Impact of compost application rates and depths on soil hydrodynamic properties and irrigation efficiency

Optimal water management in irrigation relies, among other things, on soil properties, which can be modified by agronomic interventions such as composting. It is in this context that the present study was carried out in 2024 at the experimental site of the Institut National de l'Eau to determine the optimal compost dose and burial depth with an effect on soil hydrodynamic properties. A completely randomized experimental block design was used, comprising control plots (without compost) and plots treated with three doses of compost (T1 = 3 kg m −2 , T2 = 4 kg m −2 , T3 = 5 kg m −2 ), each incorporated at three depths (10, 20 and 30 cm). Statistical analyses were carried out using R.4.4.1 software. Results showed that the application of 5 kg compost at 10 cm (T3 P10) improved water retention (0.466 vs. 0.210 cm 3 cm −3 for the control), improved hydraulic conductivity (52.62 cm h −1 vs. 30.35 cm h −1 ) and reduced bulk density (1.06 g cm −3 vs. 1.88 g cm −3 for the control). In conclusion, burying compost at a depth of 10 cm, particularly at a rate of 5 kg m −2 , optimizes soil hydrodynamic properties, contributing to more efficient water management during irrigation under natural conditions for a sandy-loam soil type.