Recent carbon sequestration dynamics in four temperate SE European peatlands using ²¹⁰Pb dating

The last two centuries' anthropogenically-accelerated climatic changes and elevated atmospheric levels of CO₂ are influencing the recent carbon sequestration dynamics of peatlands, resulting in high variations of growth rates, and a general ascending trend in apparent carbon accumulation rates. In the present work, ²¹⁰Pb high-resolution chronologies and ¹³⁷Cs alternative markers were employed to study the recent carbon-related peat properties and their evolution throughout the last two centuries in four Sphagnum-dominated bogs in SE Europe (Romania). The results revealed a recent apparent carbon accumulation rate ranging from 9.5 to 437.5 g C m^-2 yr^-1, with a mean value of 144 ± 90.1 g C m^-2 yr^-1, that yielded an average increase of 18.25% of the rate from 1950 to the present period, suggesting an enhanced contemporaneous C uptake and storage in the peatlands. The mean C storage per unit area was 17.6 ± 7.6 kg C m^-2. The periods of decreased peat growth rates were identified and attributed to significant drought events at the regional scale. The results found in the present study confirm the observations and trends remarked by other researchers in the literature, and further reinforce the relevance of studying recent carbon dynamics in peatland ecosystems. The obtained ²¹⁰Pb chronologies were validated by ¹³⁷Cs markers, highlighting the suitability of this technique for peat profile dating.