Compost and Biochar As Amendments for Reclaiming a Saline-Sodic Soil Using Recycled Water.

Application of compost and biochar as organic amendments for remediating saline-sodic soils and improving their physical and chemical properties are evaluated in a field study using a Randomized Complete Block experimental design. Treatments include: Biochar, green waste compost and dairy manure compost applied at 50 and 100 Mg ha^-1 and incorporated into the soil. These treatments were evaluated in comparison with traditionally used gypsum, applied at 100% gypsum requirement. Soil samples from 0-15 cm and 15-30 cm depths were periodically analyzed for EC_e, ESP, SAR, aggregate stability and exchangeable cations. Also in-situ unsaturated hydraulic conductivity measurements were made on undisturbed soils using mini disk infiltrometers maintained at 2 cm suction representing the corresponding soil tension. Recycled water from Eastern Municipal Water District, CA was used as a source of irrigation and leaching water. Inorganic nitrogen measurements were also made in order to test the mineralization and nutrient leaching potential of the organic amendments. Preliminary data with respect to soil physical and chemical properties will be presented. Successful remediation provided by these organic amendments in conjunction with the use of recycled water could mitigate the costs associated with the use of expensive inorganic amendments like gypsum and also serve as an environmentally more sustainable option while simultaneously conserving scarce fresh water resources.