Nanotechnology holds promising potential as an innovative approach for improving the physical and hydraulic properties of saline soils. In this study, a comparative evaluation was conducted on the effects of organic and mineral soil amendments applied at both nano and conventional scales on a loamy saline soil. The experimental treatments included pomegranate peel-derived biochar and nanobiochar, nano-bentonite, zeolite, micro-silica, and nano-silica, which were applied in soil columns (10 cm diameter × 35 cm height) under a completely randomized design with three replications. Results indicated that, before leaching, the highest electrical conductivity (EC = 23.597 dS m⁻¹) and sodium concentration (4903 mg kg⁻¹) were recorded in the pomegranate peel biochar treatment. Conversely, the lowest pre-leaching EC (13.817 dS m⁻¹) was observed in the nano-silica treatment, while nano-bentonite exhibited the lowest sodium concentration (2054 mg kg⁻¹). Analysis of leachate collected after irrigation with four pore volumes of water revealed that nano-bentonite produced the lowest EC and potassium and iron concentrations, whereas nano-silica produced the lowest calcium concentration. In contrast, the pomegranate peel biochar treatment yielded the highest EC and concentrations of calcium, potassium, and iron in the leachate.

These findings demonstrate that nano-engineered amendments particularly nano-bentonite and nano-silica, exhibit significant efficacy in mitigating salinity and modulating the leaching dynamics of key ions (Na⁺, K⁺, Ca²⁺, and Fe²⁺/³⁺), thereby offering viable, sustainable strategies for the reclamation and management of saline soils.