@misc{HirschRaabOuimetetal., author = {Hirsch, Florian and Raab, Thomas and Ouimet, William and Dethier, David and Schneider, Anna and Raab, Alexandra}, title = {Soils on historic charcoal hearths - terminology and chemical properties}, series = {Soil Science Society of America Journal : SSSAJ}, volume = {81}, journal = {Soil Science Society of America Journal : SSSAJ}, number = {6}, issn = {1435-0661}, doi = {10.2136/sssaj2017.02.0067}, pages = {1427 -- 1435}, abstract = {Historic charcoal hearth remains provide a unique archive of the long term interaction between biochar, soil development and plant growth. Charcoal as raw material was crucial for production of iron in iron works and hence numerous charcoal hearths can be found in the forests near historic iron works in Europe as well as the Eastern United States. Charcoal hearths are round to elliptical forms often around 10 m in diameter, and consist of several decimeter thick layers that contain charcoal fragments, ash, and burnt soil. We studied the soil chemistry of 24 charcoal hearths and compared them to the surrounding 'natural' soils in the northern Appalachians of northwestern Connecticut. The thickness of the topsoils on the charcoal hearths and their carbon content are remarkably higher than in the surrounding topsoils. The presence of residual products from charcoal production classifies the soils as Anthropic Udorthents (US Soil Taxonomy) or Spolic Technosols (Humic) according to the World Reference Base for Soil Resources. The widespread occurrence of charcoal hearth remains and their high spatial density in different ecosystems underlines their importance for further pedological research.}, language = {en} } @misc{HirschSchneiderBauriegeletal., author = {Hirsch, Florian and Schneider, Anna and Bauriegel, Albrecht and Raab, Alexandra and Raab, Thomas}, title = {Formation, Classification, and Properties of Soils at Two Relict Charcoal Hearth Sites in Brandenburg, Germany}, series = {Frontiers in Environmental Science}, volume = {6}, journal = {Frontiers in Environmental Science}, issn = {2296-665X}, doi = {10.3389/fenvs.2018.00094}, pages = {1 -- 15}, abstract = {Historical charcoal production can have significant effects on soil properties. We studied soils at former charcoal production sites (relict charcoal hearths, RCHs) and compared these soils with undisturbed soil next to the charcoal hearths and four typical soils on similar parent material located at distances between 10 and 70 km from the RCHs. In a landscape typical of the northern German lowland, we found Podsolige Braunerde [WRB: Brunic Arenosols (Protospodic)] outside of the RCHs and soils with a clearly different stratigraphy within the RCHs. The main feature of the soils at both of the studied RCHs is a heterogeneous, charcoal-bearing deposit that is ~30 cm thick. No indications of translocation or mineral transformation processes, which form distinct soil horizons after the deposition of anthropogenic material on the RCHs, are present. Except for the differences in color and total carbon content, the soil chemistry of the RCHs hardly differs from that of the soil outside of the charcoal hearth sites. The soil colors and magnetic susceptibility values strongly suggest that the RCH substrates and the underlying topsoil were affected by thermally induced transformation of iron (hydr-)oxides. Although the charring procedure normally requires ~2 weeks, the heating effect only reaches to a maximum depth of 8 cm into the buried soil below the charcoal hearths. The presence of reddish soil and an abrupt increase in magnetic susceptibility in the upper 2 cm of the soil below the charcoal hearths indicate the heat-induced transformation of iron (hydr-)oxides into maghemite. Brighter soil color and an increase in soil organic matter (SOM) in the lower parts of the buried topsoil demonstrate the combustion of SOM up to 5 cm depth below the RCH. According to the German Guidelines for Soil Mapping, the soils in the RCHs are classified as Regosols above Braunerde [WRB: Spolic Technosols (Arenic)]. However, because the anthropogenic features of these soil sediments are disregarded in the German Guidelines for Soil Mapping, we suggest adapting the "M" horizon to permit a jM horizon. Thus, the soils in the RCHs could be classified as Kolluviale Braunerde.