Effects of historical charcoal burning on soil landscapes in West Connecticut, USA
Soil Sciences
Final Report Abstract
So-called relict charcoal piles (RCHs) are small anthropogenic relief forms and distinctive legacies of charcoal burning that were an important element of forest use in Central Europe and North America for many centuries. The focus of this project is how and to what extent did the historic charcoal industry shape the distribution, development, and characteristics of present-day soils in Connecticut, USA? The results presented here are based on several field campaigns that took place, particularly in 2017 and 2018, and a variety of laboratory analyses and GIS evaluations were also conducted. In northwestern Connecticut, 154 soil profiles were established and sampled by manual digging at 52 selected RCH sites in Litchfield County, a center of historic New England mining industry. RCH landforms result in three distinct soils according to WRB: charcoal rich horizons (Auh horizons), mineral soil horizons dividing multiple Auh horizons horizontally (Cu horizons) and buried former topsoil’s (Ahb horizons) or buried mineral soil horizons (Bwb horizons). Sites on flat terrain (< 4° slope) have mostly one Auh horizon, while sites on steeper terrain (> 4° slope) have mostly two, sometimes up to three Auh horizons. The total volume of RCH sites on slopes is positively correlated with local slope gradient, i.e., charcoal-burning forms and soils are more extensive in more relief terrain. Compared to reference soils, RCH soils are enriched in total soil organic carbon and especially in pyrogenic carbon. Vertical gradients of organic carbon concentrations in Auh and Cu horizons suggest an enrichment of non-pyrogenic organic matter in the topsoil and a vertical translocation of highly aromatic carbon compounds into intermediate and buried soil horizons. Furthermore, Auh horizons have a lower bulk density, a higher crystallinity ratio (Fed/Fet) of pedogenic iron oxides and are enriched in exchangeable elements (Ca2+, Mg2+, Mn2+) as well as oxalate extractable manganese-oxides compared to reference soils. A deep-learning based automated mapping workflow called ARCHMAGE (Automated Relict Charcoal Hearth Mapping and Geospatial Exploration) was created to gain a continuous, state wide database of RCH sites locations and other relevant geospatial information. This database, in combination with calculation of site specifics RCH volumes and soil carbon stocks, showed that in regions with high RCH site densities, significant additions to local soil organic and especially pyrogenic carbon stocks are present. This effect is scale dependent, with a larger effect size on a county scale and below (≤ 1: 650,000).
Publications
-
Effects of historical charcoal burning on soil landscapes in West Connecticut - Quantifying pyrogenic and organic soil carbon content of Technosols by FTIR analysis. EGU General Assembly 2019.
Bonhage, A., Mykhailova, S., Hirsch, F., Schneider, A., Raab, T., Fischer, T., Raab, A., Donovan, S. & Ouimet, W.
-
Effects of Historical Charcoal Burning on Soil Landscapes in West Connecticut, USA. Soil Science Society of America, International Soils Meeting, Soils Across Latitudes, San Diego 2019
Bonhage, A., Hirsch, F., Schneider, A., Raab, T., Raab, A., Ouimet, W. & Drohan, P.
-
Characteristics of small anthropogenic landforms resulting from historical charcoal production in western Connecticut, USA. CATENA, 195, 104896.
Bonhage, Alexander; Hirsch, Florian; Raab, Thomas; Schneider, Anna; Raab, Alexandra & Ouimet, Will
-
Stratigraphy and shape of relict charcoal hearths in Connecticut, USA. Virtuelle Jahrestagung des Arbeitskreises für Geomorphologie.
Bonhage, A., Hirsch, F., Raab, T., Schneider, A., Raab, A. & Ouimet, W.
-
A modified Mask region‐based convolutional neural network approach for the automated detection of archaeological sites on high‐resolution light detection and ranging‐derived digital elevation models in the North German Lowland. Archaeological Prospection, 28(2), 177-186.
Bonhage, Alexander; Eltaher, Mahmoud; Raab, Thomas; Breuß, Michael; Raab, Alexandra & Schneider, Anna
-
Automated large‐scale mapping and analysis of relict charcoal hearths in Connecticut (USA) using a Deep Learning YOLOv4 framework. Archaeological Prospection, 30(3), 251-266.
der, Vaart Wouter Verschoof‐van; Bonhage, Alexander; Schneider, Anna; Ouimet, William & Raab, Thomas
-
Comparing prediction algorithms in FTIR-based chemometric analysis to predict soil variables within centuries-old charcoal rich Technosols. Copernicus GmbH.
Ramezany, Shaghayegh; Bonhage, Alexander & Raab, Thomas
-
Do small landforms have large effects? A review on the legacies of pre-industrial charcoal burning. Geomorphology, 413, 108332.
Raab, T.; Raab, A.; Bonhage, A.; Schneider, A.; Hirsch, F.; Birkhofer, K.; Drohan, P.; Wilmking, M.; Kreyling, J.; Malik, I.; Wistuba, M.; van der Maaten, E.; van der Maaten-Theunissen, M. & Urich, T.
-
Large scale survey of anthropogenic soil landscapes in New England, USA, using state-of-the-art machine learning techniques (Yolov4). Mid-European Geomorphology Meeting 2022
Bonhage, A., Verschoof-van der Vaart, W., Raab, T., Schneider, A., Raab, A., Ouimet, W. & Hirsch, F.
-
Pyrogenic carbon in temperate forests - long-lasting impact of historical charcoal production on soils and ecosystems. Copernicus GmbH.
Bonhage, Alexander; Raab, Thomas; Schneider, Anna; Raab, Alexandra; Ramezany, Shaghayegh & Ouimet, William
-
Vertical SOC distribution and aromatic carbon in centuries old charcoal‐rich Technosols. European Journal of Soil Science, 73(4).
Bonhage, Alexander; Raab, Thomas; Schneider, Anna; Fischer, Thomas; Ramezany, Shaghayegh; Ouimet, William; Raab, Alexandra & Hirsch, Florian
-
From site to state – Quantifying multi-scale legacy effects of historic landforms from charcoal production on soils in Connecticut, USA. CATENA, 232, 107426.
Bonhage, Alexander; Raab, Thomas; Schneider, Anna; Raab, Alexandra; Ouimet, William; Völkel, Jörg & Ramezany, Shaghayegh
