Disentangling dust and sand deposition using a peat record in CE Europe (northern Romania): A multiproxy approach

Abstract

Aeolian sediments play an important role in the global climatic system and occur in the atmosphere due to soil and bedrock erosion. Here, we applied three different methods: geochemical (XRF), manual and laser-based particle size analysis to an ombrotrophic peat profile in the Carpathian Mountains to determine changes in aeolian deposition and wind/storm activity over the last 7800 years. The results show the following changes in aeolian fluxes (dust and sand) over time: 7800–4150 cal. yr BP – generally low dust fluxes with a periodic intensification of sand fluxes; 4150–2300 cal. yr BP – intense deposition of both dust and sand; 2300–150 cal. yr BP – fluctuating dust and sand fluxes; the last 200 years – the highest amplitude of both sand and dust fluxes. This study found that patterns in aeolian fluxes were influenced by a combination of climate and human impact, but with anthropogenic drivers, such as disturbance by fire, becoming more important in recent times. We also found a good agreement with other studies of dust fluxes for the earlier part of this record, but an increasing divergence over the last 3500 years. In terms of a methodological approach, we suggest that the three approaches each have both advantages and disadvantages; though overall laser-based particle size dust and sand reconstruction appears to best capture the most complex changes in both aeolian deposition rates and sources.