Palaeoenvironmental Framing of the O Areal Roman Saltworks and Related Anthropogenic Activities in North-western Iberia

The NW Iberian city of Vigo contains buried structures of a Roman salinae that follow the ancient coastline. To investigate its environmental legacy, we studied two pedo-sedimentary profiles at the O Areal saltworks to reconstruct human activities during and after the salinae use, as well as framing them within the last two millennia of climate variability. The bottom layer consists of organic-rich sands, with marine palynomorphs, confined within the saltworks' structures that operated during the Early Roman Empire, when the demand in fish-salted products increased and the salting industry fluorished on the Atlantic coast of Iberia. During the Late Roman Empire, salt production at the O Areal may have ended, coeval with the development of a marsh with hydro-hygrophyte vegetation and the salting industry demise. The Roman environment also experienced intense agropastoralism that triggered water eutrophication. After Roman times, a dune phase sealed the archaeologicl structures. The overall trend points to a shift from a marine to a terrestrial setting coeval to known periods of climate variability. Therefore, humans and climate impacted the coast during the last two millennia, including the very intense Roman-period saltworks, agriculture and livestock. Roman times climate would have also influenced the saltworks' establishment and abandonment.

Automated summary

The city of Vigo in northwest Iberia contains buried structures of a Roman saltworks that follow the ancient coastline. A study was conducted to investigate the environmental impact of these structures and understand human activities during and after their use, as well as their relationship with climate variability over the past two millennia. The study found that salt production at the O Areal saltworks may have ended during the Late Roman Empire, coinciding with the development of a marsh and the decline of the salting industry. The overall trend suggests a shift from a marine to a terrestrial environment, influenced by both human activities and climate change.