Olive Pomace Compost in Organic Emmer Crop: Yield, Soil Properties, and Heavy Metals’ Fate in Plant and Soil

Abstract

The effects of olive pomace (OP) compost application on yield and quality of organic emmer, on soil characteristics, and on heavy metals accumulation in plant and soil have been evaluated. The research was carried out in Mediterranean environment for four consecutive years comparing the application of OP compost in two doses and with the addition of a bio-activator. These fertilizing treatments were compared to a commercial organic amendment and an unfertilized control. The application of OP compost ensured both a comparable level of yield than the commercial fertilizer and a high content of protein in the grain, suggesting that it could be an interesting strategy of fertilization for organic emmer. No remarkable heavy metals’ accumulation was found in the plant and soil. Low transfer coefficients and soil accumulation were recorded at the end of experiment, indicating that OP compost could be used as suitable soil amendment, ensuring at the same time an eco-friendly recycling of waste materials. It can optimize organic emmer yield production, sustain soil fertility, and reduce pollution risks linked to the landfill disposal. These results are interesting to develop nitrogen fertilizer strategies for emmer crop, which is an underutilized ancient cereal that well fits for organic production.