A glimpse into the Hydroclimate and environmental trends of the past two millennia in Southern Transylvania, Romania

Abstract

Considering the importance of hydroclimate conditions in the development of both natural and anthropic environments, a better understanding of past conditions is imperative. Keeping this as a main trajectory, the objective of our study is the reconstruction of the past hydroclimate and environmental conditions in Central Romania over the last two millennia, by a high-resolution analysis of a peat sequence from Arpaşu de Sus (Făgăraș Depression, Southern Transylvania). We used biotic proxies (testate amoebae, pollen and spores) to quantitatively reconstruct the water level depth fluctuations in the peat bog and abiotic (lithology, AMS radiocarbon dating, organic matter content, bulk density, magnetic susceptibility) to reconstruct the vegetation dynamics and the human impact in the studied area. The peat bog had ombrotrophic characteristics throughout the studied period, with organic matter percentages ranging from 85 to 95%. The pollen analysis results show that the vegetation of this interval was characterized by extensive forests dominated by Fagus sylvatica, accompanied by Carpinus betulus and Alnus sp. The reconstructed water table depth values, based on testate amoeba assemblages, fluctuated between 32.9 and 11.8 cm. Our findings are in good agreement with other results from Romania and Central-Eastern Europe, bringing valuable insight to a better understanding of the hydroclimate changes that occurred in Europe in the last two millennia.