Effects of amendment with oil mill waste and its derived-compost on soil chemical and microbiological characteristics and olive (Olea europaea L.) productivity

Long Term Amendment with Fresh and Composted Solid Olive Mill Waste on Olive Grove Affects Carbon Sequestration by Prunings, Fruits, and Soil

“…), as reported in a previous study (Proietti et al, 2015), the direct land spreading on agricultural surfaces appears operationally simple and economically feasible. On the other hand, application of this waste material to the soil may have negative agronomical and environmental implications due to the acidic pH and the high content of potentially phytotoxic and anti-microbial compounds, such as phenols, tannins and fatty acids (Alburquerque et al, 2004).…”

“…Further, the recycling of OMW as soil amendments in the agricultural fields should avoid its disposal in landfills or burning in incineration plants that could bring, in addition, possible environmental concerns. The positive influence of OMW added to soil on the vegetative activity and yield of the olive trees has already been recognized by several authors (e.g., Altieri and Esposito, 2008; Giorgi et al, 2008; López-Piñeiro et al, 2008; Chartzoulakis et al, 2010; Camposeo and Vivaldi, 2011; Nasini et al, 2013; Proietti et al, 2015; Russo et al, 2015). Palese et al (2013) demonstrated the potential of olive trees in sequestering C in an olive grove in Southern Italy, by calculating the biomass of the tree and the respective CO 2 sequestration, and recent studies have shown that the application to soil of OMW-derived composts can improve long term C sequestration by the capacity of olive groves to store C in the tree biomass (Nasini et al, 2013).…”

“…At the end of the thermophilic phase the material was placed in an open container without forced air until the curing phase was completed. The composting process was described in detail in a previous study (Proietti et al, 2015) and the chemical characteristics of SOMW and C-SOMW+P are reported in Table 1.…”

“…Strategies based on changes in land use and agricultural management addressed in increasing the C stored in the tree biomass and into the soils have been reported to be potentially important to reduce atmospheric CO 2 (Jarecki and Lal, 2003; Gómez et al, 2009). Among the agricultural managements, the addition to soil of organic wastes as amendments derived from various sources represents an efficient practice to increase soil organic C content in the agro-ecosystems (Mondini and Sequi, 2008; Sánchez-Monedero et al, 2008; Lozano-García et al, 2011; Bedbabis et al, 2015; Proietti et al, 2015; Russo et al, 2015). Furthermore, this strategy would bring other desirable benefits, such as enhancement of soil structure, increase soil fertility, and decrease soil erosion rate (Sánchez-Monedero et al, 2008).…”

“…These negative aspects can be, however, partly overcome through the composting of OMW (Gigliotti et al, 2012; Nasini et al, 2016). Although, some authors reported the effect of the organic amendment derived from OMW on the olive grove productivity (Nasini et al, 2013; Palese et al, 2013; Proietti et al, 2015), and on soil physical-chemical characteristics (López-Piñeiro et al, 2011) and C sequestration (Sánchez-Monedero et al, 2008), as far as we know, no study has yet compared the impact of different forms of OMW on the productivity and on the capability to store carbon of the olive grove ecosystem. To fill this gap, the aim of the present work was to test the effects, in terms of productivity and C sequestration, of fresh and composted solid olive mill waste added to the soil of an olive grove for a long period.…”