Tag Archives: Spain

Spain’s Lead-Lined Lakes

ja13-coverResearchers from the University of Granada collected mountain lake sediments from Laguna de Río Seco in southern Spain that had accumulated over 10,000 years, trapping deposits from the atmosphere. In these stacks of mud, they found fine layers of lead that reveal millennia of metalworking and migration, and may be the oldest evidence of air pollution in southern Europe. “[The mud] has been capturing the evolution of air pollution from the Neolithic to present times and giving us an idea of the activity of each of the populations that have passed through southern Iberia,” says team leader José Antonio Lozano, “such as the Phoenicians, Romans, Visigoths, Moors, and more.”

The team dates the first man-made uptick in pollution to between 3,900 and 3,500 years ago, which matches the appearance at nearby sites of coins, weapons, and decorations that, when made, left behind lead by-products. The lead records also attest to a quiet period, when mining moved elsewhere in Iberia, and to a spike corresponding with a period of Roman mining. But all those signals are dwarfed by a more modern surge, which the team attributes to the leaded gasoline in heavy use from the 1950s to the 1970s. The good news, the researchers report, is that present-day lead levels are already below those of the worst Roman deposits.

This From the Trenches item first appeared in the July/August 2013 issue of Archaeology Magazine: [html] [pdf]

Spain replants after centuries of deforestation

First broadcast and published by Deutsche Welle: [html] [mp3]

Around this time of year in the Sierra de Guadarrama, a snow-capped mountain range outside Madrid, the snow is starting to melt. Below the tree line, the melting water soaks the earth in dense stands of pine trees. Further down, holly, oak and ash trees line the banks of mountain streams, and goats graze between granite rock formations.

Continue reading Spain replants after centuries of deforestation

Cave detective hunts for clues to past sea level

A yellow splash of light from Bogdan Onac’s headlamp bounces around the dripping orange walls of a cave like a frenetic firefly. At the other end of the beam, the University of South Florida paleoclimatologist explains that the walls of this cave, on the Mediterranean island of Majorca, have collected a bathtub ring of minerals as brackish water washes in and out. “Majorca is like a Gruyère,” Onac says, its underlying limestone filled with holes just like the cheese. Continue reading Cave detective hunts for clues to past sea level