}, language = {en} } @misc{BonhageMykhailovaHirschetal., author = {Bonhage, Alexander and Mykhailova, Larysa and Hirsch, Florian and Schneider, Anna and Raab, Thomas and Raab, Alexandra and Ouimet, William}, title = {FTIR-based inquiry on carbon in forest soil substrate enriched by aged biochar, West Connecticut, USA}, series = {Jahrestagung der Bodenkundlichen Gesellschaft der Schweiz und der Deutschen Bodenkundlichen Gesellschaft, Abstract-Band 2019}, journal = {Jahrestagung der Bodenkundlichen Gesellschaft der Schweiz und der Deutschen Bodenkundlichen Gesellschaft, Abstract-Band 2019}, pages = {S. 198}, abstract = {Relict charcoal hearths (RCHs) are sites of former charcoal production that are an increasingly well documented anthropogenic feature in forests of the temperate climate zone. However, the type and extent of a possible legacy effect from RCHs on soil physical and chemical properties is still largely unknown. In the Litchfield Hills in west Connecticut, RCH sites are located mainly on slopes and therefore differ in their architecture from lowland sites found in Europe. One of the striking characteristics of a RCH site regardless of its architecture is the enrichment of the soil with charcoal in varying particle sizes. In this study, we use chemical digestion coupled with a PLSR-model to quantify organic carbon and pyrogenic carbon in RCH substrate by MIR-DRIFT measurements. Furthermore, we analyse the quality of carbon compounds by MIR-DRIFT measurements on multiple grain size fractions to assess the post-burn enrichment of soil organic matter. Preliminary results show a markedly increase in organic and pyrogenic carbon in RCH substrates in relation to the natural forest soil. Also, our first results suggest that the enrichment of organic carbon is favoured on RCHsites. However, the causality between the enrichment of soil organic matter and site features remains open. Experiments using chemical extraction techniques on our samples hint at an increase of labile organic compounds and/or microbial biomass. This legacy effect of RCHs is however evident and further studies need to focus on how to address them.}, language = {de} } @misc{SchneiderBonhageRaabetal., author = {Schneider, Anna and Bonhage, Alexander and Raab, Alexandra and Hirsch, Florian and Raab, Thomas}, title = {Large-scale mapping of anthropogenic relief features—legacies of past forest use in two historical charcoal production areas in Germany}, series = {Geoarchaeology}, volume = {35}, journal = {Geoarchaeology}, number = {4}, issn = {1520-6548}, doi = {10.1002/gea.21782}, pages = {545 -- 561}, language = {en} } @misc{BonhageHirschSchneideretal., author = {Bonhage, Alexander and Hirsch, Florian and Schneider, Anna and Raab, Thomas and Raab, Alexandra and Ouimet, William and Drohan, Patrick J.}, title = {Effects of Historical Charcoal Burning on Soil Landscapes in West Connecticut, USA}, series = {Soil Science Society of America, International Soils Meeting, Soils Across Latitudes, San Diego 2019}, journal = {Soil Science Society of America, International Soils Meeting, Soils Across Latitudes, San Diego 2019}, language = {en} } @misc{RaabRaabBonhageetal., author = {Raab, Thomas and Raab, Alexandra and Bonhage, Alexander and Schneider, Anna and Hirsch, Florian and Birkhofer, Klaus and Drohan, Patrick J. and Wilmking, Martin and Kreyling, J{\"u}rgen and Malik, Ireneusz and Wistuba, Małgorzata and Maaten, Ernst van der and Maaten-Theunissen, Marieke van der and Urich, Tim}, title = {Do small landforms have large effects? A review on the legacies of pre-industrial charcoal burning}, series = {Geomorphology}, volume = {413}, journal = {Geomorphology}, issn = {0169-555X}, doi = {10.1016/j.geomorph.2022.108332}, pages = {16}, abstract = {Relict charcoal hearths (RCHs) are small, anthropogenic landforms resulting from past charcoal burning and reaching significant land coverage in pre-industrial mining areas. We review three coupled legacies linked by RCH development: (i) a landscape-scale geomorphic effect, (ii) a unique soil fingerprint, and (iii) an evolving novel ecosystem. The history and technique of charcoal production are described to clarify legacy effects. Applying a recently presented morpho-genetic catalogue is useful for classified