Location: National Soil Dynamics Laboratory
Title: Development of a soil test for determining the impact of soil disturbance Authors
|Gebhart, D -|
Submitted to: International Soil Tillage Research Organization Proceedings
Publication Type: Proceedings
Publication Acceptance Date: September 24, 2012
Publication Date: September 24, 2012
Citation: Torbert III, H.A., Gebhart, D.L. 2012. Development of a soil test for determining the impact of soil disturbance. Proceedings of the 19th Triennial International Soil Tillage Research Organization, September 24-28, 2012, Montevideo, Uruguay. CDROM. Interpretive Summary: Military training is often assumed to negatively impact archaeological resources, but methodologies to estimate or infer damage to these resources are expensive and time consuming. Cultural resources managers require a technique allowing them to estimate past and current impacts of training on archaeological site condition and determine if the site is capable of supporting future training activities. The technical objectives of this research were (1) to demonstrate that naturally occurring and culturally induced stratigraphic differences in a suite of soil parameters, such as soil organic carbon and chemical elements, at the interface of near-surface soil horizons can be disrupted to varying degrees by military training and other (e.g., agricultural) human actions and (2) to use this predictable stratification as the basis for an innovative, low-cost, widely applicable, reliable method to identify the onset and quantify the extent of adverse impacts to archaeological deposits that are associated with military training. Results indicated that significant treatment group by depth interactions for carbon, pH, total phosphorus, and extractable calcium, magnesium, manganese, and nickel indicated divergence in distribution of soil variables with depth that could be attributed to physical disturbance (mixing, inversion, or burial). Top-to-total, total-to-soluble, and leachable-to-nonleachable ratios were only developed on small subsets of data from each installation as proof of concept exercises, but preliminary analyses indicate these types of derived ratios may be promising areas for continued research.
Technical Abstract: United States Federal law requires land-managing agencies like the US Army to identify and take into account the impacts of their undertakings on archaeological resources. Development of a method that uses changes in the stratification of horizon interfaces to identify the onset of adverse impacts to archaeological deposits was investigated. This method will allow Cultural resource managers to identify types and levels of military training that risk adverse impacts to intact archaeological deposits. A study was initiated at Fort Benning, GA, and Fort Riley, KS with treatments including (1) archaeological habitation/no-training, (2) archaeological habitation/training, (3) non-habitation/no-training, and (4) non-habitation/training. Soil core samples for each treatment group were taken for 0-10, 10-20, 20-30, 30-50 cm increments for chemical analysis. Several promising elements were identified that may be useful as indicators for determining potential damage to archaeological deposits resulting from ground disturbing activities such as mechanized maneuver training. Differences between disturbed and undisturbed treatment groups were often evident at depths of 20-40 cm, indicating substantial soil inversion, displacement, or mixing. Soil C concentrations were always negatively impacted in disturbed treatment group soils, indicating that C might also be a reliable indicator of disturbance, especially when used in a ratio with another element that accumulates in undisturbed surface soil horizons. Analyses of ratios, including the Top-to-Total (ratio of upper 10 cm to entire 50 cm profile), the Total-to-Soluble (ratio of total elemental to soluble elemental concentration), and the Leachable to Non-Leachable (ratio of leachable/mobile element to a non-leachable/immobile element) indicated promising results.