Atmospheric metal pollution records in the Kovarska Bog (Czech Republic) as an indicator of anthropogenic activities over the last three millennia
Abstract
Three peat cores were extracted from the Kovarska Bog in the central Ore Mountains to study anthropogenic pollution generated by mining and metallurgy. The core profiles were C-14 dated, and concentrations of selected elements were determined by ICP MS and HG-AAS.
Principal component analysis indicated that Pb, Cu, As and Ag may be useful elements for the reconstruction of historical atmospheric pollution. Total and anthropogenic accumulation rates (ARs) of Pb, Cu and As estimated for the last ca. 3500 years showed similar chronologies, and revealed twelve periods of elevated ARs of Pb, As and Cu related to possible mining and metallurgic activities.
In total, four periods of elevated ARs of Pb, Cu and As were detected during the Middle and Late Bronze Ages, including a distinct Late Bronze Age pollution event between 1030 BCE and 910 BCE. The Iron Age included three episodes of increased ARs of Pb and As; the first and the most distinctive episode, recorded between 730 and 440 BCE, was simultaneous with the Bylany culture during the Hallstatt Period.
The Roman Age was characterized by one pollution event, two events were detected in the Middle Ages, and the last two during the modern period. Enhanced element ARs in the late 12th and 15th centuries clearly documented the onset of two periods of intense mining in the Ore Mountains.
Metal ARs culminated in ca. 1600 CE, and subsequently decreased after the beginning of the Thirty Years'War. The last boom of mining between 1700 CE and 1830 CE represented the last period of important metallurgical operations.
Late Medieval and modern period metal ARs are in good agreement with written documents. Earlier pollution peaks suggest that local metal production could have a much longer tradition than commonly believed; however, archaeological or written evidence is scarce or lacking.