mapping of RCH findings. The RCH numbers and calculated RCH densities per study region vary greatly and impose uncertainties due to insufficient methods causing over- or underestimations. Areas with high RCH densities between 50 and 500 RCH/km2 seem reasonable. Machine learning-based remote sensing techniques are promising approaches with which to better assess the full scale of charcoal burning legacies. RCH soil properties feature dark charcoal-rich technogenic substrate layers classified as Auh horizons according to the World Reference Base with significantly increased C contents. These Auh horizons can also exhibit specific physical and chemical properties, such as relatively low bulk density, high porosity, high plant available water content, low thermal conductivity and differences in cation exchange capacity or nutrient status. However, relevant studies are rare, and thus, the effects may differ by study region. Regarding vegetation, there seem to be four main effects: changes in forest structure, species composition, recruitment pattern and productivity. The number of studies on this issue is, however, also very limited. Even fewer studies have examined the soil fauna in RCHs; thus, the reported effects cannot be used to draw general conclusions. Notably, RCH research has made considerable progress in the last five years, especially in the Light Detection and Ranging-based mapping of these small landforms and identification of RCH-specific soil properties, but ecological legacies are not well understood; thus, more interdisciplinary and integrative studies are needed.}, language = {en} } @inproceedings{RaabRaabSchneideretal., author = {Raab, Thomas and Raab, Alexandra and Schneider, Anna and Hirsch, Florian and Takla, Melanie and Nicolay, Alexander and Bonhage, Alexander and Bauriegel, Albrecht and R{\"o}sler, Horst}, title = {Landnutzungsgeschichte und historische Landschaftsentwicklung in der Niederlausitz - Neue Befunde und aktuelle Forschung}, series = {Jahrestagung Arbeitskreis Geoarch{\"a}ologie, T{\"u}bingen, 4. Mai bis 7. Mai 2016}, booktitle = {Jahrestagung Arbeitskreis Geoarch{\"a}ologie, T{\"u}bingen, 4. Mai bis 7. Mai 2016}, abstract = {Seit 2010 untersucht eine interdisziplin{\"a}re Forschergruppe der BTU, des BLDAM und des LBGR die Landnutzungsgeschichte sowie die nat{\"u}rliche und anthropogen induzierte Landschaftsentwicklung in der Niederlausitz, Brandenburg. Systematische arch{\"a}ologische Grabungen des BLDAM im Vorfeld der laufenden Tagebaue sind eine wichtige Grundlage f{\"u}r geopedologische Untersuchungen. Die Arbeiten hatten zun{\"a}chst ihren r{\"a}umlichen Schwerpunkt in den Braunkohletagebauen nord{\"o}stlich von Cottbus (Tgb. Cottbus Nord, Tgb. J{\"a}nschwalde) und wurden dann ausgedehnt auf weitere Forstfl{\"a}chen n{\"o}rdlich von Peitz. Wir geben einen {\"U}berblick {\"u}ber die wichtigsten Erkenntnisse der letzten Jahre, pr{\"a}sentieren aktuelle Ergebnisse und zeigen zuk{\"u}nftige Forschungsfelder auf. Im Tagebau J{\"a}nschwalde sind zwischenzeitlich mehr als 1000 Relikte von Holzkohlmeilern (HKM) als Zeugen einer intensiven historischen Holznutzung arch{\"a}ologisch dokumentiert. Mit Stand Januar 2016 liegen Dendroalter von 64 HKM vor. Die Alter schwanken zwischen dem ausgehenden 16. Jahrhundert und der Mitte des 19. Jahrhunderts, was in etwa dem Betriebszeitraum des H{\"u}ttenwerks in Peitz entspricht. Die Mehrzahl der Meiler datiert auf den Beginn des 18. Jahrhunderts. Weitere Hinterlassenschaften der historischen Landnutzung sind u.a. W{\"o}lb{\"a}cker und begrabene Ackerb{\"o}den. Fossile B{\"o}den und ehemalige Landoberfl{\"a}chen sind stellenweise mit {\"a}olischen Sedimenten {\"u}berdeckt. 14C- und OSL-Datierungen an diesen B{\"o}den und Sedimenten lassen auf eine Intensivierung der {\"a}olischen Aktivit{\"a}t zur slawischen Zeit und im Deutschen Mittelalter schließen. Einige Relikte von HKM sind mit Sand {\"u}berweht worden, und an einer Stelle konnte das Alter dieser {\"a}olischen Sedimentation mittels Dendrodatierung des begrabenen Meilers auf1850 oder j{\"u}nger bestimmt werden. Allerdings stellt dies die Ausnahme dar. Der weitaus gr{\"o}ßere Teil der HKM-Relikte liegt direkt an der Oberfl{\"a}che und ist nicht begraben, was auf eine sehr geringe Winderosion in der Neuzeit schließen l{\"a}sst. Seit 2015 konnte im Rahmen des DFG-Projekts „R{\"a}umliche und zeitliche Dimension der historischen K{\"o}hlerei im Tauerschen Forst (Niederlausitz, Brandenburg). Ein Beitrag zur Kulturlandschaftsentwicklung des Norddeutschen Tieflands" (Az RA 1129/3-1; RA 931/6-1) ein weiteres Gebiet mit hoher HKM-Dichte untersucht werden. Erste Auswertungen der LiDAR-Daten ergeben eine Anzahl von 4449 ehemaligen Meilerstandorten im Tauerschen Forst. 