I have just published a paper about the production and circulation of salt in the Neolithic/Chalcolithic Portugal. Is there anything in this issue that might be related to Portuguese ditched enclosures, namely those in inner Alenejo? I believe so.
The complex social dynamics that we can appreciate in the inner Alentejo region during the Late Neolithic and especially during the Chalcolithic, with an intensive consume of animals in large ditched enclosures and in others not so large, with the presence of some estuarine molluscs that might have been consumed, and intensive food processing and storage, would have generated a significant demand for salt.
That would reinforce a relation with coastal regions where some sites with evidences for salt production are known. But, as I stressed in the paper, these sites are all from Late Neolithic / Early Chalcolithic. So, where are the production sites from the middle / late 3rd millennium BC, the period when the Neo-Chalcolithic social dynamics in inner Alentejo were reaching their pick? I suggest that they may have been in the salt resources of central Iberia. The geological history of the Peninsula provided those interior areas with strong reservoirs of salt. The end of the sites that were producing salt in the Atlantic facade in the early chalcolithic, precisely when the most important area of demanding was developing, could represent a shift in the directions of interaction. The provenance studies show that Alentejo’s enclosures were involve in exchanges with coastal and more interior areas of the Peninsula. And those networks of interaction were dynamic and changes in predominant fluxes would be expectable.
The actual data on salt is suggestive. Concerning the salt, the inner Alentejo demand had two “coasts”: the Atlantic one and the central Iberian one. So, as the large ditched enclosure were involved in those large networks of relations, they might be decisive in the balance of those networks, stimulating some areas and depressing others through time.