Paleoenvironment of the Tagus - Final Report for the AAA by Cristiana Ferreira

Abstract: In the last six months it was possible to develop and enable the Archaeobotanic Laboratory Unit in the Polytechnic Institute of Tomar and start to develop new studies of Palynology and anthracology, thanks to the support provided by the Archeological Association of the Algarve.
The activities focused mainly on the implementation of laboratory, while a working space, on the development of reference collections of pollen and wood, to support archaeobotanic studies that are being developed, organization and availability of library materials, construction of databases and preparation of article publications and communications and early new archeobotany studies in the Alto Ribatejo.

January: During January, the activities were related to the organization and implementation of the Archaeobotany Laboratory Unit, when lists of the materials required and the existing one were created. In parallel, we analysed the bibliography on archaeobotanic studies that took place in the Alto Ribatejo; we started the preparation of the article "Environmental changes and the spread of agro-pastoralism in Western Iberia. The Alto Ribatejo (Central Portugal)" for publication in international media for publication, along with elaboration of maps by means of Geographic Information Systems (GIS), with the location of archaeological sites under investigation in the Alto Ribatejo.
Also during this month the planning of the areas of the collection in the field, in order to develop reference collections of palynology and anthracology and the preparation of record files for the registration of collected species.
In the last two days of the month the seeds from the excavation from the archaeological site of the of Islamic Gardens of Portas do Sol (citadel of Santarém) were sorted, so that later they could be studied, because it is intended to extend even further the thematic of study covering the remaining disciplines that compose the Archaeobotanic science.

February:  The activities of the month of February have had an essentially practical basis, focusing on organizing and conducting field trips to collect pollen from flowers, which was accompanied by photographic records so that later, forms are included in the registration of each species within the database of the reference collection. It was done a little research on physical-chemical treatments of artificial ageing of fresh pollen.
The species collected in the field trips were subjected to photographic records of the fresh pollen, and later on we applied a physical-chemical treatment for artificial ageing of pollen, and pollen samples were photographed already with a fossilized look, as it appears in the contexts that we will study. Some time of that month was also devoted to the preparation of a project for the FCT.




Some species collected and microscope-camera set up for digital viewing and recording of the fresh pollen (see photographs below). At the very right: artificially fossilized pollen of Pinus pinaster.


       Pinus pinaster                  Veronica persica              Raphanus sp.                               Pinus pinaster
                                                                                                                                             artificially fossilized

March: During the month of March the work went on collecting pollen and subsequent laboratory work and the photographic records; we started to prepare the database of palynology and anthracological with the software, that went through the outlining on the aspects that should be present in the database, so that it facilitates the acquisition of information of a given species, both in terms of morphology (pollen and wood) and physical characteristics, and in terms of ecological behaviour.

In the last two weeks of this month the classes of PhD in "Quaternário, Materiais e Cultura " which took place in Mação started, where, during two field trips, some more samples of fresh pollen were collected.
Given that, the time was filled by classes, and free time was devoted to the research in literature related to the evolution of vegetation since the last glacial and paleoclimatology and the preparation of a short presentation about the Archaeobotanic Laboratory presented in the Jornadas do Curso de Engenharias do Ambiente e Biológica “Ambiente e Bioenergias” held at the Polytechnic Institute of Tomar, on Friday the 25th.

April: During the first weeks of April, classes were followed on the PhD in “Quaternário, Materiais e Cultura”, held in Vila Real and Mação where the “XIV Seminário Internacional de Arte Pré-Histórica" was included.

The communication to be presented on the “5º Congresso do Neolítico Peninsular”, held in Lisbon during the day 7, 8 and 9 of April was concluded. This communication was named “As oscilações secas no período Atlântico e as suas implicações sócio-económicas. Um estudo comparativo em regiões de Portugal, Espanha e Brasil”. It was developed in collaboration with two research colleagues and presented orally on the last day.

Earlier this month, it took place at the Polytechnic Institute of Tomar the “Festa da Ciência, Cultura e Tecnologia”, held on the 6th and 7th, with which we have collaborated in developing some educational activities about archaeobotany and its utility for students of preparatory schools in the municipality of Tomar.
In the last weeks we proceeded to review the article for publication in the international journal, and the database anthracology and palynology (BD Pólen ID) was finalized, and is already in an active data entry phase, and we went back to the laboratory work of palynology, including photographic record and process physical-chemical samples. We have started to entry data in the BD Pollen ID database (picture right).