26 Meilerstellen sind beprobt, die Dendroalter hierzu sind in Bearbeitung. Ebenfalls in j{\"u}ngerer Zeit fanden Untersuchungen zur Verbreitung von HKM-Relikten f{\"u}r das gesamte Land Brandenburg statt. Mit Hilfe eines bin{\"a}ren Modells wurden Gebiete mit hoher Wahrscheinlichkeit von HKM-Standorten detektiert. Im Rahmen des im November 2016 beginnenden DFG-Projekts „Die historische K{\"o}hlerei in Brandenburg - Analyse der r{\"a}umlichen Dimension und der Effekte auf bodenhydraulische Eigenschaften" (SCHN 1349/1-1) sollen nun neben der Verbreitung der historischen K{\"o}hlerei auch bodenrelevante Auswirkungen beschrieben und bewertet werden.}, language = {de} } @inproceedings{RaabRaabSchneideretal., author = {Raab, Alexandra and Raab, Thomas and Schneider, Anna and Hirsch, Florian and Takla, Melanie and Nicolay, Alexander and Bonhage, Alexander and M{\"u}ller, Frank and Heußner, Karl-Uwe and R{\"o}sler, Horst}, title = {Reconstructing anthropogenic landscape transformation in the surroundings of the ironwork Peitz (SE Brandenburg, Germany) - 16th to mid-19th centuries}, series = {4th International Landscape Archaeology Conference, Uppsala, 22nd - 25th August 2016}, booktitle = {4th International Landscape Archaeology Conference, Uppsala, 22nd - 25th August 2016}, publisher = {Department of archaeology and ancient history, Uppsala university,}, address = {Uppsala}, pages = {S. 152}, abstract = {Various sources provide information about land use history and landscape transformation. For a variety of reasons, the quality of information differs and is often discontinuous or incomplete. In this interdisciplinary study we take advantage of comprehensive archaeological data gathered by large-scale excavations that were necessary because of opencast lignite mining in Lusatia, Brandenburg, Germany. By using a GIS we integrate these archaeological findings with results from archival and literature studies, from historical maps, from landforms and soils as well as from analyses of shaded-relief maps derived from up-to-date LiDAR data. The long-term aim is to develop a palaeoenvironmental model and thus to reconstruct landscape changes caused by human activities. The focus of the study is the Peitz ironwork in SE Brandenburg, which was a large consumer of commodities for about 300 years. During the time it operated, extensive transformations are supposed to have affected the landscape in the vicinity because of wood consumption and especially charcoal production. Digital datasets about forested areas for different timespans reconstructed from historical maps were made available. In combination with dendrochronological dating of charred trees, the spatiotemporal dimension of charcoal kilns was determined. Also, sites of former bog iron ore mining could be identified. Moreover, the different sources contain further information about other forms of land uses such as agriculture, pastoralism and even viticulture. In conclusion we can highlight that the mosaic of past land use systems is different from the modern structure but that major changes in the forests have been retained.}, language = {en} } @misc{BonhageHirschSchneideretal., author = {Bonhage, Alexander and Hirsch, Florian and Schneider, Anna and Raab, Alexandra and Raab, Thomas and Donovan, Sally}, title = {Long term anthropogenic enrichment of soil organic matter stocks in forest soils - detecting a legacy of historical charcoal production}, series = {Forest Ecology and Management}, volume = {459}, journal = {Forest Ecology and Management}, issn = {0378-1127}, doi = {10.1016/j.foreco.2019.117814}, pages = {11}, abstract = {Recent findings of several thousand relict charcoal hearths (RCHs) in the Tauer Forest (Brandenburg, Germany) raise questions about the legacy effects of historical charcoal production on soil properties. RCH sites are characterized