Effects of surface inoculation of biological soil crusts on laminar overland flow resistance

Notwithstanding the recognized influence of Biological Soil Crusts (BSCs) on surface roughness and its implication for hydrological processes, limited information is currently available on the effect of BSCs on overland flow resistance. The objective of this paper was to investigate the applicability of a theoretically deduced flow resistance equation, based on a power-velocity profile, using the experimental data set by Jafarpoor et al. (2022) and Sadeghi et al. (2023) for bare soil, which is a control condition, and three inoculated soils (cyanobacteria, bacteria, cyanobacteria+bacteria). In particular, the available data set was used to calibrate the relationship between the velocity profile parameter Γ and the flow Froude number. The developed analysis allowed for stating that (a) the Darcy-Weisbach friction factor can be accurately estimated using the proposed theoretical approach, and (b) the available measurements do not allow for detecting a trend with the soil treatment.