , paleontology , oceanography , biology
Packing energy required to increase bulk density in coarse‐textured soils is influenced by particle surface roughness, i.e., by interparticle friction. It was, therefore, hypothesized that particle surface roughness would influence soil resistance to movement of a cone penetrometer, because soil bulk density is increased in the zone surrounding the penetrometer tip during its advance. The cone index (C.I.) was calculated for all penetrometer measurements, and C.I. was compared in both disturbed and undisturbed coarse‐textured soil material, with each soil having a unique particle surface roughness as determined by the dense soil angle of repose measurement. For soil materials with similar particle size distributions and bulk densities, C.I. increased as particle surface roughness increased. The role of particle surface roughness in tillage pan formation and in root growth restriction is discussed. It is suggested that, due to poorer aeration during rainy periods and higher mechanical resistance during drier conditions, tillage pans formed in soil materials having smoother‐surfaced particles will be more restrictive to root growth compared to those pans formed in soil materials having rougher‐surfaced particles. Consequently, among soils having root‐restricting tillage pans, the greater enhancement of rooting depth due to subsoiling would likely occur on soils with smooth particles compared to soils with rough soil particles.