Soil Water Retention and Infiltration Under Different Mulching Treatments in Lagos State, South West Nigeria

This study evaluates soil water retention characteristics and infiltration rates under different surface mulching treatments in vegetable production plots in Lagos State, located in Nigeria's South West geopolitical zone. Lagos State's bimodal rainfall and dense urban and peri-urban vegetable farming create critical needs for water conservation techniques that sustain soil moisture between rainfall events and reduce irrigation requirements. A field experiment was conducted using a randomised complete block design with five mulching treatments: no mulch (control), rice straw mulch at 4 tonnes per hectare, dried grass mulch at 4 tonnes per hectare, black polyethylene film mulch, and compost mulch at 4 tonnes per hectare. Plots were maintained over one growing season on a sandy loam soil in Ikorodu local government area. Soil water content at 10, 20, and 30 cm Soil Sciencehs was monitored weekly using a time domain reflectometry probe. Infiltration rates were measured monthly by double-ring infiltrometer. Findings revealed that compost mulch and rice straw mulch produced the greatest improvement in soil water retention, maintaining significantly higher soil moisture at all three Soil Sciencehs compared to bare soil. Infiltration rates under mulched plots were 40 to 65 percent higher than the bare soil control, reducing runoff risk. Black polyethylene film improved water retention but slightly reduced infiltration by directing inter-row water flow. The study recommends compost mulching as the most effective and sustainable mulching strategy for water conservation in Lagos State peri-urban vegetable production. Keywords: mulching, soil water retention, infiltration, Lagos State, vegetable production.