Estimating the hydraulic conductivity of aggregates conditioned by different tillage treatments from sorption measurements

A procedure is described for obtaining the hydraulic conductivity of the soil of individual aggregates from measurements of the water uptake at negative pressure heads from a small circular porous membrane in contact with the surface of the aggregate. ?The method was validated with measurements on a fine sand that gave results in agreement with those obtained using a constant head permeameter. It was then used to obtain hydraulic conductivity values of aggregates taken from experimental plots under different cultivation treatments. It was found that hydraulic conductivity values of aggregates from field plots that were cultivated by implements hauled by a tractor that compacted the soil, were significantly smaller than those of aggregates from plots that were cultivated by a gantry system that did not compact the soil.