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


P. Proietti, E. Federici, L. Fidati, S. Scargetta, L. Massaccesi, L. Nasini, L. Regni, A. Ricci, G. Cenci, G. Gigliotti
Agronomy and Crop Science / Ecology / Animal Science and Zoology


Automatic aperiodic balance

W. and J. George and Becker Ltd.

Transformation of Picloram in Prosopis ruscifolia and Diplotaxis tenuifolia*


Report of the seminar on land-use policies (HBP/SEM. 18/2)

Economic Commission for Europe, Committee on Housing, Building and Planning

Two-phase low-frequency decade oscillator

Muirhead and Co Ltd.

The Planets

BBC and NOVA Producers


te ct . M go X tto 8 ti 63

Agriculture, Ecosystems and Environment 207 (2015) 51–60

Contents lists available at ScienceDirect

Agriculture, Ecosystem journal homepage: www.eA R T I C L E I N F O

Article history:

Received 16 December 2014

Received in revised form 24 March 2015

Accepted 26 March 2015

Available online xxx


Oil mill waste


Bacterial community


Chemical analysis

Oil yield and quality


A new type of solid oil mill waste (SOMW), produced by latest-generation decanter, and its derived compost were spread on land for three consecutive years in an olive grove to evaluate the soil chemical characteristics, bacterial abundance and community structure, plant growth and production and oil quality. After the third year of the experiment in both treatments, there was no increase in total organic C (TOC) in the upper layer, while a reduction of TOC concentration in the deeper layer was detected.

Moreover, in the upper soil layer, the available P increased in both treated soils compared to control while exchangeable K increased only in SOMW treated soil. In both the treated soils, viable counts of different bacteria showed little or no differences compared with the control. Further, PCR-DGGE analysis of the soil bacterial community indicated the presence of a very high biodiversity that was not affected by the longterm treatment with either SOMW and composted-SOMW. The treated soils with both matrices showed an increase in the vegetative activity and olive yield such as a positive effect on oil quality by increasing phenol content. The overall results indicate that both SOMW and its derived-compost can be positively used as soil amendment, thus, contributing to the reduction in the use of chemical fertilizers. ã 2015 Published by Elsevier B.V. 1. Introduction

Olive oil production worldwide continues to increase and is estimated to be about 3.1 106 ton per year and the major portion of the oil production (about 70%) comes from European Union countries (IOOC, 2012). Olive oil sector generates a large amount of oil mill waste (OMW), both solid, known as pomace, and liquid, known as oil mill wastewater, and other by-products, such as, olive tree pruning residues (prunings). At present, the problem of their disposal is enhanced for the short period, from November to

February, of their production (Niaounakis and Halvadakis, 2006;

Morillo et al., 2009).

The chemical composition of solid oil mill waste (SOMW) is very variable. It depends upon the variety of the olive trees, fruit ripening at harvesting, and above all the processing method that, in particular, strongly influences the water content. The most important characteristics of SOMW are high values of chemical oxygen demand (COD) and biochemical oxygen demand (BOD), low pH, high phenols and potassium content (Rinaldi et al., 2003).

Although several patented techniques exist for SOMW management, they are often too costly for most olive oil producers (Niaounakis and Halvadakis, 2006). Italy is the only olive oil producing country in the world where legislation for disposal of oil mill wastes on soil exists. In particular, the Italian Law 574/96 in force since 1996, allows the spreading of up to 50 or 80 m3ha1 per year of oil mill wastes, generated by discontinuous pressure or continuous centrifugation systems, respectively (Law n. 574/96, 1996).

The soil spreading of SOMW, fresh or after composting process, has received increasing attention in modern sustainable agriculture. Many researchers have showed that these wastes have high fertilizer value when applied to the soil (Felipó, 1996; Sequi, 1996;

Alburquerque et al., 2007; Nasini et al., 2013). In fact, SOMW increases soil organic matter content and the concentration of * Corresponding author at: Department of Agricultural, Food and Environmental

Sciences, University of Perugia, Borgo XX Giugno 74, 06121 Perugia, Italy. Tel.: +39 075 5856252; fax: +39 075 5856255.

E-mail address: agr.nasini@gmail.com (L. Nasini). http://dx.doi.org/10.1016/j.agee.2015.03.028 0167-8809/ã 2015 Published by Elsevier B.V.Effects of amendment with oil mill was soil chemical and microbiological chara europaea L.) productivity

P. Proietti a, E. Federici b, L. Fidati b, S. Scargetta b, L

A. Ricci c, G. Cenci b, G. Gigliotti c aDepartment of Agricultural, Food and Environmental Sciences, University of Perugia, Bor bDepartment of Chemistry, Biology and Biotecnology, University of Perugia, Via Elce di so cDepartment of Civil and Environmental Engineering, University of Perugia, Via G. Duran and its derived-compost on eristics and olive (Olea assaccesi a, L. Nasini a,*, L. Regni a,

X Giugno 74, Perugia, Italy , Perugia, Italy , Perugia, Italy s and Environment l sev ier .com/locate /agee 52 P. Proietti et al. / Agriculture, Ecosystems and Environment 207 (2015) 51–60essential elements for plant growth, as well as, it improves microbial activity and soil structure (Mulinacci et al., 2001; LesageMeessen et al., 2001; Zenjari and Nejmeddine, 2001; Sierra et al., 2001; Rinaldi et al., 2003). Sánchez-Monedero et al. (2008) also studied the potential effect of olive wastes on C sequestration, due to the high lignocellulosic content that makes these wastes to degrade slowly during composting and after soil application.

However, the use of SOMW as organic amendment could determine some problems due to their high organic load and mineral salt content, low pH and the presence of phytotoxic compounds (Canet et al., 2008; Del Buono et al., 2011; Gigliotti et al., 2012).

OMW are also known to have anti-microbial and toxic effects, mainly due to the phenolic fraction (Sampedro et al., 2009), that could impair microbe-mediated soil health. On the other hand, the

SOMW composting involves the rapid succession of specialized bacterial populations, with key roles in the organic matter transformation, and the final establishment of a complex stable microbial community that is added to the soil with the amendment (Federici et al., 2011a).