The project has the ambitious aim of integrating classical archaeobotany with innovative analyses on strontium isotopic composition of plant remains to assess the provenance of plant materials. Another fundamental aspect of the research is the comprehension of the chemical composition of plant remains through a spectroscopic approach, in order to assess the processes that made fossilization of plant materials possible.
The case-study is provided by the plant materials from Alba Fucens (AQ, Abruzzi region). Alba Fucens, presumably founded by the Equi, an Italic tribe, became an important Roman colony at the end of the 4th century B.C. Inscriptions testify its prosperity during the Imperial period. Its splendor ceased in 537 A.D. during the Gothic war. The materials, deriving from years of excavations, are until now poorly investigated from a scientific perspective. Thanks to a scientific cooperation with the Abruzzo archaeological superintendence, the materials unearthed during years and years of excavations are now available and will be investigated scientifically. We will start with the content of a of a Roman cistern. Abruzzo is a nearly virgin land for this kind of study and the expectation to achieve important results is quite high. The expected results involve: 1) classical archaeobotany (which plants were used -for food, timber- or naturally present in the area); 2) analytical chemistry (which are the processes and the chemical compounds that made conservation of seeds and wood possible); geochemistry (were the plants locally grown or did they come from other areas?).
All the obtained data will obviously result in scientific articles that will partially fill the gap of archaeobotanical studies for the region. A final aim of the project is to disseminate the results with a threefold event, comprehending a scientific congress/workshop, a summer school for master and PhD students, and a divulgative seminar to outreach the local population.
The proposed research comprehends classical aspects and (almost) completely novel ones.
Classical aspects:
Identification of seeds and fruits from archaeological sites: this includes sampling, (on-site and in-lab) processing, hand-picking, observation of the remains using a stereomicroscope and identification using reference atlases. Wood remains can be identified through the observation of diagnostic sections (transversal, tangential and radial). A Nomarski microscope is necessary for the analysis of charred wood, while waterlogged samples can be analysed using a stereomicroscope.
Innovative aspects:
- Analytical chemical analyses can be very useful for the study of mineralization modalities of plant remains and the factors responsible for it. They can also be crucial for distinguishing between uncharred archaeobotanical remains and modern contaminants. However, they are rarely performed in association to archaeobotanical studies. We plan to perform qualitative chemical tests and spectroscopic techniques (SEM EDX, FTIR and Raman spectroscopy) to answer important research questions and develop protocols to share with the scientific community. In particular, after elemental characterization, which will provide a preliminary hypothesis on the mineralization composition, FTIR in different modes (specular reflectance and diffuse reflectance) will be used to precisely individuate the main mineral phases and to exclude modern contaminants. Finally, micro-Raman spectroscopy will be utilized to characterize minor species observable only on micrometer scale.
- The definition of the analytical protocol for the extraction and measurement of the stable strontium isotopes from fossil plant remains is essential for its systematic application to a wide range of archaeological contexts and archaeobotanical assemblages. Secondly, we plan to analyze the strontium isotope ratio from different wild plants in order to characterize the natural isotopic signatures and reconstruct the geographical origin of numerous plant remains. We also consider modern specimens of the same plant species as reference samples for the first systematic evaluation of possible variations in the strontium isotopic composition through time.
Progress beyond the State of the Art
The project is expected to be successful, as it has a high possibility of giving a boost to the development of the environmental research applied to cultural heritage. Abruzzo is an unexplored land from the point of view of the sciences applied to cultural heritage and a similar 360 degrees-wide project has never been carried out, not only in the region, but also on a national level.
In particular, this project is expected to:
1) provide information on spontaneous and cultivated plants present in the Alba Fucens area;
2) provide information on timber used on-site;
3) provide information on the state of conservation of plant materials by understanding the chemical mechanisms and processes that made it possible;
4) provide information on the area of provenance of plants through the use of strontium isotopes.
All these results will obviously result in scientific articles that will partially fill the gap of archaeobotanical studies already highlighted for the region.