                                                                       

Some species that were collected during this           month.




 
                           Fresh pollen:                                                                                   Artificial pollen fossils:





                        
Quercus coccifera         Olea europaea var. silvestris                                 Corylus avellana          Quercus coccifera






    Laboratory work





May:  During the month of May we have developed various tasks related to the activity of the Archeobotanic Laboratory. Because the database BD Pólen ID is accessible to any student who wishes to query or data entry, we prepared a "Manual for Introduction of records and the use in general of the BD Pólen ID database."
We start to record the species present in the collection we already have, such as Pinus pinaster, Erica arborea, Arbutus unedo, Quercus robur, Quercus coccifera, etc.. Each record entered on the database is always accompanied by a thorough bibliographic search, that starts on the description from macro to micro to every species, through habitat type and geographic distribution.
During this month we started research work with collecting and processing anthracological samples of two archaeological sites in the Alto Ribatejo, where excavation campaigns were developed, and also collections of samples for paleopalynology were made. The first field trip for sampling to the archaeological site of the Povoado de Fontes took place, where Dr. Ana Rosa Cruz, the Centro de Pré-História of the IPT is in charge. It is a settlement with an Epipaleolithic datation, located in the municipality of Abrantes, where six burning structures were found. In the second field trip we visited the archaeological site of Barcelinhos cave, located in the municipality of Alvaiázere, and which is under the direction of Dr. Alexandra Figueiredo, where samples were again collected to highlight the archeobotanic potential for anthracology and palynology.



                                  Field work for anthracological sampling in Povoada de Fontes

During the last week of this month we started the lab work concerning the structures sampled in the Povoado de Fontes combustion sources. The sediment collected in the structures was subjected to flotation process in water, because the carbonized material is less dense than water and therefore floats, allowing further collection by settling in a column of sieves of different mesh sizes.

June:  During the month of June we continued to anthracological laboratory work on samples from the Povoado de Fontes, by means of the water flotation process. Given the obtained results of this first sampling at the end of this month or early next, we intend to schedule another field trip to the archaeological site to a more comprehensive collection of sediment burning structures. After the trial work on the fluctuation procedure and sorting process we start the identification of woody plant species from some charcoal




Charcoal from Povoado da Amoreira



In parallel to the work of identification of woody plant species from the charcoal, we continued with the introduction of
the species data of the reference collection in the database BD Pollen ID; we prepared a project for applications for PhD scholarships from the Fundação para a Ciência e Tecnologia (FCT). Also we prepared the article for the minutes of the 5º Congresso do Neolítico Peninsular which took place in April (see above). We started a new anthracological study in the archaeological site of the Povoado da Amoreira, by treating the sediments collected during the last campaign of excavations carried out in 2005.
Fig: Sorting samples from Povoado da Amoreira.

We finished the month of June with the preparation of the presentation "Late Pleistocene - Holocene in Alto Ribatejo (Western Iberia), deposits and paleoenvironment changes" to the XVIII INQUA - Congress, which will be held in July in Bern, Switzerland. The preparation of this communication was developed in collaboration with colleagues of the research department under the guidance of Professor Pierluigi Rosina.

Final Considerations

I want to thank the Archaeological Association of the Algarve for the support they gave us during these six months, enabling the creation of the Archeobotanic Laboratory and the continuation of studies of pre-history and paleoenvironmental reconstruction in the Alto Ribatejo, based on Palynology and Anthracology.
The implementation of this research area will allow the investigation of this region to increasingly achieve an interdisciplinary scope, contributing to a deeper understanding of the human societies of the past.
The Palaeoenvironmental studies that can be developed nowadays, taking into account the resources made these last months, not only constitute an addition to the information of the archaeological site, but became a fundamental tool for a most comprehensive knowledge of the relationships and interrelationships of the old societies and the environment, providing information on climate change that may have occurred, giving indications of colder or warmer, wet or dry times, and which species composed the plant communities. They offer a more "global" insight of the environment, and so becoming essential to an understanding of the dynamics that were involved in the transition to agro-pastoralism in the Alto Ribatejo.