by the admixture of charcoal fragments to the natural forest soil, constituting an anthropogenic addition of carbon. Dendrochronological dating of large charcoal pieces has identified RCH ages ranging from 1709 AD to 1823 AD for a subarea in the Tauer Forest, which allows for assessing century old effects of charcoal application on forest soils. We measured the geometry and soil organic matter (SOM) content of 20 RCH sites in a selected part of the forest. The results provide a basis for estimating RCH SOM stocks on a 40-ha forest plot with 120 RCH sites. We also assessed the accuracy of RCH mapping based on digital elevation models (DEMs) with results from a ground survey. Over 50 \% of sites were not detected by the DEM-based mapping. In the range of statistical uncertainties, RCHs add between 18 \% and 32 \% of SOM to the stock of the natural forest soil in the study area. This equals an additional 4.9 - 8.9 Mg of carbon per hectare of forest soil. These substantial amounts of SOM are so far not recognized by any survey or forest soil SOM inventories. Considering recent studies, which uncovered tens- and hundreds- of thousands of RCHs throughout Europe and the USA, we conclude that further knowledge of RCH SOM is important for quantifying anthropogenic SOM stocks on a global scale.}, language = {en} } @misc{RaabBonhageSchneideretal., author = {Raab, Alexandra and Bonhage, Alexander and Schneider, Anna and Raab, Thomas and R{\"o}sler, Horst and Heußner, Karl-Uwe and Hirsch, Florian}, title = {Spatial distribution of relict charcoal hearths in the former royal forest district Tauer (SE Brandenburg, Germany)}, series = {Quaternary International}, volume = {Vol. 511}, journal = {Quaternary International}, issn = {1040-6182}, doi = {10.1016/j.quaint.2017.07.022}, pages = {153 -- 165}, abstract = {Historical charcoal production has long been an unconsidered type of forest utilization in lowland areas. The archaeological discovery of a large charcoal burning area in the forefield of the active opencast lignite mine J€anschwalde in SE Brandenburg (North German Lowlands) has highlighted the need for multidisciplinary research in the study of the dimensions of historical charcoal burning. The charcoal produced in our study area, the former royal forest district Tauer, provided energy for the nearby Peitz ironworks during its operation from the mid-16th to the mid-19th century. Here, we aimed to record the amount, size and distribution of relict charcoal hearths (RCHs) to examine their context with respect to the ironworks and to better understand the potential impacts on late Quaternary landscape change. The applied methods combined archaeological research with shaded-relief mapping of RCHs. To evaluate the detection success of RCHs in the shaded-relief maps (SRMs), we compared the results with the results from specific archaeological surveys and conventional forest site mapping. Furthermore, we analyzed our dataset with descriptive, comparable and spatial statistics. Additionally, dendrochronological dating of charcoal fragments from selected RCHs was used to investigate the temporal relationships among the RCHs. Approximately 6000 circular RCHs were manually digitally identified in the SRMs of the 109-km2 evaluable area. However, ground truthing showed that the shaded-relief maps could not completely capture all RCHs in our study area due to local conditions. At the regional scale, two focus areas with high RCH site densities were found. Statistical analysis revealed that the diameters of the RCHs range widely from 4 to 30.5 m. Spatial statistics were applied to the RCH diameters to aggregate areas with larger or smaller RCHs. At the small scale, no systematic arrangement of RCHs was obvious in the SRMs. Dendrochronological dating of selected RCHs lying close together could not detect significant spatiotemporal relationships or patterns. The dating results also showed that some areas have been preferentially used for charcoal production for over 300 years. Due to the homogeneity of the physiogeographical location factors, we assume that these factors are not superficially responsible for site selection. Instead, economic location factors and contemporary regulations are more likely responsible for the distribution of RCHs.}, language = {en} }