High-resolution chronologies of anthropogenic soil substrates based on portable luminescence reader data.

Anthropogenic soil erosion and plaggen agriculture have shaped European agricultural landscapes for millennia. The anthropogenic soil substrates from these practices, such as colluvium and plaggen layers, are valuable geoarchives for reconstructing phases and rates of human activity. However, reconstructions on the landscape scale are limited by the small number of high-resolution chronologies of these substrates. We demonstrate how high-resolution chronologies can be developed for a plaggen soil and a colluvium in western Germany, using a portable optically stimulated luminescence (pOSL) reader, combined with conventional OSL dating and Bayesian age depth modeling. While the centimetre-scale pOSL chronologies provide no significant new insights for the uniformly developed plaggen soil, they reveal dynamic deposition processes in the colluvium that conventional OSL dating missed. Deposition rates in the colluvium varied by orders of magnitude over the last 3500 years, from near-zero deposition during the Migration period to brief episodes or even single events with accelerated deposition during Roman times and Late Middle Ages. These easily obtainable pOSL measurements promise scaling from local to regional contexts, offering new opportunities to reconstruct not just high-resolution chronologies but also spatial patterns of human-induced landscape change - currently beyond the reach of conventional methods.