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| Titel |
The geofingerprint of Pyroclastic Rocks/Typic Herorthents/Piedirosso chain surveyed in the Roccamonfina terroir, northwest Campania region, Italy |
| VerfasserIn |
M. Mercurio, E. Grilli, V. Morra, T. Prohaska, A. Buondonno, A. Langella |
| Konferenz |
EGU General Assembly 2012
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 14 (2012) |
| Datensatznummer |
250069856
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| Zusammenfassung |
| KEYWORDS: geofingerprint, strontium isotope ratio, Campanian Ignimbrite, Typic
Xerorthents, Roccamonfina
Investigations were carried out to evaluate the geofingerprint of Piedirosso wine produced
in the volcanic areas of Campania region (Southern Italy). The research was focused on the
terroir located in the southern area of the Roccamonfina volcanic complex according to a
procedure developed by the Authors. The protocol accounts for a careful sampling of the
soil and the grapes (branches, leaves) within the vineyards of “Masseria Felicia”
farm, located in Carano di Sessa Aurunca (Caserta), followed by a Piedirosso wine
production (monocultivar) on a pilot plant scale (grape harvest 2009). Samples
were digested by using strong acids (HF, HClO4) and suitably selected digestion
programs. Only soil samples were analysed after treatments with NH4NO3 in order to
simulate the labile fraction of metals in soil useful to estimate the 87Sr/86Sr isotope
ratio.
ICP-MC-MS analyses allowed to determine the 87Sr/86Sr isotopic composition whereas
ICP-QMS were carried out to measure Li, Be, B, V, Cr, Mn, Co, Ni, Cu, Zn, Ga,
As, Se, Rb, Sr, Mo, Ag, Cd, Ba, Tl, Pb, Bi, U and Rare Earth Elements. Finally,
XRPD analyses provided qualitative and semi-quantitative evaluations of the mineral
phases occurring in soil samples. Suitable agronomic analyses allowed a careful soil
classification.
The soil profile exhibits an Ap1-Ap2-Ap3-C1-2C2-3C3-4C4 horizonation. The color
varies from dark brown in Ap horizons to light yellowish brown in C horizons.
Rock fragments distribution varies irregularly along soil profile. Texture is loam in all
horizons, except Ap1, C1 and 3C3 that show a sandy loam texture. Mottles are evident in
all horizons except in 3C3 with a contrasting colors as reddish yellow or strong
brown.
Redoximorphic features occur in poorly (C1) and very poorly (2C2, 4C4) drained
horizons as coatings of iron and manganese oxides. Their color ranges between
very dark gray and reddish brown. Water pH is neutral-subacid in the whole soil
profile. For all horizons the Cation Exchange Capacity and the content of allophanic
materials are very low. The profile is classified as Typic Xerorthents (USDA-NRCS,
2010). By Land Suitability analysis, soil belongs to S1 class highly suitable for
vineyards.
Although the site is located on the southern slope of the Roccamonfina volcanic complex,
mineralogical data along with the survey investigation account for a substrate constituted by
deposits of the Campania Ignimbrite eruption (39.000 ka). However, we cannot disregard the
hypothesis that autochthonous pyroclastic products could have affected the pedogenetic
process, as the sampled site is placed on the borders of a fluvial axis, thus allowing the
deposition during flood periods of oldest deposits pertaining to the Roccamonfica volcanic
activity (0.58-0.1 Ma).
As far as the ICP analysis are considered it should be remarked that trace elements do not
provide useful information as possible geotracers. In fact, as already discussed in previous
researches, the artificially induced processes, such as fractionation and/or enrichment of
specific elements, occurring during the growth of the grapes and the wine production
(pruning, fertilization, manuring, wine production and bottling) preclude that trace and
ultratrace element concentrations transfer to the final product (wine) information univocally
linked to the substrate.
The whole 87Sr/86Sr compositional range, here defined as the geofingerprint of the
investigated chain, is within 0.7076 and 0.7088 with the highest values showed by the wine.
By contrast, the lowest ratios were measured in the leaves (0.7076-0.7077). These data
compared with those of the pyroclastic products of Roccamonfina (typical range
0.7066-0.7099) and Campi Flegrei (0.7065-0.7086) enable to confirm that, also for the
investigated terroir, the 87Sr/86Sr isotope ratio can be positively considered as geotracer of
wines produced on volcanic areas. Since the isotopic range for both volcanic districts shows a
partial overlap it was not possible to associate the investigated chain to a precise
petrological context. Specific-site investigations could provide a solution to this
issue.
Finally, the present study is a further evidence that a multidisciplinary approach enables
to lay the foundations for the implementation of a powerful tool of geographic food farming
geotracer for typical products widespread in the Italian perithyrrhenic volcanic areas. |
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