Evaluation of Biobed Bio-Mixture from Olive Oil Mill Wastewater Treatment as a Soil Organic Amendment in a Circular Economy Context

This study, based on circular economy principles and sustainable development practices, aims to present the results of soil samples analysis after their mixture with a biobed bio-mixture straw, compost, used for two consecutive years as organic bio-filter olive oil mill wastewater. So far, exhausted bio-mixtures in biobeds minimize pesticide point-source contamination turned out contain residues pesticides, they are considered hazardous wastes; thus, require special treatment before disposal. Contrariwise, saturated from bio-bed systems utilized wastewater (OMWW) not only do any final disposal but also can be exploited amendment. To this end, effects application three different proportions amendment physical chemical properties medium-texture were investigated. The water simulating typical irrigation period during growing season took place. Upon completion application, collected depths columns analyzed, leachates analyzed. Soil texture, matter, calcium carbonate, electrical conductivity (EC), pH, total nitrogen, nitrates, nitrites, ammonium, available phosphorus, exchangeable potassium, sodium, magnesium, sodium percentage (ESP), cation exchange capacity (CEC), iron, manganese, copper, zinc boron monitored indexes potential amendment, EC, calcium, adsorption ratio (SAR), hardness, groundwater contamination.The study demonstrated effective use an while impact selected amendments was minimum.