Runoff, soil erosion, and crop responses to Palash (Butea monosperma) leaf mulching in semi-arid vegetable production

In semi-arid regions, soil erosion and nutrient losses present significant challenges to the sustainability of vegetable farming, as the scarcity of residues limits the adoption of mulching practices. Most crop leftovers are used for animal feed or fuel, which results in limited mulch availability. We evaluate Palash ( Butea monosperma ) leaf biomass as a mulching material to study crop root-shoot characteristics with hydrological responses, including erosion, nutrient loss, soil properties, and yield in pumpkin ( Cucurbita moschata ), okra ( Abelmoschus esculentus ), amaranthus ( Amaranthus spp. ), and brinjal ( Solanum melongena ) with mulch (WM) and without mulch (WoM) conditions. Results showed that Palash mulching reduced runoff and soil loss across crops. In brinjal, surface runoff decreased from 66.43 mm (WoM) to 20.88 mm (WM) in 2022 and 154.40 mm to 46.26 mm in 2023, while soil loss declined from 2.44 to 0.25 t ha -1 in 2022 and 7.10 to 0.71 t ha -1 in 2023. Okra WM showed lowest nutrient losses (sum of OC, N, P, K) of 3.79 kg ha -1 in 2022 and 8.47 kg ha -1 in 2023, versus highest losses of 17.47 kg ha -1 and 41.19 kg ha -1 under brinjal WoM. Mulch improved soil moisture by 9-36%. Soil properties improved with mulching, showing lower bulk density (1.67–1.70 vs. 1.70–1.78 g cm -3 ), higher aggregate stability (70.98–73.25% vs. 66.93–69.99%), greater hydraulic conductivity (10.58–11.27 vs. 6.36–7.05 cm hr -1 ), and higher soil organic carbon (0.48–0.58% vs. 0.38–0.42%). Mulching increased crop yields by 2.2% for amaranthus and 40% for pumpkin. Overall, the results indicate that Palash leaf mulching is an effective practice that reduces soil erosion, conserves soil moisture, and improves crop productivity in semi-arid vegetable production systems. • Palash ( Butea monosperma ) mulch as a Nature-based Solution reduced runoff (49–69%) and soil loss (68–90%) across vegetable systems. • Mulching minimized nutrient losses by 53–73%, enhancing key ecosystem services. • Improved canopy cover and root traits under mulch strengthened soil properties in support of Land Degradation Neutrality targets. • Palash mulch increased soil moisture by 9–36%, boosting soil moisture conservation and crop productivity.