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A three year experiment was carried out to test the possibility of using the carbon isotope ratio ( δ 13 C) measured in wine, combined with data of proximal and remote soil sensors, to assess viticultural and oenological suitability for Sangiovese. Two specialized vineyards on similar geomorphological conditions were investigated. Twelve plots were positioned differently along slopes. The soils were similar, except for structure, porosity and related hydrological characteristics, and salinity of the deeper horizons. Soil electrical conductivity and resistivity were measured at three different depths, as well as cumulative soil moisture down to the root-limiting layer. Satellite images were analyzed to obtain the NDVI. Soil water content in the plots was monitored at different depths. Yield, phenological phases, and chemical analysis of grapes were determined. Stem water potential was measured during summer. Grapes of each plot were collected for wine making in small barrels. The wines obtained were analyzed and submitted to a blind organoleptic testing. The wine was also analyzed for its δ 13 C isotopic ratio. Almost all plots had rather high amounts of transpirable water, even during the driest time of the year. However, only yield components of Sangiovese were influenced by water availability. Wine quality was instead significantly improved by the moderate salinity of the deeper horizons, which increased plant water stress during berry ripening and reduced production. The moderate physiological stress affecting vines was reflected in stem water potentials and δ 13 C values. δ 13 C was correlated with several viticultural and oenological parameters, and also with panel test evaluations of wine quality. The threshold between good and bad scores corresponded to a δ 13 C value of −26.7 ± 1.2‰. Soil salinity affected the geophysical survey and its relationship with the viticultural and oenological result. In particular, the electromagnetic conductivity measured at the beginning of the experiment was functional in distinguishing the two vineyards, but it was not useful for a more detailed prediction of Sangiovese performance. However, electromagnetic resistivity in the first 0.5 m was not influenced by salinity of the deep soil horizons, but only by clay content, and permitted a significant estimation of the Sangiovese anthocyanins content, colour intensity, and must acidity. The outcomes of this study recommend the use of δ 13 C in combination with electromagnetic resistivity to map soil suitability for Sangiovese. The favourable performance of Sangiovese in moderately saline soils may encourage diffusion of the cultivar outside its traditional areas of cultivation.

This study aimed at setting up a comprehensive approach on viticultural and olive tree cultivation environmental impact, through soil and landscape change analysis at the years 1965, 1990, 1994 and 2000, both at the catchment and province scales. The study area was the province of Siena, in central Italy. Following a DPSIR approach, the State indicators checked the Impact of agricultural policies (Drivers), which have increased the Pressure of specialized crops, and suggested Response actions. The indicators selected for the catchment scale stressed the consequences of land use change on soil quality, capability and suitability. They were: (1) land use and land cover; (2) soil and water conservation management system, (3) soil hydrological group, (4) land capability; (5) land suitability for wine grape production. At the province level, four original indicators highlighted at the reconnaissance scale the impact of the two crops on soil conservation and management – (6) soil erosion risk, (7) soil management – as well as on visual attractiveness of landscape – (8) slope length of vineyards, (9) crop saturation of the landscape unit and its variation in time. The results showed that, at the catchment level, the twenty-fold increase in specialized viticulture and olive tree cultivation, along with the generalised adoption of the “up and down slope” soil and water conservation system, caused the impairment of soil hydrological group, land capability and suitability for growing quality wine. At the province level, soil erosion risk and soil management difficulty almost doubled in the transition from the traditional mixed to the new specialized tree cultivation. The areas traditionally producing wine protected by appellation of origin (DOCG) determined the distribution of land use and all the other impact indicators. Slope length of vineyards showed that the enlargement of the surface covered by vines preferentially affected lands close to already established DOCG farms. DOCG areas resulted somewhat saturated by vineyards, but not by olive tree groves. The response should foresee the following actions: (i) when planting new olive groves and vineyards, measures should be taken to avoid the complete removal of the subsurface soil B horizon; (ii) new plantations should maintain slope degree of less than 21% in any part of the field; (iii) the shape of new plantations should conform to slope morphology, thus avoiding the creation of long, wide and uniform slopes. The aim should be to limit the length of the fields to less than 150–300 m and to adopt or preserve the contour management systems.

This research considered the varieties 'Frantoio' and 'Moraiolo' growing in rainfed olive trees (Olea europaea) and took place in Tuscany, central Italy. Soil moisture was monitored during the very meteorologically contrasting years 2002 and 2003 in two nearby olive groves. The plots had the same morphological and climatic conditions, but different soil types. Monocultivar oil samples were analyzed to determine fatty acids, minor polar compounds, and tocopherols content and were submitted to organoleptic analysis by a panel of trained tasters. The results highlighted that soil water regimen affects some nutraceutical components and the sensory evaluation of olive oil. Cultivar also affected yield components, polyphenols, and tocopherols content, but less than soil water availability. The plants on the soil inducing a relatively more intense and longer water deficit during summer (a Skeleti Calcaric Regosol) had an early ripening and gave the best results in terms of phenolic compounds and, consequently, antioxidant properties of the olive oil. The sensorial properties of the oil obtained from both cultivars on the Regosol were superior in both years of the trial.