## 4 Discussion  
The thermic pattern during the two years of study was quite similar and in line with the average of the site while year 2015 was less rainy than 2016 (Figure 1). The similar chemical-physical conditions of the soil recorded at the beginning of the trial suggested that the starting point for the four treatments was the same (Table 1). At the end of 2016, the different floor and water managements affected the soil chemical features (Table 1). S, subjected to water restriction and tillage, showed a decrease in TOC and assimilable P. As observed in other studies, under semi-arid conditions the high temperature and evapo-transpirative demand of the environment, jointly with the low soil moisture lasting for long time during the year, may have increased the mineralization processes, reducing the already low organic carbon in the soil [10; 42; 43]. An additional, related consequence could have been the reduction in P in its assimilable form in the tilted treatment subjected to water shortage [44]. A decrease in P in its assimilable form was observed in an evergreen forest, in the Mediterranean area, subjected to drought stress [45]. M, experiencing the same water supply of S, did not show a decrease in TOC suggesting the positive role of artificial, reflective mulching in preventing organic matter over degradation (Table 1). The use of organic mulching (F) did not affect TOC, while it was not possible to verify if the increase in P occurring in this treatment was given by the floor management per se or to the increased amount of P supplied as fertilizer to feed the service crop (Table 1). Artificial reflective mulching reduced soil evaporation behaving as a physical barrier against the water loss but also reducing solar radiation absorption by the soil and the wind speed at the surface [46]. Even when receiving about 50% less water than the control (T), M maintained SWC higher than T for most of the irrigation season in both years (Figure 3). These preliminary results confirmed what was observed in other studies on rain-fed peach orchards where mulching with plastic film reduced water loss of about 15% in comparison withtilled soil [14]. The flattening technique (F) ameliorated SWC conditions in the rainier year (2016) till the end of July. Afterward, its SWC dropped faster than T after irrigation, in both the years (Figure 3). This rapid water depletion might have been attributable to the disruption of the natural mulching and to the onset of relevant soil cracking occurring in clay soils, low in organic matter [47]. August was characterized by a general water limitation caused by watershed restriction usually occurring in this area (water demand for crop and for civil use increases in this period). Under this stressful condition, M continued to maintain SWC higher than the remaining treatments (Figure 3); only in a few cases its soil water content dropped below the IT, assuring an adequate soil moisture for all the season long [13; 15]. When the soil evaporation was not contrasted, the reduction in water supply (S), produced a progressive consumption of the readily available water with values of SWC very low and below the IT (Figure 3). Soil and water management strategies affected leaf functionality and water relations in peach trees. In both the years, when water supply was not yet differentiated among the four treatments and SWC was within the readily available water range (Figure 3), T, M, F and S behaved similarly (Figures 4 and 5) for carbon assimilation (\(\Sigma\)Pn), water transpiration (\(\Sigma\)Tr) and plant water status, expressed as water