Agro-Industrial and Urban Compost as an Alternative of Inorganic Fertilizers in Traditional Rainfed Olive Grove under Mediterranean Conditions

A three-year field study was conducted to evaluate the impact of two different agro-industrial byproducts on soil properties, provisioning services, olive quality and production in a traditional rainfed grove assess suitable management options for recycling organic wastes reduce use inorganic fertilizers. The amendments consisted compost (AC), made from residues oil industry (“alperujo”), biosolid (BC), constituted wastewater sludge green waste parks gardens. addition enhanced carbon storage, available phosphorous potassium content overtime, whereas no effect detected hydraulics, yield trees growth, partly due high variability encountered among plots. Beneficial effects, especially were more evident during fourth sampling, where increased by almost 40% BC, suggesting that effects need be evaluated long term. Strong seasonal changes most physico-chemical parameters detected, therefore could have been masked. Establishing non-climatic variation scenario would advisable fully detect effects. Our results suggest potentially viable valuable source fertilization, favoring this way circular economy zero waste.