Pre-industrial charcoal production in Lower Lusatia (Brandenburg, Germany): Detection and evaluation of a large charcoal-burning field by combining archaeological studies, GIS-based analyses of shaded-relief maps and dendrochronological age determination

In pre-industrial times, charcoal burning was a common source of energy across Europe. Charcoal production and its related consequences for the upland environment are well known due to historical and palaeoenvironmental research. In recent years, awareness has grown regarding the use of woods in the lowlands for charcoal production. In the last 20 years, a large charcoal-burning field in Lower Lusatia (Brandenburg, North German Lowlands) was discovered by systematic archaeological excavations of the opencast mine of Janschwalde. However, the excavations are limited to the mine, which only covers a portion of the Janschwalder Heide and the surrounding forests. In this paper, we present the results of our study regarding the spatial extension and timing of charcoal production in the Janschwalder Heide and its surrounding areas. We applied a combined approach using archaeological research results, GIS-analyses of shaded-relief maps (SRMs) and tree-ring dating of selected charcoal kiln remains. Approximately 900 excavated charcoal kiln ground plans were analysed, which provided a solid data basis for our GIS analyses. For an extensive evaluation, we enlarged our study area beyond the limits of the lignite mine. We identified and digitised the remains of the charcoal kilns by creating SRMs from digital elevation models (DEMs) that were based on high-resolution airborne laser scanning data (ALS). The data from the excavated and digitised charcoal kiln remains were analysed in terms of their sizes and spatial distributions. In addition, the dendrochronological ages of 16 selected charcoal kiln remains were determined. This study shows that charcoal production was more extensive than initially proven by archaeological excavations. The remains of more than 5000 charcoal kilns were detected on the SRMs across an area that was twice as large as the excavated charcoal-burning field. In the Janschwalder Heide, considerably more charcoal kiln relicts exist compared with the surrounding communal areas. Furthermore, the charcoal kiln remains in the Janschwalder Heide have larger diameters, suggesting large-scale charcoal production for supplying energy to the nearby ironworks at Peitz. However, the charcoal production on the communal land was most likely for local crafts. The ages of the charcoal kiln remains indicated that charcoal production occurred between the 17th and 19th centuries, corresponding with the main period of charcoal burning. Overall, our study suggested that charcoal production sites are underestimated in the modern landscapes of the North German Lowlands. (C) 2014 Elsevier Ltd and INQUA. All rights reserved.