**2.2. Pomace characteristics and treatments**

178 Olive Germplasm – The Olive Cultivation, Table Olive and Olive Oil Industry in Italy

2000; Tomati et al., 1995; Vallini et al., 2001).

*2.1.2. Waste Water effects on the herbaceous crops* 

phenologic stage, the rainfall after the WW supply.

et al., 2007, 2011*a*; Roig et al., 2006).

2007; Vigo et al, 1990).

poliphenols (Della Monica et al., 1978, 1979).

*2.1.3. Waste Water effects on the olive crop* 

to the bioxidative reactions (Benitez et al., 1997; Garcia-Gomez et al., 2003; Paredes et al.,

In this way, on allow on the WW the bioxidative reactions in solid phase, handling to a final product, without phytotoxic effects, useful in the agricultural soils as organic amendment.

The effects of the WW distribution on soils destined to herbaceous crops, vary according to the WW composition, the quantity, the distribution dates in relationship to seeding or crop

The olive mill WW do not generally affect the productivity of the spring-summer crops, when the shedding is effected with an adequate interval time before the seeding. It is also possible to distribute the WW with crop in action, i.e. on autumn-winters cereals, in the full growth phase, limiting the WW doses to not over 40 m3 ha-1 (Bonari et al., 1993; Di Giovacchino & Seghetti, 1990; Di Giovacchino et al., 2001; Marsilio et al., 1990; Montemurro

Negative effects on grass crops are due to the elevated values of electrical conductivity, that can induce salinity damages, flocculation of soil clay fraction, the phytotoxicity of

In the last years, because of environmental protection policy, new technologies that minimize these risks were developed. In this framework, the raw olive waste water was differently treated to improve the percentage of recycle of these materials. In particular, different studies indicate that the application of mineral catalyser (MnOX) on WW reduces the level of poliphenols and other pollutants. As a consequence, this treatment decreases both phytotoxicity and temporary immobilization of soil mineral N, thus making the treated WW able to sustain good levels of crops yield and products quality (Montemurro et al.,

Many experiences have confirmed the possibility to distribute the WW on the olive grove more than over 400 m3 ha-1 without significant variations of vital parameters as the photosynthetic activity, transpiration, stomatic conductance, leaves carbohydrates and chlorophylls content. Conversely, improvements of the productivity on treated plants was frequently observed. A decrease of the vegetative development has been recorded only on

The organic matter content in WW treated soil always results greater in comparison to the

In the soils treated with WW a greater presence of the total microflora was found (Fungi and other microbial groups), as well as an increase of respiratory and enzymatic activities. These findings showed the absence of toxicity of the WW towards the microorganisms, and the

young plants raised in pots and treated with higher WW doses (Proietti et al., 1988).

untreated control, with greater nitrogen contents and more elevated C/N ratio.

The olive pomace is composed of fruit matter (olive skins, flesh, seeds and stone fragments), and of different amount of vegetation and process water which contains the water-soluble constituents of the fruits, in order to the extraction system used.

The OPP and OP3 are usually destined to the pomace industry, for the extraction of residual oil by solvents; and then used as fuel, also in cogenerative processes (Molinari & Bonfà, 2005). These by-products could also be used as animal food, or in biodegradative processes to produce ethanol (Ballesteros et al., 2002), or compost for agricultural utilization. Nevertheless the olive pomace, being constituted by vegetable not fermented organic matter, does not contain heavy metals, toxic pollutants or pathogens, and can be considered as a vegetable amendment (Table 3), (Alburquerque, et al. 2004). Therefore, it can be used in the agricultural soils without any treatment, as allowed by the current normative (Law 574/1996).


**Table 3.** Main characteristics of the olive pomace (dry weight)
