Variability of topsoil hydraulic conductivity along the hillslope transects delineated in four areas strongly affected by soil erosion

Soil hydraulic conductivities of topsoils were studied at 5 points of the hillslope transects delineated at 4 geomorphologically diverse areas, where the original soil types (Chernozem, Luvisol and two Cambisols) were due to erosion transformed into different soil unites. Hydraulic conductivities of saturated soils and for a pressure head of –2 cm were measured directly in the field using a Guelph permeameter (K s,GP ) and mini disk tension infiltrometer (K h=– 2 ,MDI ), and in the laboratory using a multistep outflow method (K s,MSO , K h= – 2 ,MSO ). While K s,GP ≈ K s,MSO in the Chernozem and Cambisol (sandy loam) regions, and K s,GP < K s,MSO in the Luvisol and Cambisol (loam) regions. The K s values obtained using different methods showed different trends along the hillslope transects. The K h= – 2 values obtained using different methods showed similar trends along the transects in the Chernozem and Luvisol regions. These trends could be explained by the position within the transects (i.e., different stages of erosion/accumulation processes). No relationships were found between the K h=– 2 values in the Cambisol regions. The pressure head at an inflection point of the a soil-water retention curve was the main parameter, which appeared to associate (negative correlation) with K h=– 2 and K s,MSO in the Chernozem and Luvisol regions.

The impact of the permanent grass cover or conventional tillage on hydraulic properties of Haplic Cambisol developed on paragneiss substrate

This study is focused on the comparison of soil structure and soil hydraulic properties of a Haplic Cambisol on paragneiss under two different land managements. Soil samples were taken from all diagnostic horizons (A, Bw and C) of the soil profile under the permanent grass cover (grassland) and under the conventional tillage (arable land). Basic soil properties were measured. Aggregate stability was assessed using the WSA index. Soil composition was evaluated using micromorphological images. Tension disk infiltrometers with two diameters of 2.22 and 10.25 cm (and applied pressure head of −2 cm) and Guelph permeameter were used to measure unsaturated and saturated hydraulic conductivities, respectively. Soil hydraulic properties were measured in the laboratory using the multistep outflow experiment, which was performed on the undisturbed 100 cm