129-44 The Impacts of Warfare on Landscape Disturbance: Establishing a Baseline from Early Modern Period Strata

Abstract:

Our understanding of human influence on soil erosion often centers on agricultural development and urbanization. However, the effect of warfare on soil erosion is underexplored, with potentially significant consequences for the environment and contemporary geopolitics. This project addresses that gap in knowledge by examining early modern period conflicts in western Germany and northeastern France. Understanding how factors such as deforestation and troop movement shaped erosion during pre-industrial warfare is critical in doing so. Data from early modern period conflicts create a baseline for war-induced environmental disturbance. This baseline can then be used as a comparison with modern wars, showcasing how environmental impacts scale with time and technological development. The study focuses on the Rhine River watershed, a region that experienced a centuries-long era of repeated conflicts. To explore warfare’s impact, alluvial and colluvial stratigraphy is studied along the banks of river catchments within this area. A chronostratigraphic framework is presented that includes four new high-precision luminescence ages ranging from 0.13–0.40 ka. Soil equilibrium analyses are applied to each study point, which associate a numeric value with the soil erosion and development at a given location. These analyses allow us to visualize and compare impacts between continuous conflict and inter-war periods. Additionally, paleohydraulic reconstruction is used to distinguish stream flow background erosion from conflict-induced disturbance. To complement these methods, dendrochronological analysis is used throughout the study region, indicating that impacts of conflict scale dramatically from the early modern period to the 20th century. Current results from the early modern period soils display increased erosion sporadically throughout the river basin, indicating non-uniform effects from warfare. On the contrary, samples from the 20th century show more concentrated impacts. These both correlate with war strategy during their specific time periods, adhering to expected environmental disturbance. 

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