With the objectives of assessing variations in selected soil properties, two tillage types: agroforestry
based conservation tillage (AFCST) and maize based conventional tillage (MCVT) under three age
categories (5, 10 and 15-years) were selected in Chichu and Haroresa Kebels, Dilla Zuria, Ethiopia. A total
of 48 composite soil samples (4 replication 2 tillage types 3 age categories 2 soil depth layers: 0–
10 cm and 10–20 cm) were collected to analyze texture and soil organic carbon (SOC%). Addational
undisturbed core samples were also collected to determine soil bulk density (g cm3
). Water infiltration
capacity was also measured in the field using double ring infiltrometer. The results showed that clay and
sand textural fractions significantly varied (p < 0.001, p = 0.002, respectively) with age of land
management. Soil bulk density, soil moisture content (SMC), total porosity (Pt) and soil organic carbon
(SOC) varied significantly with tillage types (p < 0.001) and soil depth (p < 0.001). Water infiltration
(rate and cumulative) significantly varied (p < 0.001) with tillage types: higher in the AFCST than in the
MCVT. Lower soil bulk density, higher soil organic carbon (SOC) and soil moisture content (SMC) were
observed in the top 0–10 cm soil layer under the AFCST than in the MCVT. Soil bulk density and soil
moisture content (SMC) increased while total porosity (Pt) and soil organic carbon (SOC) decreased with
soil depth in both tillage types. Improvement in the soil properties under AFCST was due to higher soil
organic matter (SOM) input and less soil disturbance. Thus, reducing the frequency of soil disturbance
through application of conservation tillage would help to improve the soil quality.
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