IN SITU APPLICATION OF CLINOPTILOLITE TO IMPROVE COMPOST QUALITY PRODUCED FROM PISTACHIO BIO-WASTES

Pistachio wastes are very rich in organic matter (70-80%) and have C/N ratio suitable for composting. However, due to the extremely high electrical conductivity (EC) of the bio-solids wastes (mainly from the salty water used for pistachio trees irrigation), the final compost presented with high EC, making the final product unable for agricultural proposed. The paper focus on the development of methodology for the treatment of pistachio waste with clinoptilolite. 5% w/w of natural zeolite (clinoptilolite) in the feed-stock mixture improved the quality of the compost. Comparison of the compost properties with the European standards for the safe use and application of composts and other organic materials as soil amendments indicates that the zeolite-compost can be used without any limitation on soil for plant growth or land rehabilitation.