@misc{SekhriRaabDrohan, author = {Sekhri, Simran and Raab, Thomas and Drohan, Patrick J.}, title = {A Model Approach Assessing The Soil Properties Of Raised Bed Landscapes}, series = {EGU General Assembly 2022, Vienna, Austria, 23-27 May 2022}, journal = {EGU General Assembly 2022, Vienna, Austria, 23-27 May 2022}, doi = {10.5194/egusphere-egu22-7137}, abstract = {Common anthropogenic surface features across Scotland and Ireland are raised beds, which are agronomic ridges and furrows created prior to the 20th century to improve agricultural yield. Creating a raised bed improves yield by providing to the root zone better soil drainage, suitable micro-climatic conditions, and enrichment of organic matter and nutrients. Raised beds are structurally identifiable and can be examined using remote sensing techniques such as LIDAR imagery or aerial photography to analyze different dimensions of raised bed units. We examined the geomorphic parameters (height, length, breadth, ridge shape, furrow depth, unit orientation and block size) of raised beds found in the Fancroft region of County Offlay, Ireland. We developed a model of raised bed structural components and the distribution and change in soil properties including soil drainage, texture, horizon differentiation, soil colour, nutrient distribution, organic matter movement and the carbon influx and outflow have been provided. Our study aims to elucidate the typical geomorphic properties of raised bed landscapes, their basic chemical and physical soil properties and the landform attributes that may influence soil properties. Overall, the conceptual basis of raised bed landscapes have been visualised and presented to formulate an ideal raised bed theoretical model. Such a comprehensive model can be further extended to learn more about ancient agricultural practices, heritage, a causal link between present day and historical farming practices.}, language = {en} } @misc{DrohanBayuzickGuarinetal., author = {Drohan, Patrick J. and Bayuzick, Samuel and Guarin, Daniel and Raab, Thomas and Bonhage, Alexander and Diefenbach, Duane and McDill, Marc}, title = {USA Appalachian relict charcoal hearths have complex landscape and pedologic patterns that are unique from surrounding forest ecosystems}, series = {EGU General Assembly 2022, Vienna, Austria, 23-27 May 2022}, journal = {EGU General Assembly 2022, Vienna, Austria, 23-27 May 2022}, doi = {10.5194/egusphere-egu22-10315}, abstract = {Understanding how present-day abrupt change may alter forest ecosystem services is becoming more important due to ever-growing anthropogenic stresses. Forest managers trying the adapt to anthropogenic stress can benefit from the study and quantification of past abrupt changes in forests, especially when the legacy of past disturbance is still evident. Across the United Kingdom, Europe, and recently the northeastern United States, the examination of historic forest change due to charcoal manufacturing for the firing of iron or lime furnaces is yielding new insights relative to landscape stability, anthropogenic vs natural soil genesis, and forest evolution. A landscape classification process was used in the Central Appalachians (Pennsylvania) to identify 6,758 RCHs near Greenwood Furnace (Greenwood Furnace State Park) and Pine Grove Furnace (Pine Grove Furnace State Park). Topographic wetness index (TWI), and SAGA wetness index (SWI) were created using ~1m LiDAR data for two study areas to quantify surface hydrology effects and were compared to field soil volumetric water content (VWC) measurements. Modeled TWI and SWI values were different for RCH areas when compared to surrounding non-hearth areas indicating that RCHs were acting as a moisture sink. We also found that RCH platforms have different TWI and SWI values than rim areas. Using field measured volumetric water content, we found that as distance from the center of the RCH increases, the drier the soil becomes. Geomorphic position did not affect wetness. Surface soil samples were collected at 51 RCHs in the Greenwood Furnace study area. Laboratory analyses revealed that RCH soils have higher C content than surrounding native soils. Furthermore, while the pH of RCH soils is like native soils, the acidity is greater in RCHs. RCH soils at Greenwood Furnace were found to have lower Mehlich 3 P concentrations and lower K potentially effecting plant growth. RCH soils were found to have higher Ca concentration when compared to native soils. To examine within RCH differences in soil chemistry and morphology more closely, 8 of the 51 RCHs were sampled intensely along a topographic gradient. Control pits were excavated directly upslope from the RCHs. The RCHs were sampled in 5 positions across the hearth from the upslope to down slope position (A upslope rim of the RCH; B halfway point between A and C; C RCH center; D halfway C and E; E downslope rim of the RCH). Soil profiles were described and sampled at each position. The soil samples were analyzed for trace and rare earth element content (Aqua Regia digestion), soil pH (water) and fertility (Mehlich 3 extraction). Results indicated that RCHs are potentially a unique location of refugia for forest flora and perhaps fauna due to the unique geochemistry with higher bases and C and some concentrated metals and a higher soil water content hypothesized to be due to an observed restrictive morphology. Future research should more closely investigate whether RCHs support unique species assemblages and how they may play a role in enhancing today's forest biodiversity.}, 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, MaƂgorzata 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} } @misc{BayuzickGuarinBonhageetal., author = {Bayuzick, Samuel and Guarin, Daniel and Bonhage, Alexander and Hirsch, Florian and Diefenbach, Duane and McDill, Marc and Raab, Thomas and Drohan, Patrick J.}, title = {Small anthropogenic landforms from past charcoal production control moisture dynamics and chemistry in northcentral Appalachian soils}, series = {Geomorphology}, volume = {415}, journal = {Geomorphology}, issn = {1872-695X}, doi = {10.1016/j.geomorph.2022.108379}, pages = {1 -- 11}, abstract = {Throughout the northeastern United States (U.S.) and Europe, relict charcoal hearths (RCHs) are regularly being discovered in proximity to furnaces once used for the extraction of metal from ore or quick-lime production; charcoal produced in hearths was used as a furnace fuel. Given previous research has shown that topographic and subsurface disturbance can be great when a hearth is constructed, we hypothesize that hearth construction alters surface hydrology and soil chemistry in environments in and near hearths. We used a landscape classification process to identify 6758 hearths near furnaces at Greenwood and Pine Grove Furnace State Park, central and southcentral Pennsylvania, U.S. Two types of digital elevation model wetness indexes were used to quantify surface hydrology effects in and around hearths. Modeled wetness conditions were compared to field soil volumetric water content in RCHs near Greenwood Furnace State Park. Modeled wetness indexes indicate that RCH interiors are significantly wetter than RCH rim areas; RCHs are acting as a landscape moisture sink. Results also indicate that RCHs on slopes result in downslope drier conditions below RCHs. Field measured volumetric water content indicates that as distance from the center of the hearth increases, soil moisture significantly decreases. Geomorphic position was found to not be related to RCH wetness. Soil from RCHs, compared to nearby native soils, has significantly higher total C, a lower Mehlich 3 extractable acidity, higher Ca and P. No trend was evident with RCH soil chemistry and geomorphic position. The high frequency of RCH occurrence, in proximity to the furnace's RCHs supported, suggests that RCHs today could locally be an important niche for understory flora and fauna. Further research could explore how RCHs might be affecting surrounding plant populations and how within RCH patterns, especially on hillslopes, might represent a distinctly different scale of physical and chemical variability.}, language = {en} }