Aggregation of undisturbed soil mesoscoms inoculated by earthworm after different cultivation–tillage systems

Earthworms through their feeding, casting, and burrowing activity can have significant influence on a wide range of soil physical properties. A research was conducted in order to study the role of earthworms in modifying the properties of tilled and cultivated soil. Undisturbed soil mesoscoms (500 mm i.d. × 250 mm height) with and without tillage and cultivation, with and without earthwormʹs inoculation were tested and physical properties were compared with existing properties in native field. Earthworms (Allolobophora caliginosa) were inoculated directly in mesoscoms and represented the following treatments: non-cultivated non-tilled (C0T0), cultivated non-tilled (CT0), non-cultivated tilled (C0T) and cultivated tilled (CT). Inoculated soils were incubated for six weeks at 21 ± 1 °C. Inoculated soils reflected significantly higher aggregate meanweight diameter (MWD = 2.75 mm), higher clod density (CD = 1.66 Mg m−3), higher modulus of rupture (MR = 410 kPa), and lower hydraulic conductivity (HC = 0.85 cm h−1) compared with non-inculcated soils. The MWD of inoculated soils for different treatments was in following order: T0C > T0C0 >TC > TC0.